array:19 [
  "pii" => "X0211699500026104"
  "issn" => "02116995"
  "estado" => "S300"
  "fechaPublicacion" => "2000-06-01"
  "documento" => "article"
  "licencia" => "http://www.elsevier.com/open-access/userlicense/1.0/"
  "subdocumento" => "fla"
  "cita" => "Nefrologia. 2000;20 Supl 3:52-8"
  "abierto" => array:3 [
    "ES" => true
    "ES2" => true
    "LATM" => true
  ]
  "gratuito" => true
  "lecturas" => array:2 [
    "total" => 2751
    "formatos" => array:3 [
      "EPUB" => 160
      "HTML" => 2237
      "PDF" => 354
    ]
  ]
  "itemSiguiente" => array:15 [
    "pii" => "X021169950002609X"
    "issn" => "02116995"
    "estado" => "S300"
    "fechaPublicacion" => "2000-06-01"
    "documento" => "article"
    "licencia" => "http://www.elsevier.com/open-access/userlicense/1.0/"
    "subdocumento" => "fla"
    "cita" => "Nefrologia. 2000;20 Supl 3:59-67"
    "abierto" => array:3 [
      "ES" => true
      "ES2" => true
      "LATM" => true
    ]
    "gratuito" => true
    "lecturas" => array:2 [
      "total" => 4500
      "formatos" => array:3 [
        "EPUB" => 157
        "HTML" => 3731
        "PDF" => 612
      ]
    ]
    "es" => array:8 [
      "idiomaDefecto" => true
      "titulo" => "Inmunosupresión después de un trasplante renal"
      "tienePdf" => "es"
      "tieneTextoCompleto" => "es"
      "paginas" => array:1 [
        0 => array:2 [
          "paginaInicial" => "59"
          "paginaFinal" => "67"
        ]
      ]
      "contieneTextoCompleto" => array:1 [
        "es" => true
      ]
      "contienePdf" => array:1 [
        "es" => true
      ]
      "autores" => array:1 [
        0 => array:2 [
          "autoresLista" => "J. M. GRINYÓ , J. M. MORALES"
          "autores" => array:1 [
            0 => array:1 [
              "nombre" => "J. M. GRINYÓ , J. M. MORALES"
            ]
          ]
        ]
      ]
    ]
    "idiomaDefecto" => "es"
    "EPUB" => "https://multimedia.elsevier.es/PublicationsMultimediaV1/item/epub/X021169950002609X?idApp=UINPBA000064"
    "url" => "/02116995/00000020000000S3/v0_201502091332/X021169950002609X/v0_201502091332/es/main.assets"
  ]
  "itemAnterior" => array:15 [
    "pii" => "X0211699500026112"
    "issn" => "02116995"
    "estado" => "S300"
    "fechaPublicacion" => "2000-06-01"
    "documento" => "article"
    "licencia" => "http://www.elsevier.com/open-access/userlicense/1.0/"
    "subdocumento" => "fla"
    "cita" => "Nefrologia. 2000;20 Supl 3:41-51"
    "abierto" => array:3 [
      "ES" => true
      "ES2" => true
      "LATM" => true
    ]
    "gratuito" => true
    "lecturas" => array:2 [
      "total" => 2180
      "formatos" => array:3 [
        "EPUB" => 146
        "HTML" => 1683
        "PDF" => 351
      ]
    ]
    "es" => array:8 [
      "idiomaDefecto" => true
      "titulo" => "Dilemas del presente y perspectivas de futuro en el tratamiento de la osteodistrofia renal"
      "tienePdf" => "es"
      "tieneTextoCompleto" => "es"
      "paginas" => array:1 [
        0 => array:2 [
          "paginaInicial" => "41"
          "paginaFinal" => "51"
        ]
      ]
      "contieneTextoCompleto" => array:1 [
        "es" => true
      ]
      "contienePdf" => array:1 [
        "es" => true
      ]
      "autores" => array:1 [
        0 => array:2 [
          "autoresLista" => "E. FERNÁNDEZ GIRÁLDEZ"
          "autores" => array:1 [
            0 => array:1 [
              "nombre" => "E. FERNÁNDEZ GIRÁLDEZ"
            ]
          ]
        ]
      ]
    ]
    "idiomaDefecto" => "es"
    "EPUB" => "https://multimedia.elsevier.es/PublicationsMultimediaV1/item/epub/X0211699500026112?idApp=UINPBA000064"
    "url" => "/02116995/00000020000000S3/v0_201502091332/X0211699500026112/v0_201502091332/es/main.assets"
  ]
  "en" => array:8 [
    "idiomaDefecto" => true
    "titulo" => "Nutrition in chronic renal failure"
    "tieneTextoCompleto" => true
    "paginas" => array:1 [
      0 => array:2 [
        "paginaInicial" => "52"
        "paginaFinal" => "58"
      ]
    ]
    "autores" => array:1 [
      0 => array:2 [
        "autoresLista" => "J. BERGSTRÖM"
        "autores" => array:1 [
          0 => array:1 [
            "nombre" => "J. BERGSTRÖM"
          ]
        ]
      ]
    ]
    "textoCompleto" => "NEFROLOGÍA. Vol. XX. Suplemento 3. 2000 Nutrition in chronic renal failure J. Bergström Estocolmo. Suecia. BACKGROUND Malnutrition in patients with chronic renal failure is very common and is generally of mixed type with low body weight, loss of somatic protein (low muscle mass), low plasma levels of serum albumin and other visceral proteins as well as depletion of energy (adipose tissue) stores. In various studies, signs of malnutrition have been observed in 10-70% of HD patients and patients treated with continuous peritoneal dialysis (CAPD) 1. Several reports suggest that anthropometric and biochemical signs of malnutrition are risk factors for morbidity and mortality in HD and CAPD patients 2, 3. Malnutrition in patients with renal failure may have many causes, including disturbances in protein and energy metabolism, hormonal disturbances, as well as low food intake, caused by uremic toxicity, superimposed illness and psychosocial problems 4. Although some of the catabolic effects of chronic uremia may diminish or disappear after start of maintenance dialysis therapy, others may still persist. To these are added the catabolic effects of the dialytic treatment per se, which may increase protein requirements above those of non-dialyzed uremic patients and further aggravate malnutrition. Assessment of malnutrition History of malnutrition, weight loss and symptoms such as anorexia, nausea and vomiting are signs of impending or established malnutrition. It is useful to evaluate body mass status by calculating body mass index or relative body weight in % of standard body weight for equal sex and height (obtained from standard tables). Anthropometric measurements (skinfold thickness, arm muscle circumference, hand-grip strength) may give additional information about body composition. Subjective global nutritional assessment is a valuable tool for assessment of nutritional status which has been successfully applied in patients with end state renal disease (ESRD) 5, 6. Fluid status has to be taken into account, since CRF patients are frequently fluid overloaded. Newer and more sophisticated methods are bioelectrical impedance (total body water and fluid spa52 ces), dual emission X-ray absorptiometry (DEXA&#59; skeletal mineral mass and fat mass) whole body nitrogen by neutron activation analysis and nuclear magnetic resonance or computerized tomography (muscle surface area), the latter three methods are mainly research tools. Several plasma protein are considered to be nutritional markers for protein deficiency, e.g. albumin (most common), prealbumin and transferrin. However these proteins are also influenced by several non-nutritional factors 7. Nutritional intake can be estimated from dietary history and records. Intake of protein can be estimated from urea appearance rate measured directly in 24 urine and peritoneal dialysate 8, or, in hemodialysis (HD) patients, by urea kinetics, based on blood urea determinations 9. PROTEIN AND ENERGY REQUIREMENTS In normal adults, the average requirements for protein are about 0.6 g/kg of body weight/day, which after correction for 25% variability to include 97.5% of the population of young adults, raises the safe level of intake (daily allowance) to 0.75 g/kg/day 10. This variability is due to genetic differences, sex, age, physical activity, environment, chemical form of nutrients and effects of other dietary constituents. Studies in non-dialyzed patients with chronic renal failure indicate that 0.6 g/kg body weight of protein of high quality (a high content of essential amino acids) may sustain nitrogen balance. Diets with lower protein content (about 0.3 g/day) supplemented with essential amino acids or mixtures of essential amino acids and nitrogen-free ketoacid analogues have also been used successfully, especially in situations when dialysis resources are inadequate 11. The daily requirements of protein in dialysis patients are considerably higher than in normal individuals and non-dialyzed patients with chronic renal failure. On the basis of nitrogen balance studies and epidemiological studies, an intake of 1.2 g protein / kg body weight / day is generally recommended for HD and CAPD patients 1. Children have generally higher requirements of protein per kg body weight than adult patients 12. NUTRITION IN CHRONIC RENAL FAILURE Energy requirements depend on the level of physical activity, an intake of 35 to 40 kcal / kg of body weight/day being recommended for adult individuals not performing heavy physical exercise. There are data showing that during a given physical activity the energy expenditure of HD patients does not differ from that in normal subjects 13. Nor is there any evidence that the energy requirement in CAPD patients differ from normal. However, there are also conflicting data showing that resting energy expenditure is actually higher in HD patients than in normal controls 14. LOW NUTRITIONAL INTAKES AND ANOREXIA IN DIALYSIS PATIENTS Considering that requirements for protein are increased in dialysis patients and that an adequate energy supply is mandatory for maintaining the energy stores and optimizing the utilization of ingested protein, low protein and energy intakes must be especially harmful in such patients. Appetite suppression in CRF patients is multifactorial. Some factors that may contribute to a low intake of protein and energy are listed in table I. Uremic intoxication may lead to anorexia in nondialyzed patients resulting in spontaneous reduction in protein and energy intake, starting at a GFR of 25-30 ml/min with further reduction along with progression towards end-stage renal failure 15, 16. Uremic appetite suppression is also observed in underdialy- zed HD or CAPD patients. There is a decrease of protein and energy intake with time in CAPD patients 17, probably because they become underdialyzed as the total solute clearance falls, due to a decrease in residual renal function. The pathogenesis of uremic anorexia is not well understood, but several putatively anorexogenic factors have been identified in uremic plasma or in the central nervous system (table III). Low nutritional intakes may also be due to unpalatable or inadequate diets, medications, gastropathy and reduced intestinal motility, e.g., in diabetic patients with autonomic neuropathy. Congestive heart failure and inflammation-infection (sepsis in HD patients and peritonitis in PD patients), and other forms of co-morbidity are also associated with malnutrition, in which scenario proinflammatory cytokines appear to play a major role (vide infra). Psychosocial and socioeconomic factors, such as loneliness, depression, ignorance and poverty, especially in elderly patients and those with alcohol and drug problems may also be causes of low nutritional intakes. Nausea and vomiting during and immediately after HD, which are frequently associated with cardiovascular instability and post-dialysis fatigue, may lead to a reduction in food intake during the days on dialysis. In CAPD, the presence of dialysate in the peritoneal cavity may interfere with gastric emptying and intestinal motility and cause discomfort or pain, as may the peritoneal catheter. It is also possible that glucose or amino acids absorbed from the dialysis fluid may exert an inhibiting effect on food consumption as has been shown in experimental studies in rats. PROTEIN CATABOLIC FACTORS IN CHRONIC RENAL FAILURE Several factors in ESRD patients tend to decrease protein synthesis and/or increase protein breakdown, Tabla I. Causes of low nutritional intake in chronic renal failure Uremic toxicity (underdialysis) Unpalatable or inadequate diets Complicating illness Gastrointestinal illness Cardiovascular disease Inflammation, infection, sepsis Medications Psychosocial and socioeconomic factors Loneliness Depression Ignorance Poverty Poor dental status Alcohol and drug abuse Effects of hemodialysis Cardiovascular instability Nausea, vomiting Postdialysis fatigue Effects of peritoneal dialysis Abdominal distension and pain Dialytic uptake of glucose or amino acids Tabla II. Putative appetite-suppressing compounds in uremia Leptin Insulin Cholecystokinin Glucagon Serotonin Catecholamines Amino acid imbalances NO-synthase inhibitors Pro inflammatory cytokines (TNF, IL-1, IL-6) Middle molecules (plasma fraction with mol.weight 1 - 5 kd) 53 J. BERGSTRÖM resulting in muscle wasting (loss of somatic protein) and low plasma levels of albumin and other plasma proteins (visceral protein loss). However, hypoalbuminemia may have many causes, not directly related to malnutrition, such as inflammation-infection (albumin is a «negative» acute phase protein), dilution (fluid overload), increased capillary leakage, urinary and peritoneal albumin losses. Some of the most important factors leading to net protein catabolism in CRF are listed in table II. PHYSICAL INACTIVITY Many patients on renal replacement therapy are physically inactive for various reasons, such as fatigue, anemia, cardiac disease, skeletal-muscular disease, and psychological factors. Physical inactivity may result in muscle wasting and a negative nitrogen balance. The sedentary life-style may also contribute to resistance to insulin action. The insulin sensitivity may in fact be improved by exercise training. LOW ENERGY INTAKE AND PROTEIN CATABOLISM Metabolic studies in healthy individuals, nondialyzed CRF patients, HD patients and CAPD patients indicate that the nitrogen balance is highly dependent on the energy intake, so that a low energy intake results in negative nitrogen balance, whereas a high energy intake has a protein-saving effect 1. Ac- cordingly, a low energy intake, which is common in non-dialyzed and dialyzed patients with chronic renal failure, may impair the utilization of dietary protein, thus enhancing net catabolism of protein. METABOLIC ACIDOSIS It has become increasingly evident that metabolic acidosis is an important stimulus for protein breakdown in muscle 18. Acidosis elicits its catabolic effects in muscle by stimulating the ubiquitin-proteasome proteolytic pathway and enhancing branched-chain amino acid catabolism by increasing the expression of branchedchain ketoacid dehydrogenase. Moreover, acidosis attenuates the generation of serum albumin by the liver 19. In non-dialyzed chronic uremic patients, the correction of metabolic acidosis improves the nitrogen balance 20 and reduces urea appearance and muscle proteolysis 21. There are also some studies suggesting that correction of acidosis may correct amino acid abnormalities 22 and improve nutritional status in dialysis patients23. Considering that metabolic acidosis is the only «uremic toxin» known to enhance protein catabolism and that acidosis may also have other harmful effects, full correction should obviously be a goal of treatment. AMINO ACID ABNORMALITIES Patients with chronic renal failure exhibit several abnormalities in amino acid metabolism due to nutritional inadequacy, endocrine disturbances, toxic influences on amino acid metabolism, loss of metabolizing renal tissue, and reduced renal excretion. The plasma aminogram is abnormal, with low concentrations of most essential amino acids and high concentrations of some non-essential amino acids, and is in many respects similar to that observed in individuals suffering from protein malnutrition. Typical intracellular free amino acid abnormalities in skeletal muscle and erythrocytes are also observed in CRF patients. ENDOCRINE ABNORMALITIES Glucose intolerance, hyperinsulinemia, hyperglucagonemia, hyperparathyroidism and calcitriol deficiency are typically present in renal failure patients and have been suggested to enhance protein catabolism, although their roles in this respect are not well defined. In some cases with severe hyperparathyroidism the nutritional status may improve markedly after parathyroidectomy. Tabla III. Protein catabolic factors in chronic renal failure Physical inactivity Low energy intake Metabolic acidosis Amino acid abnormalities Endocrine abnormalities Glucose intolerance and insulin resistance, Hyperglucagonemia Growth hormone and IGF-1 resistance Hyperparathyroidism Renal anemia Corticosteroid therapy Co-morbidity Cardiac disease Inflammation, infection, sepsis Other Dialysis associated catabolism Amino acid losses (HD&#59; PD) Protein losses (PD) Low-grade inflammation (HD, PD?) 54 NUTRITION IN CHRONIC RENAL FAILURE Growth hormone and insulin-like growth factor-1 (IGF-1) resistance: Alterations in the growth hormone/IGF-1 axis have been described in renal failure, possibly as a consequence of uremia and associated malnutrition. The basal serum levels of growth hormone are elevated while there is an acquired resistance to growth hormone. Serum IGF-1 levels are normal or increased but its bioactivity seems to be impaired. Growth failure in children with chronic renal failure is multifactorial, but may to a large part be attributed to growth hormone/IGF-1 resistance, which may be overcome by treatment with pharmacological doses of human recombinant growth hormone. Anemia and erythropoietin: Renal anemia is usually present in most HD patients and may be severe, especially in anephric patients and in patients who are inadequately dialyzed. Anemia leads to fatigue, diminishing exercise capacity, and physical inactivity, which may contribute to muscle wasting and malnutrition. Correction of anemia with recombinant human erythropoietin (rHu-EPO) is reported to improve nutritional status to a moderate degree in groups of HD patients [24], which is presumably a secondary effect of anemia correction on general well-being, appetite and physical work capacity rather than a specific effect of rHu-EPO. Improvement of amino acid status has been observed in HD patients after correction of anemia with rH-EPO. Corticosteroids: CRF patients may require corticosteroid therapy for their primary disease or other diseases. They increase appetite but stimulate net protein catabolism, which may result in protein malnutrition. DIALYSIS PROCEDURES AS STIMULI OF NET PROTEIN CATABOLISM The fact that maintenance dialysis patients appear to have much higher requirement for protein than healthy individuals and non-dialyzed patients with chronic renal failure indicates that there are elements in the dialytic procedures which induce net protein catabolism. There is evidence that this is due to both reduced protein synthesis and incerased protein breakdown. Loss of amino acids and protein: During HD, the average loss of free amino acids in the dialysis fluid has been reported to be 5-8 g/dialysis, of which about one third are essential amino acids. Moreover, 4-5 g of peptide-bound amino acids are lost per dialysis. Thus, the total losses of amino acids are about 10-13 g/dialysis 1. Protein losses are insignifi- cant except after several reuses of dialyzers with high-flux polysulfone membranes, using bleach as disinfectant. The losses of free amino acids into the dialysate during CAPD are of the same magnitude (per week) or smaller than with HD. However, substantial loss of protein into the dialysate (20-100 g/weak) is a major drawback in peritoneal dialysis 1. Protein loss increases during and after peritonitis. Also, loss of protein is higher in high peritoneal transport rate patients. Biocompatibility: Blood-membrane contact elicits an inflammatory response, the intensity of which depends on the membrane material used, and which is more marked with cellulosic than with synthetic membranes. Inflammation induced by blood-membrane interaction may lead to muscle proteolysis 25, presumably mediated by monocyte activation with release of proinflammatory cytokines. CO-MORBIDITY AND MALNUTRITION Infection and inflammation Uremia leads to disturbances in the immune response, with cutaneous anergy and impaired granulocyte function, thus increasing the susceptibility to infection 26. A severe infection is an important stimulus for protein catabolism. HD patients are especially at risk for developing sepsis from infections in arteriovenous fistulas, grafts and in-dwelling venous catheters. In CAPD patients, peritonitis not only stimulates protein catabolism but also increases the loss of protein and other nutrients by dialysis. Chronic inflammation as in SLE, rheumatoid arthritis and other systemic diseases, also increases protein catabolism. In patients with renal transplant failure chronic inflammation and treatment with corticosteroids may act in concert to stimulate protein catabolism. Elevated plasma concentrations and increased generation by peripheral blood monocytic cells of proinflammatory cytokines (IL-1, IL-6, TNF-) are reported in non-dialyzed CRF patients and also in HD and CAPD patients without other signs of inflammation or infection 27, 28. High circulating IL-6 levels are associated with loss of body weight and reduced arm-muscle circumference 29 and TNF-levels are more elevated in anorectic peritoneal dialysis patients than in patients without anorexia 30. CARDIAC DISEASE AND MALNUTRITION Several studies demonstrate that patients with chronic cardiac failure without renal disease may de55 J. BERGSTRÖM velop weight loss, hypoalbuminemia and other signs of malnutrition, in its most advanced form (loss of < 10% of lean body mass) called cardiac cachexia 31. Inactivity, sympathetic overactivity and malabsorption are present in cardiac failure patients, and there is evidence that TNF- and other proinflammatory cytokines are major pathogenic factors in the development of malnutrition by enhancing protein catabolism and suppressing appetite. Infection and inflammation are also implicated as pathogenetic factors in atherosclerosis 32, conceivably mediated by proinflammatory cytokines. Cardiovascular disease and cardiac failure are frequently present in CRF patients and are the most common causes of death. Malnutrition, cardiac disease and inflammation (elevated C-reactive protein) are associated in CRF patients, and all three are strong predictors of mortality. INTERVENTIONS TO INCREASE FOOD INTAKE AND STIMULATE APPETITE Since uremia per se may cause anorexia, nausea and vomiting, a prerequisite for successful intervention is that uremic intoxication is alleviated or eliminated. In non-dialyzed patients this may be achieved by ordering a low protein diet. Such a diet should have a high energy content and may need to be supplemented with essential amino acids or their ketoanalogues to prevent protein malnutrition, and the nutritional status has to be monitored regularly to detect signs of malnutrition. Low protein diets are not recommended for patients with advanced renal failure without back up by dedicated dieticians and doctors&#59; instead, early start of dialysis is then recommended 33. Correction of underdialysis: In maintenance dialysis patients who are underdialyzed, the dose of dialysis should be increased so that it becomes adequate, since this may restore appetite and improve general well-being. If this is ignored, all other measures aimed at improving appetite may be futile. Co-morbidity factors, such as infection, cardiac failure and gastrointestinal dysfunction need to be identified and if possible remedied in order to ensure an adequate nutritional intake. Correction of anemia by treatment with recombinant human erythropoietin is also reported to improve appetite in dialysis patients 24. Dietary advice with the aim of increasing the quantity, quality and palatability of the food consumed may be helpful. Attention should be paid not only to the protein intake but also to the energy intake, which needs to be adequate for the optimal utilization of protein. Psychosocial and economical support should be provided whenever needed. 56 ENTERAL AND PARENTERAL NUTRITION If severe malnutrition develops despite adequate dialysis and measures to eliminate various anorectic and catabolic factors, enteral or parenteral nutritional supplementation may be necessary to ensure an adequate supply of nutrients. Feeding by a nasogastric tube, a percutaneous gastric catheter or a gastrostomy button is preferable, whenever possible, to parenteral feeding through an indwelling venous catheter, which is more expensive and carries the risk of catheter-related sepsis. The impact of such therapies on morbidity and mortality has not been assessed in adult patients. However, it has been applied successfully in infants and small children with CRF, in whom growth and weight gain has been reported 34. Intradialytic parenteral nutrition (IDPN) - i.e., the intravenous supply of a mixture of amino acids, glucose and lipids during the HD session - has become increasingly popular in recent years, since it can be given via the dialysis blood line while the patient is treated in the dialysis unit 35. Favorable effects on nutritional status, including anthropometric parameters and serum proteins, have been reported.in some studies, and also on morbidity and mortality in two not well controlled studies 36 Hence, the issue whether or not IDPN is of proven benefit is still controversial. Nevertheless, it is reasonable to try this form of therapy in severely malnourished HD patients when all other measures fail, and especially during episodes of concurrent illness, with deterioration of nutritional status. INTRAPERITONEAL AMINO ACIDS Since protein malnutrition is frequently present in CAPD patients, several investigators have examined the nutritional benefit of substituting amino acids for glucose as osmotic agent in peritoneal dialysis solutions, thereby increasing the net intake of protein precursors 37. In most of these studies such treatment was associated with improvement of nutritional indicators, including serum proteins, amino acid profiles, nitrogen balance and weight gain. Nutrineal® is a PD solution containing free amino acid in proportions adapted to the requirements of uremic patients, which is commercially available in several countries, has been shown to improve nitrogen balance in malnourished CAPD patients 38. Long term treatement with Nutrineal® has beneficial effects on nutritional status 39, 40. GROWTH FACTORS Recombinant human growth hormone (rHGH) is now available for the treatment of growth retarda- NUTRITION IN CHRONIC RENAL FAILURE tion and malnutrition&#59; its anabolic effects are mainly mediated through the induction of IGF-1. There is evidence that uremic patients are partly resistant to the metabolic effects of rhIGF 41. Treatment with rHGH is now an established therapy in growth-retarded uremic and transplanted children 12. Short-term studies in adult HD patients with malnutrition have demonstrated that the administration of rHGH in combination with parenteral nutrition results in reduced urea appearance, sustained nitrogen retention, and improvement of nutritional status 42. These results suggest that rHGH potentiates the anabolic effects of IDPN. The short term effects of rHGH has also been evaluated in a group of CAPD patients, in whom blood urea, urea appearance, serum potassium and serum phosphorus, decreased, suggesting protein anabolism 43. Recombinant human IGF-1 (rhIGF-1) has also been proposed as a nutritional support in malnourished dialysis patients and has been reported to cause anabolism in a small group of CAPD patients 41. Although data reported suggest that treatment with recombinant growth factors might be beneficial in adult malnourished patients with renal failure, it should be emphasized, that their long-term influence on mortality, morbidity and quality of life adult dialysis patients has not been established. REFERENCES 1. Bergström J, Lindholm B: Nutrition and adequacy of dialysis. How do hemodialysis and CAPD compare? Kidney Int 43 (Supl 40): S39-S50, 1993. 2. Bergström J: Nutrition and mortality in hemodialysis. J Am Soc Nephrol 6: 1329-1341, 1995. 3. Pollock CA, Ibels LS, Allen BJ, Ayass W, Caterson RJ, Waugh DA, Macadam C, Pennock Y, Mahony JF: Total body nitrogen as a prognostic marker in maintenance dialysis. J Am Soc Nephrol 6: 82-88, 1995. 4. Bergström J: Why are dialysis patients malnourished? Am J Kidney Dis 26: 229-241, 1995. 5. Cianciaruso B, Brunori G, Kopple JD, Traverso G, Panarello G, Enia G, Strippoli P, De Vecchi A, Querques M, Viglino G, y cols.: Cross-sectional comparison of malnutrition in continuous ambulatory peritoneal dialysis and hemodialysis patients. Am J Kidney Dis 26 (3): 475-486, 1995. 6. Qureshi AR, Anderstam B, Danielsson A, Divino-Filho JC, Gutiérrez A, Lindholm B, Bergström J: Factors predicting malnutrition in hemodialysis patients. Kidney Int 53: 773-782, 1998. 7. Heimbürger O, Bergström J, Lindholm B: Is serum albumin an indication of nutritional status in CAPD patients? Perit Dial Int 14: 108-114, 1994. 8. Bergström J, Heimbürger O, Lindholm B: Calculation of protein equivalent of total nitrogen appearance from urea appearance. Which formulas should be used? Perit Dial Int 18: 467-473, 1998. 9. Kopple JD, Jones MR, Eshaviah PR, Bergström J, Lindsay RM, Moran J, Nolph KD, Teehan BP: A proposed glossary for dialysis kinetics. Am J Kidney Dis 26: 963-981, 1995. 10. Young VR: Nutritional requirements in normal adults. In: Nutrition and the kidney, Mitch WE, Klahr S, eds. Boston: Little, Brown and Company, 1-34, 1993. 11. Walser M, Mitch WE, Maroni BJ, Kopple JD: Should protein intake be restricted in predialysis patients? Kidney Int 55(3): 771-777, 1999. 12. Kuizon BD, Salusky ID: Nutritional management of the child with renal insufficiency. In: Nutritional management of renal disease, Kopple JD, Massry S.G., ed. Baltimore: Williams Wilkins 687-711, 1997. 13. Monteon FJ, Laidlaw SA, Shaib JK, Kopple JD: Energy expenditure in patients with chronic renal failure. Kidney Int 30: 741-747, 1986. 14. Ikizler T, Wingard R, Sun M, Hakim R: Energy expenditure (EE) and respiratory quotient (RQ) during hemodialysis (HD) with different dialysis membrane (abstract). J Am Soc Nephrol 5: 493, 1994. 15. Kopple J, Chumlea W, Gassman J y cols.: Relationship between GFR and nutritional status. Results from the MDRD study. J Am Soc Nephrol 5: 325, 1994. 16. Ikizler T, Greene J, Wingard R, Parker R, Hakim R: Spontaneous dietary protein intake during progression of chronic renal failure. J Am Soc Nephrol 6: 1386-1391, 1995. 17. Lamaire NH, Vanholder R, Veyt, D., al. e: A longitudinal, five year survey of urea kinetic parameters in CAPD patients. Kidney Int 42: 426-432, 1992. 18. Mitch WB: Metabolic acidosis stimulates protein metabolism in uremia. Miner Electrolyte Metab 66: 62-65, 1996. 19. Ballmer PE, McNurlan MA, Hulter HN, Anderson SE, Garlick PJ, Krapf R: Chronic metabolic acidosis decreases albumin synthesis and induces negative nitrogen balance in humans. J Clin Invest 95(1): 39-45, 1995. 20. Papadoyannakis NJ, Stefanidis CJ, McGeown M: The effect of the correction of metabolic acidosis on nitrogen and potassium balance of patients with chronic renal failure. Am J Clin Nutr 40 (3): 623-627, 1984. 21. Stein A, Baker F, Larratt C, Bennett S, Harris K, Feehally J, Walls J: Correction of metabolic acidosis and the protein catabolic rate in PD patients. Perit Dial Int 14: 187-189, 1994. 22. Löfberg E, Wernerman J, Bergström J: Branched-chain amio acids in muscle increase during correction of acidosis in hemodialysis (HD) patients (Abstract). J Am Soc Nephrol 4, 1993. 23. Stein A, Moorhouse J, Iles-Smith H, Baker F, Johnstone J, James G, Troughton J, Bircher G, Walls J: Role of an improvement in acid-base status and nutrition in CAPD patients. Kidney Int 52 (4): 1089-1095, 1997. 24. Bárány P, Pettersson E, Ahlberg M, Hultman E, Bergström J: Nutritional assessement in anemic hemodialysis patients treated with recombinant human erythropietin. Clin Nephrol 35: 270-279, 1991. 25. Gutiérrez A, Bergström JA. A: Protein catabolism in sham-hemodialysis: the effect of different membranes. Clin Nephrol 38: 20-29, 1992. 26. Mattern WD, Hak LJ, Lamanna RW, Teasley KT, Laffell MS: Malnutrition, immune function, and the risk of infection in maintenance hemodialysis patients. Am J Kidney Dis 1: 206-218, 1982. 27. Pereira BJG, Shapiro L, King AV, Falagas ME, Strom JA, Dinarello CA: Plasma levels of IL-ß, TNF- and their specific inhibitors in undialyzed chronic renal failure, CAPD and hemodialysis patients. Kidney Int 45: 890-896, 1994. 28. Kimmel PL, Phillips TM, Simmens SJ, Peterson RA, Weihs KL, Alleyne S, Cruz I, Yanovski JA, Veis JH: Immunological function and survival in hemodialysis patients. Kidney Int 54: 236244, 1998. 29. Kaizu Y, Kimura M, Yoneyama T, Miyaji M, Hibi I, Kumagai H: Interleukin-6 may mediate malnutrition in chronic hemodialysis patients. Am J Kidney Dis 31: 93-100, 1998. 57 J. BERGSTRÖM 30. Aguilera A, Codoceo R, Selgas R, Garcia P, Picornell M, Diaz C, Sánchez C, Bajo A: Anorexigen (TNF-, cholecystokinin) and orexigen (neuropeptide Y) plasma levels in peritoneal dialysis (PD) patients: their relationship with nutritional parameters. Nephrol Dial Transplant 13: 1476-1483, 1998. 31. Freeman LM, Roubenoff R: The nutrition implications of cardiac cachexia. Nutr Rew 52: 340-347, 1994. 32. Ridker PM, Cushman M, Stampfer MJ, Tracey RP, Henneken CH: Inflammation, aspirin, and the risk of cardiovascular disease in apparently healthy man. New Engl J Med 336: 973979, 1997. 33. Golper TA: The rationale for Healthy Start dialysis [editorial]. Blood Purif 17 (1): 1-9, 1999. 34. Brewer ED: Pediatric experience with intradialytic parenteral nutrition and supplemental tube feeding. Am J Kidney Dis 33 (1): 205-207, 1999. 35. Fouque DJ: An evidence-based evaluation of intradialytic parenteral nutrition. Am J Kidney Dis 33 (1): 186-192, 1999. 36. Chertow GM, Ling J, Lew NL, Lazarus JM, Lowrie EG: The association of intradialytic parenteral nutrition administration with survival in hemodialysis patients. Am J Kidney Dis 24 (6): 912-920, 1994. 37. Wolfson M, Jones M: Intraperitoneal nutrition. Am J Kidney Dis 33 (1): 203-204, 1999. 38. Kopple JD, Bernard D, Messana J, Swartz R, Bergström J, Lindholm B, Lim V, Brunori G, Leiserowitz M, Bier DM y cols.: 39. 40. 41. 42. 43. Treatment of malnourished CAPD patients with an amino acid based dialysate. Kidney Int 47 (4): 1148-1157, 1995. Faller B, Aparicio M, Faict D, De Vos C, De Precigout V, Larroumet N, Guiberteau R, Jones M, Peluso F: Clinical evaluation of an optimized 1.1% amino-acid solution for peritoneal dialysis. Nephrol, Dial Transplant 10 (8): 1432-1437, 1995. Jones M, Hamburger R, Charytan C, Sandroni S, Dernard D, Piraino B, Schreiber M, Gehr T, Fein P, Friedlander M, Burkart J, Ross D, Zimmerman S, Swartz R, Knight T, Kraus A, McDonald L, Hartnett M, Weaver M, Hagen T, Vonesh E, Algrim Boyle C, Piscopo D, Martis L, Moran J: Treatment of malnutrition in peritoneal dialysis (PD) patients with a 1.1% amino-acid (AA) dialysis solution (abstract). Perit Dial Int 15 (Supl 1): S42, 1995. Fouque D: Therapeutic use of growth factors in renal disease. In: Nutrition in renal disease, Kopple JD, Massry SG, eds. Baltimore: Williams Wilkins, 777-798, 1997. Ziegler TR, Lazarus JM, Young LS, Hakim R, Wilmore DW: Effects of recombinant human growth hormone in adults receiving maintenance hemodialysis. J Am Soc Nephrol 2: 1130-1135, 1991. Ikizler TA, Wingard RL, P.J. F, Schulman G, Parker RA, Hakim RM: Effects of recombinant human growth hormone on plasma and dialysate amino acid profiles in CAPD patients. Kidney Int 50: 229-234, 1996. 58 "
    "pdfFichero" => "P7-E174-S140-A1386.pdf"
    "tienePdf" => true
  ]
  "idiomaDefecto" => "en"
  "url" => "/02116995/00000020000000S3/v0_201502091332/X0211699500026104/v0_201502091332/en/main.assets"
  "Apartado" => array:4 [
    "identificador" => "35407"
    "tipo" => "SECCION"
    "es" => array:2 [
      "titulo" => "Suplementos"
      "idiomaDefecto" => true
    ]
    "idiomaDefecto" => "es"
  ]
  "PDF" => "https://static.elsevier.es/multimedia/02116995/00000020000000S3/v0_201502091332/X0211699500026104/v0_201502091332/en/P7-E174-S140-A1386.pdf?idApp=UINPBA000064&text.app=https://revistanefrologia.com/"
  "EPUB" => "https://multimedia.elsevier.es/PublicationsMultimediaV1/item/epub/X0211699500026104?idApp=UINPBA000064"
]
Compartir
Información de la revista

Estadísticas

Siga este enlace para acceder al texto completo del artículo

Nutrition in chronic renal failure
J. BERGSTRÖM
Leído
6129
Veces
se ha leído el artículo
1757
Total PDF
4372
Total HTML
Compartir estadísticas
 array:19 [
  "pii" => "X0211699500026104"
  "issn" => "02116995"
  "estado" => "S300"
  "fechaPublicacion" => "2000-06-01"
  "documento" => "article"
  "licencia" => "http://www.elsevier.com/open-access/userlicense/1.0/"
  "subdocumento" => "fla"
  "cita" => "Nefrologia. 2000;20 Supl 3:52-8"
  "abierto" => array:3 [
    "ES" => true
    "ES2" => true
    "LATM" => true
  ]
  "gratuito" => true
  "lecturas" => array:2 [
    "total" => 2751
    "formatos" => array:3 [
      "EPUB" => 160
      "HTML" => 2237
      "PDF" => 354
    ]
  ]
  "itemSiguiente" => array:15 [
    "pii" => "X021169950002609X"
    "issn" => "02116995"
    "estado" => "S300"
    "fechaPublicacion" => "2000-06-01"
    "documento" => "article"
    "licencia" => "http://www.elsevier.com/open-access/userlicense/1.0/"
    "subdocumento" => "fla"
    "cita" => "Nefrologia. 2000;20 Supl 3:59-67"
    "abierto" => array:3 [
      "ES" => true
      "ES2" => true
      "LATM" => true
    ]
    "gratuito" => true
    "lecturas" => array:2 [
      "total" => 4500
      "formatos" => array:3 [
        "EPUB" => 157
        "HTML" => 3731
        "PDF" => 612
      ]
    ]
    "es" => array:8 [
      "idiomaDefecto" => true
      "titulo" => "Inmunosupresión después de un trasplante renal"
      "tienePdf" => "es"
      "tieneTextoCompleto" => "es"
      "paginas" => array:1 [
        0 => array:2 [
          "paginaInicial" => "59"
          "paginaFinal" => "67"
        ]
      ]
      "contieneTextoCompleto" => array:1 [
        "es" => true
      ]
      "contienePdf" => array:1 [
        "es" => true
      ]
      "autores" => array:1 [
        0 => array:2 [
          "autoresLista" => "J. M. GRINYÓ , J. M. MORALES"
          "autores" => array:1 [
            0 => array:1 [
              "nombre" => "J. M. GRINYÓ , J. M. MORALES"
            ]
          ]
        ]
      ]
    ]
    "idiomaDefecto" => "es"
    "EPUB" => "https://multimedia.elsevier.es/PublicationsMultimediaV1/item/epub/X021169950002609X?idApp=UINPBA000064"
    "url" => "/02116995/00000020000000S3/v0_201502091332/X021169950002609X/v0_201502091332/es/main.assets"
  ]
  "itemAnterior" => array:15 [
    "pii" => "X0211699500026112"
    "issn" => "02116995"
    "estado" => "S300"
    "fechaPublicacion" => "2000-06-01"
    "documento" => "article"
    "licencia" => "http://www.elsevier.com/open-access/userlicense/1.0/"
    "subdocumento" => "fla"
    "cita" => "Nefrologia. 2000;20 Supl 3:41-51"
    "abierto" => array:3 [
      "ES" => true
      "ES2" => true
      "LATM" => true
    ]
    "gratuito" => true
    "lecturas" => array:2 [
      "total" => 2180
      "formatos" => array:3 [
        "EPUB" => 146
        "HTML" => 1683
        "PDF" => 351
      ]
    ]
    "es" => array:8 [
      "idiomaDefecto" => true
      "titulo" => "Dilemas del presente y perspectivas de futuro en el tratamiento de la osteodistrofia renal"
      "tienePdf" => "es"
      "tieneTextoCompleto" => "es"
      "paginas" => array:1 [
        0 => array:2 [
          "paginaInicial" => "41"
          "paginaFinal" => "51"
        ]
      ]
      "contieneTextoCompleto" => array:1 [
        "es" => true
      ]
      "contienePdf" => array:1 [
        "es" => true
      ]
      "autores" => array:1 [
        0 => array:2 [
          "autoresLista" => "E. FERNÁNDEZ GIRÁLDEZ"
          "autores" => array:1 [
            0 => array:1 [
              "nombre" => "E. FERNÁNDEZ GIRÁLDEZ"
            ]
          ]
        ]
      ]
    ]
    "idiomaDefecto" => "es"
    "EPUB" => "https://multimedia.elsevier.es/PublicationsMultimediaV1/item/epub/X0211699500026112?idApp=UINPBA000064"
    "url" => "/02116995/00000020000000S3/v0_201502091332/X0211699500026112/v0_201502091332/es/main.assets"
  ]
  "en" => array:8 [
    "idiomaDefecto" => true
    "titulo" => "Nutrition in chronic renal failure"
    "tieneTextoCompleto" => true
    "paginas" => array:1 [
      0 => array:2 [
        "paginaInicial" => "52"
        "paginaFinal" => "58"
      ]
    ]
    "autores" => array:1 [
      0 => array:2 [
        "autoresLista" => "J. BERGSTRÖM"
        "autores" => array:1 [
          0 => array:1 [
            "nombre" => "J. BERGSTRÖM"
          ]
        ]
      ]
    ]
    "textoCompleto" => "NEFROLOGÍA. Vol. XX. Suplemento 3. 2000 Nutrition in chronic renal failure J. Bergström Estocolmo. Suecia. BACKGROUND Malnutrition in patients with chronic renal failure is very common and is generally of mixed type with low body weight, loss of somatic protein (low muscle mass), low plasma levels of serum albumin and other visceral proteins as well as depletion of energy (adipose tissue) stores. In various studies, signs of malnutrition have been observed in 10-70% of HD patients and patients treated with continuous peritoneal dialysis (CAPD) 1. Several reports suggest that anthropometric and biochemical signs of malnutrition are risk factors for morbidity and mortality in HD and CAPD patients 2, 3. Malnutrition in patients with renal failure may have many causes, including disturbances in protein and energy metabolism, hormonal disturbances, as well as low food intake, caused by uremic toxicity, superimposed illness and psychosocial problems 4. Although some of the catabolic effects of chronic uremia may diminish or disappear after start of maintenance dialysis therapy, others may still persist. To these are added the catabolic effects of the dialytic treatment per se, which may increase protein requirements above those of non-dialyzed uremic patients and further aggravate malnutrition. Assessment of malnutrition History of malnutrition, weight loss and symptoms such as anorexia, nausea and vomiting are signs of impending or established malnutrition. It is useful to evaluate body mass status by calculating body mass index or relative body weight in % of standard body weight for equal sex and height (obtained from standard tables). Anthropometric measurements (skinfold thickness, arm muscle circumference, hand-grip strength) may give additional information about body composition. Subjective global nutritional assessment is a valuable tool for assessment of nutritional status which has been successfully applied in patients with end state renal disease (ESRD) 5, 6. Fluid status has to be taken into account, since CRF patients are frequently fluid overloaded. Newer and more sophisticated methods are bioelectrical impedance (total body water and fluid spa52 ces), dual emission X-ray absorptiometry (DEXA&#59; skeletal mineral mass and fat mass) whole body nitrogen by neutron activation analysis and nuclear magnetic resonance or computerized tomography (muscle surface area), the latter three methods are mainly research tools. Several plasma protein are considered to be nutritional markers for protein deficiency, e.g. albumin (most common), prealbumin and transferrin. However these proteins are also influenced by several non-nutritional factors 7. Nutritional intake can be estimated from dietary history and records. Intake of protein can be estimated from urea appearance rate measured directly in 24 urine and peritoneal dialysate 8, or, in hemodialysis (HD) patients, by urea kinetics, based on blood urea determinations 9. PROTEIN AND ENERGY REQUIREMENTS In normal adults, the average requirements for protein are about 0.6 g/kg of body weight/day, which after correction for 25% variability to include 97.5% of the population of young adults, raises the safe level of intake (daily allowance) to 0.75 g/kg/day 10. This variability is due to genetic differences, sex, age, physical activity, environment, chemical form of nutrients and effects of other dietary constituents. Studies in non-dialyzed patients with chronic renal failure indicate that 0.6 g/kg body weight of protein of high quality (a high content of essential amino acids) may sustain nitrogen balance. Diets with lower protein content (about 0.3 g/day) supplemented with essential amino acids or mixtures of essential amino acids and nitrogen-free ketoacid analogues have also been used successfully, especially in situations when dialysis resources are inadequate 11. The daily requirements of protein in dialysis patients are considerably higher than in normal individuals and non-dialyzed patients with chronic renal failure. On the basis of nitrogen balance studies and epidemiological studies, an intake of 1.2 g protein / kg body weight / day is generally recommended for HD and CAPD patients 1. Children have generally higher requirements of protein per kg body weight than adult patients 12. NUTRITION IN CHRONIC RENAL FAILURE Energy requirements depend on the level of physical activity, an intake of 35 to 40 kcal / kg of body weight/day being recommended for adult individuals not performing heavy physical exercise. There are data showing that during a given physical activity the energy expenditure of HD patients does not differ from that in normal subjects 13. Nor is there any evidence that the energy requirement in CAPD patients differ from normal. However, there are also conflicting data showing that resting energy expenditure is actually higher in HD patients than in normal controls 14. LOW NUTRITIONAL INTAKES AND ANOREXIA IN DIALYSIS PATIENTS Considering that requirements for protein are increased in dialysis patients and that an adequate energy supply is mandatory for maintaining the energy stores and optimizing the utilization of ingested protein, low protein and energy intakes must be especially harmful in such patients. Appetite suppression in CRF patients is multifactorial. Some factors that may contribute to a low intake of protein and energy are listed in table I. Uremic intoxication may lead to anorexia in nondialyzed patients resulting in spontaneous reduction in protein and energy intake, starting at a GFR of 25-30 ml/min with further reduction along with progression towards end-stage renal failure 15, 16. Uremic appetite suppression is also observed in underdialy- zed HD or CAPD patients. There is a decrease of protein and energy intake with time in CAPD patients 17, probably because they become underdialyzed as the total solute clearance falls, due to a decrease in residual renal function. The pathogenesis of uremic anorexia is not well understood, but several putatively anorexogenic factors have been identified in uremic plasma or in the central nervous system (table III). Low nutritional intakes may also be due to unpalatable or inadequate diets, medications, gastropathy and reduced intestinal motility, e.g., in diabetic patients with autonomic neuropathy. Congestive heart failure and inflammation-infection (sepsis in HD patients and peritonitis in PD patients), and other forms of co-morbidity are also associated with malnutrition, in which scenario proinflammatory cytokines appear to play a major role (vide infra). Psychosocial and socioeconomic factors, such as loneliness, depression, ignorance and poverty, especially in elderly patients and those with alcohol and drug problems may also be causes of low nutritional intakes. Nausea and vomiting during and immediately after HD, which are frequently associated with cardiovascular instability and post-dialysis fatigue, may lead to a reduction in food intake during the days on dialysis. In CAPD, the presence of dialysate in the peritoneal cavity may interfere with gastric emptying and intestinal motility and cause discomfort or pain, as may the peritoneal catheter. It is also possible that glucose or amino acids absorbed from the dialysis fluid may exert an inhibiting effect on food consumption as has been shown in experimental studies in rats. PROTEIN CATABOLIC FACTORS IN CHRONIC RENAL FAILURE Several factors in ESRD patients tend to decrease protein synthesis and/or increase protein breakdown, Tabla I. Causes of low nutritional intake in chronic renal failure Uremic toxicity (underdialysis) Unpalatable or inadequate diets Complicating illness Gastrointestinal illness Cardiovascular disease Inflammation, infection, sepsis Medications Psychosocial and socioeconomic factors Loneliness Depression Ignorance Poverty Poor dental status Alcohol and drug abuse Effects of hemodialysis Cardiovascular instability Nausea, vomiting Postdialysis fatigue Effects of peritoneal dialysis Abdominal distension and pain Dialytic uptake of glucose or amino acids Tabla II. Putative appetite-suppressing compounds in uremia Leptin Insulin Cholecystokinin Glucagon Serotonin Catecholamines Amino acid imbalances NO-synthase inhibitors Pro inflammatory cytokines (TNF, IL-1, IL-6) Middle molecules (plasma fraction with mol.weight 1 - 5 kd) 53 J. BERGSTRÖM resulting in muscle wasting (loss of somatic protein) and low plasma levels of albumin and other plasma proteins (visceral protein loss). However, hypoalbuminemia may have many causes, not directly related to malnutrition, such as inflammation-infection (albumin is a «negative» acute phase protein), dilution (fluid overload), increased capillary leakage, urinary and peritoneal albumin losses. Some of the most important factors leading to net protein catabolism in CRF are listed in table II. PHYSICAL INACTIVITY Many patients on renal replacement therapy are physically inactive for various reasons, such as fatigue, anemia, cardiac disease, skeletal-muscular disease, and psychological factors. Physical inactivity may result in muscle wasting and a negative nitrogen balance. The sedentary life-style may also contribute to resistance to insulin action. The insulin sensitivity may in fact be improved by exercise training. LOW ENERGY INTAKE AND PROTEIN CATABOLISM Metabolic studies in healthy individuals, nondialyzed CRF patients, HD patients and CAPD patients indicate that the nitrogen balance is highly dependent on the energy intake, so that a low energy intake results in negative nitrogen balance, whereas a high energy intake has a protein-saving effect 1. Ac- cordingly, a low energy intake, which is common in non-dialyzed and dialyzed patients with chronic renal failure, may impair the utilization of dietary protein, thus enhancing net catabolism of protein. METABOLIC ACIDOSIS It has become increasingly evident that metabolic acidosis is an important stimulus for protein breakdown in muscle 18. Acidosis elicits its catabolic effects in muscle by stimulating the ubiquitin-proteasome proteolytic pathway and enhancing branched-chain amino acid catabolism by increasing the expression of branchedchain ketoacid dehydrogenase. Moreover, acidosis attenuates the generation of serum albumin by the liver 19. In non-dialyzed chronic uremic patients, the correction of metabolic acidosis improves the nitrogen balance 20 and reduces urea appearance and muscle proteolysis 21. There are also some studies suggesting that correction of acidosis may correct amino acid abnormalities 22 and improve nutritional status in dialysis patients23. Considering that metabolic acidosis is the only «uremic toxin» known to enhance protein catabolism and that acidosis may also have other harmful effects, full correction should obviously be a goal of treatment. AMINO ACID ABNORMALITIES Patients with chronic renal failure exhibit several abnormalities in amino acid metabolism due to nutritional inadequacy, endocrine disturbances, toxic influences on amino acid metabolism, loss of metabolizing renal tissue, and reduced renal excretion. The plasma aminogram is abnormal, with low concentrations of most essential amino acids and high concentrations of some non-essential amino acids, and is in many respects similar to that observed in individuals suffering from protein malnutrition. Typical intracellular free amino acid abnormalities in skeletal muscle and erythrocytes are also observed in CRF patients. ENDOCRINE ABNORMALITIES Glucose intolerance, hyperinsulinemia, hyperglucagonemia, hyperparathyroidism and calcitriol deficiency are typically present in renal failure patients and have been suggested to enhance protein catabolism, although their roles in this respect are not well defined. In some cases with severe hyperparathyroidism the nutritional status may improve markedly after parathyroidectomy. Tabla III. Protein catabolic factors in chronic renal failure Physical inactivity Low energy intake Metabolic acidosis Amino acid abnormalities Endocrine abnormalities Glucose intolerance and insulin resistance, Hyperglucagonemia Growth hormone and IGF-1 resistance Hyperparathyroidism Renal anemia Corticosteroid therapy Co-morbidity Cardiac disease Inflammation, infection, sepsis Other Dialysis associated catabolism Amino acid losses (HD&#59; PD) Protein losses (PD) Low-grade inflammation (HD, PD?) 54 NUTRITION IN CHRONIC RENAL FAILURE Growth hormone and insulin-like growth factor-1 (IGF-1) resistance: Alterations in the growth hormone/IGF-1 axis have been described in renal failure, possibly as a consequence of uremia and associated malnutrition. The basal serum levels of growth hormone are elevated while there is an acquired resistance to growth hormone. Serum IGF-1 levels are normal or increased but its bioactivity seems to be impaired. Growth failure in children with chronic renal failure is multifactorial, but may to a large part be attributed to growth hormone/IGF-1 resistance, which may be overcome by treatment with pharmacological doses of human recombinant growth hormone. Anemia and erythropoietin: Renal anemia is usually present in most HD patients and may be severe, especially in anephric patients and in patients who are inadequately dialyzed. Anemia leads to fatigue, diminishing exercise capacity, and physical inactivity, which may contribute to muscle wasting and malnutrition. Correction of anemia with recombinant human erythropoietin (rHu-EPO) is reported to improve nutritional status to a moderate degree in groups of HD patients [24], which is presumably a secondary effect of anemia correction on general well-being, appetite and physical work capacity rather than a specific effect of rHu-EPO. Improvement of amino acid status has been observed in HD patients after correction of anemia with rH-EPO. Corticosteroids: CRF patients may require corticosteroid therapy for their primary disease or other diseases. They increase appetite but stimulate net protein catabolism, which may result in protein malnutrition. DIALYSIS PROCEDURES AS STIMULI OF NET PROTEIN CATABOLISM The fact that maintenance dialysis patients appear to have much higher requirement for protein than healthy individuals and non-dialyzed patients with chronic renal failure indicates that there are elements in the dialytic procedures which induce net protein catabolism. There is evidence that this is due to both reduced protein synthesis and incerased protein breakdown. Loss of amino acids and protein: During HD, the average loss of free amino acids in the dialysis fluid has been reported to be 5-8 g/dialysis, of which about one third are essential amino acids. Moreover, 4-5 g of peptide-bound amino acids are lost per dialysis. Thus, the total losses of amino acids are about 10-13 g/dialysis 1. Protein losses are insignifi- cant except after several reuses of dialyzers with high-flux polysulfone membranes, using bleach as disinfectant. The losses of free amino acids into the dialysate during CAPD are of the same magnitude (per week) or smaller than with HD. However, substantial loss of protein into the dialysate (20-100 g/weak) is a major drawback in peritoneal dialysis 1. Protein loss increases during and after peritonitis. Also, loss of protein is higher in high peritoneal transport rate patients. Biocompatibility: Blood-membrane contact elicits an inflammatory response, the intensity of which depends on the membrane material used, and which is more marked with cellulosic than with synthetic membranes. Inflammation induced by blood-membrane interaction may lead to muscle proteolysis 25, presumably mediated by monocyte activation with release of proinflammatory cytokines. CO-MORBIDITY AND MALNUTRITION Infection and inflammation Uremia leads to disturbances in the immune response, with cutaneous anergy and impaired granulocyte function, thus increasing the susceptibility to infection 26. A severe infection is an important stimulus for protein catabolism. HD patients are especially at risk for developing sepsis from infections in arteriovenous fistulas, grafts and in-dwelling venous catheters. In CAPD patients, peritonitis not only stimulates protein catabolism but also increases the loss of protein and other nutrients by dialysis. Chronic inflammation as in SLE, rheumatoid arthritis and other systemic diseases, also increases protein catabolism. In patients with renal transplant failure chronic inflammation and treatment with corticosteroids may act in concert to stimulate protein catabolism. Elevated plasma concentrations and increased generation by peripheral blood monocytic cells of proinflammatory cytokines (IL-1, IL-6, TNF-) are reported in non-dialyzed CRF patients and also in HD and CAPD patients without other signs of inflammation or infection 27, 28. High circulating IL-6 levels are associated with loss of body weight and reduced arm-muscle circumference 29 and TNF-levels are more elevated in anorectic peritoneal dialysis patients than in patients without anorexia 30. CARDIAC DISEASE AND MALNUTRITION Several studies demonstrate that patients with chronic cardiac failure without renal disease may de55 J. BERGSTRÖM velop weight loss, hypoalbuminemia and other signs of malnutrition, in its most advanced form (loss of < 10% of lean body mass) called cardiac cachexia 31. Inactivity, sympathetic overactivity and malabsorption are present in cardiac failure patients, and there is evidence that TNF- and other proinflammatory cytokines are major pathogenic factors in the development of malnutrition by enhancing protein catabolism and suppressing appetite. Infection and inflammation are also implicated as pathogenetic factors in atherosclerosis 32, conceivably mediated by proinflammatory cytokines. Cardiovascular disease and cardiac failure are frequently present in CRF patients and are the most common causes of death. Malnutrition, cardiac disease and inflammation (elevated C-reactive protein) are associated in CRF patients, and all three are strong predictors of mortality. INTERVENTIONS TO INCREASE FOOD INTAKE AND STIMULATE APPETITE Since uremia per se may cause anorexia, nausea and vomiting, a prerequisite for successful intervention is that uremic intoxication is alleviated or eliminated. In non-dialyzed patients this may be achieved by ordering a low protein diet. Such a diet should have a high energy content and may need to be supplemented with essential amino acids or their ketoanalogues to prevent protein malnutrition, and the nutritional status has to be monitored regularly to detect signs of malnutrition. Low protein diets are not recommended for patients with advanced renal failure without back up by dedicated dieticians and doctors&#59; instead, early start of dialysis is then recommended 33. Correction of underdialysis: In maintenance dialysis patients who are underdialyzed, the dose of dialysis should be increased so that it becomes adequate, since this may restore appetite and improve general well-being. If this is ignored, all other measures aimed at improving appetite may be futile. Co-morbidity factors, such as infection, cardiac failure and gastrointestinal dysfunction need to be identified and if possible remedied in order to ensure an adequate nutritional intake. Correction of anemia by treatment with recombinant human erythropoietin is also reported to improve appetite in dialysis patients 24. Dietary advice with the aim of increasing the quantity, quality and palatability of the food consumed may be helpful. Attention should be paid not only to the protein intake but also to the energy intake, which needs to be adequate for the optimal utilization of protein. Psychosocial and economical support should be provided whenever needed. 56 ENTERAL AND PARENTERAL NUTRITION If severe malnutrition develops despite adequate dialysis and measures to eliminate various anorectic and catabolic factors, enteral or parenteral nutritional supplementation may be necessary to ensure an adequate supply of nutrients. Feeding by a nasogastric tube, a percutaneous gastric catheter or a gastrostomy button is preferable, whenever possible, to parenteral feeding through an indwelling venous catheter, which is more expensive and carries the risk of catheter-related sepsis. The impact of such therapies on morbidity and mortality has not been assessed in adult patients. However, it has been applied successfully in infants and small children with CRF, in whom growth and weight gain has been reported 34. Intradialytic parenteral nutrition (IDPN) - i.e., the intravenous supply of a mixture of amino acids, glucose and lipids during the HD session - has become increasingly popular in recent years, since it can be given via the dialysis blood line while the patient is treated in the dialysis unit 35. Favorable effects on nutritional status, including anthropometric parameters and serum proteins, have been reported.in some studies, and also on morbidity and mortality in two not well controlled studies 36 Hence, the issue whether or not IDPN is of proven benefit is still controversial. Nevertheless, it is reasonable to try this form of therapy in severely malnourished HD patients when all other measures fail, and especially during episodes of concurrent illness, with deterioration of nutritional status. INTRAPERITONEAL AMINO ACIDS Since protein malnutrition is frequently present in CAPD patients, several investigators have examined the nutritional benefit of substituting amino acids for glucose as osmotic agent in peritoneal dialysis solutions, thereby increasing the net intake of protein precursors 37. In most of these studies such treatment was associated with improvement of nutritional indicators, including serum proteins, amino acid profiles, nitrogen balance and weight gain. Nutrineal® is a PD solution containing free amino acid in proportions adapted to the requirements of uremic patients, which is commercially available in several countries, has been shown to improve nitrogen balance in malnourished CAPD patients 38. Long term treatement with Nutrineal® has beneficial effects on nutritional status 39, 40. GROWTH FACTORS Recombinant human growth hormone (rHGH) is now available for the treatment of growth retarda- NUTRITION IN CHRONIC RENAL FAILURE tion and malnutrition&#59; its anabolic effects are mainly mediated through the induction of IGF-1. There is evidence that uremic patients are partly resistant to the metabolic effects of rhIGF 41. Treatment with rHGH is now an established therapy in growth-retarded uremic and transplanted children 12. Short-term studies in adult HD patients with malnutrition have demonstrated that the administration of rHGH in combination with parenteral nutrition results in reduced urea appearance, sustained nitrogen retention, and improvement of nutritional status 42. These results suggest that rHGH potentiates the anabolic effects of IDPN. The short term effects of rHGH has also been evaluated in a group of CAPD patients, in whom blood urea, urea appearance, serum potassium and serum phosphorus, decreased, suggesting protein anabolism 43. Recombinant human IGF-1 (rhIGF-1) has also been proposed as a nutritional support in malnourished dialysis patients and has been reported to cause anabolism in a small group of CAPD patients 41. Although data reported suggest that treatment with recombinant growth factors might be beneficial in adult malnourished patients with renal failure, it should be emphasized, that their long-term influence on mortality, morbidity and quality of life adult dialysis patients has not been established. REFERENCES 1. Bergström J, Lindholm B: Nutrition and adequacy of dialysis. How do hemodialysis and CAPD compare? Kidney Int 43 (Supl 40): S39-S50, 1993. 2. Bergström J: Nutrition and mortality in hemodialysis. J Am Soc Nephrol 6: 1329-1341, 1995. 3. Pollock CA, Ibels LS, Allen BJ, Ayass W, Caterson RJ, Waugh DA, Macadam C, Pennock Y, Mahony JF: Total body nitrogen as a prognostic marker in maintenance dialysis. J Am Soc Nephrol 6: 82-88, 1995. 4. Bergström J: Why are dialysis patients malnourished? Am J Kidney Dis 26: 229-241, 1995. 5. Cianciaruso B, Brunori G, Kopple JD, Traverso G, Panarello G, Enia G, Strippoli P, De Vecchi A, Querques M, Viglino G, y cols.: Cross-sectional comparison of malnutrition in continuous ambulatory peritoneal dialysis and hemodialysis patients. Am J Kidney Dis 26 (3): 475-486, 1995. 6. Qureshi AR, Anderstam B, Danielsson A, Divino-Filho JC, Gutiérrez A, Lindholm B, Bergström J: Factors predicting malnutrition in hemodialysis patients. Kidney Int 53: 773-782, 1998. 7. Heimbürger O, Bergström J, Lindholm B: Is serum albumin an indication of nutritional status in CAPD patients? Perit Dial Int 14: 108-114, 1994. 8. Bergström J, Heimbürger O, Lindholm B: Calculation of protein equivalent of total nitrogen appearance from urea appearance. Which formulas should be used? Perit Dial Int 18: 467-473, 1998. 9. Kopple JD, Jones MR, Eshaviah PR, Bergström J, Lindsay RM, Moran J, Nolph KD, Teehan BP: A proposed glossary for dialysis kinetics. Am J Kidney Dis 26: 963-981, 1995. 10. Young VR: Nutritional requirements in normal adults. In: Nutrition and the kidney, Mitch WE, Klahr S, eds. Boston: Little, Brown and Company, 1-34, 1993. 11. Walser M, Mitch WE, Maroni BJ, Kopple JD: Should protein intake be restricted in predialysis patients? Kidney Int 55(3): 771-777, 1999. 12. Kuizon BD, Salusky ID: Nutritional management of the child with renal insufficiency. In: Nutritional management of renal disease, Kopple JD, Massry S.G., ed. Baltimore: Williams Wilkins 687-711, 1997. 13. Monteon FJ, Laidlaw SA, Shaib JK, Kopple JD: Energy expenditure in patients with chronic renal failure. Kidney Int 30: 741-747, 1986. 14. Ikizler T, Wingard R, Sun M, Hakim R: Energy expenditure (EE) and respiratory quotient (RQ) during hemodialysis (HD) with different dialysis membrane (abstract). J Am Soc Nephrol 5: 493, 1994. 15. Kopple J, Chumlea W, Gassman J y cols.: Relationship between GFR and nutritional status. Results from the MDRD study. J Am Soc Nephrol 5: 325, 1994. 16. Ikizler T, Greene J, Wingard R, Parker R, Hakim R: Spontaneous dietary protein intake during progression of chronic renal failure. J Am Soc Nephrol 6: 1386-1391, 1995. 17. Lamaire NH, Vanholder R, Veyt, D., al. e: A longitudinal, five year survey of urea kinetic parameters in CAPD patients. Kidney Int 42: 426-432, 1992. 18. Mitch WB: Metabolic acidosis stimulates protein metabolism in uremia. Miner Electrolyte Metab 66: 62-65, 1996. 19. Ballmer PE, McNurlan MA, Hulter HN, Anderson SE, Garlick PJ, Krapf R: Chronic metabolic acidosis decreases albumin synthesis and induces negative nitrogen balance in humans. J Clin Invest 95(1): 39-45, 1995. 20. Papadoyannakis NJ, Stefanidis CJ, McGeown M: The effect of the correction of metabolic acidosis on nitrogen and potassium balance of patients with chronic renal failure. Am J Clin Nutr 40 (3): 623-627, 1984. 21. Stein A, Baker F, Larratt C, Bennett S, Harris K, Feehally J, Walls J: Correction of metabolic acidosis and the protein catabolic rate in PD patients. Perit Dial Int 14: 187-189, 1994. 22. Löfberg E, Wernerman J, Bergström J: Branched-chain amio acids in muscle increase during correction of acidosis in hemodialysis (HD) patients (Abstract). J Am Soc Nephrol 4, 1993. 23. Stein A, Moorhouse J, Iles-Smith H, Baker F, Johnstone J, James G, Troughton J, Bircher G, Walls J: Role of an improvement in acid-base status and nutrition in CAPD patients. Kidney Int 52 (4): 1089-1095, 1997. 24. Bárány P, Pettersson E, Ahlberg M, Hultman E, Bergström J: Nutritional assessement in anemic hemodialysis patients treated with recombinant human erythropietin. Clin Nephrol 35: 270-279, 1991. 25. Gutiérrez A, Bergström JA. A: Protein catabolism in sham-hemodialysis: the effect of different membranes. Clin Nephrol 38: 20-29, 1992. 26. Mattern WD, Hak LJ, Lamanna RW, Teasley KT, Laffell MS: Malnutrition, immune function, and the risk of infection in maintenance hemodialysis patients. Am J Kidney Dis 1: 206-218, 1982. 27. Pereira BJG, Shapiro L, King AV, Falagas ME, Strom JA, Dinarello CA: Plasma levels of IL-ß, TNF- and their specific inhibitors in undialyzed chronic renal failure, CAPD and hemodialysis patients. Kidney Int 45: 890-896, 1994. 28. Kimmel PL, Phillips TM, Simmens SJ, Peterson RA, Weihs KL, Alleyne S, Cruz I, Yanovski JA, Veis JH: Immunological function and survival in hemodialysis patients. Kidney Int 54: 236244, 1998. 29. Kaizu Y, Kimura M, Yoneyama T, Miyaji M, Hibi I, Kumagai H: Interleukin-6 may mediate malnutrition in chronic hemodialysis patients. Am J Kidney Dis 31: 93-100, 1998. 57 J. BERGSTRÖM 30. Aguilera A, Codoceo R, Selgas R, Garcia P, Picornell M, Diaz C, Sánchez C, Bajo A: Anorexigen (TNF-, cholecystokinin) and orexigen (neuropeptide Y) plasma levels in peritoneal dialysis (PD) patients: their relationship with nutritional parameters. Nephrol Dial Transplant 13: 1476-1483, 1998. 31. Freeman LM, Roubenoff R: The nutrition implications of cardiac cachexia. Nutr Rew 52: 340-347, 1994. 32. Ridker PM, Cushman M, Stampfer MJ, Tracey RP, Henneken CH: Inflammation, aspirin, and the risk of cardiovascular disease in apparently healthy man. New Engl J Med 336: 973979, 1997. 33. Golper TA: The rationale for Healthy Start dialysis [editorial]. Blood Purif 17 (1): 1-9, 1999. 34. Brewer ED: Pediatric experience with intradialytic parenteral nutrition and supplemental tube feeding. Am J Kidney Dis 33 (1): 205-207, 1999. 35. Fouque DJ: An evidence-based evaluation of intradialytic parenteral nutrition. Am J Kidney Dis 33 (1): 186-192, 1999. 36. Chertow GM, Ling J, Lew NL, Lazarus JM, Lowrie EG: The association of intradialytic parenteral nutrition administration with survival in hemodialysis patients. Am J Kidney Dis 24 (6): 912-920, 1994. 37. Wolfson M, Jones M: Intraperitoneal nutrition. Am J Kidney Dis 33 (1): 203-204, 1999. 38. Kopple JD, Bernard D, Messana J, Swartz R, Bergström J, Lindholm B, Lim V, Brunori G, Leiserowitz M, Bier DM y cols.: 39. 40. 41. 42. 43. Treatment of malnourished CAPD patients with an amino acid based dialysate. Kidney Int 47 (4): 1148-1157, 1995. Faller B, Aparicio M, Faict D, De Vos C, De Precigout V, Larroumet N, Guiberteau R, Jones M, Peluso F: Clinical evaluation of an optimized 1.1% amino-acid solution for peritoneal dialysis. Nephrol, Dial Transplant 10 (8): 1432-1437, 1995. Jones M, Hamburger R, Charytan C, Sandroni S, Dernard D, Piraino B, Schreiber M, Gehr T, Fein P, Friedlander M, Burkart J, Ross D, Zimmerman S, Swartz R, Knight T, Kraus A, McDonald L, Hartnett M, Weaver M, Hagen T, Vonesh E, Algrim Boyle C, Piscopo D, Martis L, Moran J: Treatment of malnutrition in peritoneal dialysis (PD) patients with a 1.1% amino-acid (AA) dialysis solution (abstract). Perit Dial Int 15 (Supl 1): S42, 1995. Fouque D: Therapeutic use of growth factors in renal disease. In: Nutrition in renal disease, Kopple JD, Massry SG, eds. Baltimore: Williams Wilkins, 777-798, 1997. Ziegler TR, Lazarus JM, Young LS, Hakim R, Wilmore DW: Effects of recombinant human growth hormone in adults receiving maintenance hemodialysis. J Am Soc Nephrol 2: 1130-1135, 1991. Ikizler TA, Wingard RL, P.J. F, Schulman G, Parker RA, Hakim RM: Effects of recombinant human growth hormone on plasma and dialysate amino acid profiles in CAPD patients. Kidney Int 50: 229-234, 1996. 58 "
    "pdfFichero" => "P7-E174-S140-A1386.pdf"
    "tienePdf" => true
  ]
  "idiomaDefecto" => "en"
  "url" => "/02116995/00000020000000S3/v0_201502091332/X0211699500026104/v0_201502091332/en/main.assets"
  "Apartado" => array:4 [
    "identificador" => "35407"
    "tipo" => "SECCION"
    "es" => array:2 [
      "titulo" => "Suplementos"
      "idiomaDefecto" => true
    ]
    "idiomaDefecto" => "es"
  ]
  "PDF" => "https://static.elsevier.es/multimedia/02116995/00000020000000S3/v0_201502091332/X0211699500026104/v0_201502091332/en/P7-E174-S140-A1386.pdf?idApp=UINPBA000064&text.app=https://revistanefrologia.com/"
  "EPUB" => "https://multimedia.elsevier.es/PublicationsMultimediaV1/item/epub/X0211699500026104?idApp=UINPBA000064"
]
Información del artículo
ISSN: 02116995
Idioma original: Inglés
Datos actualizados diariamente
año/Mes Html Pdf Total
2024 Noviembre 3 10 13
2024 Octubre 39 36 75
2024 Septiembre 49 19 68
2024 Agosto 55 47 102
2024 Julio 46 28 74
2024 Junio 37 24 61
2024 Mayo 50 28 78
2024 Abril 24 20 44
2024 Marzo 37 27 64
2024 Febrero 30 37 67
2024 Enero 33 19 52
2023 Diciembre 27 21 48
2023 Noviembre 31 26 57
2023 Octubre 35 37 72
2023 Septiembre 23 26 49
2023 Agosto 32 17 49
2023 Julio 27 26 53
2023 Junio 36 27 63
2023 Mayo 32 28 60
2023 Abril 19 18 37
2023 Marzo 27 22 49
2023 Febrero 17 19 36
2023 Enero 26 15 41
2022 Diciembre 26 24 50
2022 Noviembre 29 27 56
2022 Octubre 27 29 56
2022 Septiembre 24 23 47
2022 Agosto 37 43 80
2022 Julio 28 33 61
2022 Junio 26 26 52
2022 Mayo 23 30 53
2022 Abril 30 50 80
2022 Marzo 35 39 74
2022 Febrero 36 31 67
2022 Enero 26 27 53
2021 Diciembre 30 32 62
2021 Noviembre 52 35 87
2021 Octubre 51 39 90
2021 Septiembre 25 24 49
2021 Agosto 33 33 66
2021 Julio 37 33 70
2021 Junio 26 18 44
2021 Mayo 46 30 76
2021 Abril 78 26 104
2021 Marzo 59 18 77
2021 Febrero 78 29 107
2021 Enero 36 21 57
2020 Diciembre 48 8 56
2020 Noviembre 46 2 48
2020 Octubre 24 6 30
2020 Septiembre 26 17 43
2020 Agosto 36 5 41
2020 Julio 40 13 53
2020 Junio 60 7 67
2020 Mayo 51 14 65
2020 Abril 75 14 89
2020 Marzo 62 7 69
2020 Febrero 70 19 89
2020 Enero 69 21 90
2019 Diciembre 41 11 52
2019 Noviembre 54 14 68
2019 Octubre 55 13 68
2019 Septiembre 65 9 74
2019 Agosto 36 12 48
2019 Julio 38 11 49
2019 Junio 28 5 33
2019 Mayo 27 13 40
2019 Abril 76 19 95
2019 Marzo 31 8 39
2019 Febrero 36 11 47
2019 Enero 34 7 41
2018 Diciembre 39 24 63
2018 Noviembre 56 7 63
2018 Octubre 57 12 69
2018 Septiembre 52 6 58
2018 Agosto 26 9 35
2018 Julio 32 4 36
2018 Junio 23 4 27
2018 Mayo 44 11 55
2018 Abril 26 3 29
2018 Marzo 36 4 40
2018 Febrero 12 2 14
2018 Enero 21 2 23
2017 Diciembre 23 5 28
2017 Noviembre 30 4 34
2017 Octubre 31 5 36
2017 Septiembre 25 6 31
2017 Agosto 33 22 55
2017 Julio 31 8 39
2017 Junio 23 2 25
2017 Mayo 25 1 26
2017 Abril 20 7 27
2017 Marzo 14 21 35
2017 Febrero 8 1 9
2017 Enero 13 1 14
2016 Diciembre 30 7 37
2016 Noviembre 35 6 41
2016 Octubre 23 3 26
2016 Septiembre 47 1 48
2016 Agosto 77 3 80
2016 Julio 62 3 65
2016 Junio 58 0 58
2016 Mayo 95 0 95
2016 Abril 48 0 48
2016 Marzo 49 0 49
2016 Febrero 50 0 50
2016 Enero 30 0 30
2015 Diciembre 47 0 47
2015 Noviembre 46 0 46
2015 Octubre 40 0 40
2015 Septiembre 47 0 47
2015 Agosto 39 0 39
2015 Julio 38 0 38
2015 Junio 14 0 14
2015 Mayo 34 0 34
2015 Abril 2 0 2
Mostrar todo

Siga este enlace para acceder al texto completo del artículo

Idiomas
Nefrología
es en

¿Es usted profesional sanitario apto para prescribir o dispensar medicamentos?

Are you a health professional able to prescribe or dispense drugs?