To the editor: Penile necrosis is a rare entity and only a few cases have been described in patients on dialysis.1,2 In these patients it can be associated to diabetes mellitus (DM), cholesterol emboli and seldom to calciphylaxis.1,3,4 The diagnosis relies on clinical picture, history, physical exam and on other investigations like skin biopsy.1 We present a case of calciphylaxis in an infrequent location in a patient on hemodialysis.
A 43 year-old male was on periodic hemodialysis because of chronic glomerulonephritis. In the next three years the Ca/P product was persistently higher than 70 mg2/dL2, he had hyperphosphatemia and severe hyperparathyroidism (iPTH 1200 pg/mL). No control could be achieved either with calcitriol or with subtotal parathyroidectomy, which was performed in January of 2005. Since the intervention the PTH level was 200 pg/mL, and calcium and phosphorus levels were 8.5 mg/dL and 4 mg/dL, respectively. In September of 2005 he was admitted because of general deterioration and progressive appearance of petechiae on the penis, which evolved to necrosis (fig. 1).
Laboratory findings were the following: 9,100 leucocytes/mm3, Hb 9.8 g/dL, proteins 4.4 g/dL, P 4.32 mg/dL, and PTH 248 pg/mL. Coagulation parameters were normal and HIV serology was negative. A plain X-ray film of the abdomen showed calcifications within the iliofemoral vessels. Doppler ultrasound of the penis and the iliac vessels revealed a complete lack of flow in the penis and minimal flow in the iliac and femoral arteries, as well as calcifications within the penis vessels.
A decision to perform a partial penectomy was made. The pathological study disclosed hyperplasia of the intimal layer, calcifications in the media with necrotic areas and bleeding within the penis. The postsurgical evolution was acceptable.
Calciphylaxis is a disorder of unknown etiopathogenesis. It is associated to hypercalcemia and/or hyperphosphatemia due to secondary hyperparathyroidism or to intake of calcium preparations and calcitriol.5 It appears in 1%-4% of the patients on hemodialysis. It was also described in patients on peritoneal dialysis, and very rarely in patients with renal transplantation or in those with end stage CRF, stages III and IV.6-8
The main approach to this condition should be the prevention, through monitoring of calcium levels and appropriate frequency of dialysis sessions. In experimental models it has been shown that early use of biphosphonates decreases the incidence.9 Parathyroidectomy is only beneficial in case of very PTH high levels.10
In the literature review we have found 35 cases of calciphylaxis with penis involvement.2,11,12 In 35% of them the treatment was conservative, in 53% surgery was underwent only if complications developed and in 12% surgery was early performed. The mortality rate was 58%, 61% and 25%, respectively. Sixty-eight percent of the cases evolved to moist gangrene (2,11). If the penis is involved the mortality reaches 69%.2,12
A high mortality of 50% at 6 months has been reported when penis necrosis develops in patients with DM and endstage CRF.13 DM, high blood pressure, end-stage CRF and dyslipidemia accelerate the atherosclerotic angiopathy, and they are the main risk factors for this entity.
Penis calciphylaxis is an infrequent systemic presentation of end-stage CRF. Early diagnosis and appropriate management can be determinant for the evolution and the prognosis in these patients.
