Aureimonas altamirensis (A. altamirensis) is a bacterial specie from the caves of Altamira, Cantabria, Spain; considered as an environmental pollutant, but isolated for the first time in biological samples in 2008 by Luong et al., it is a potential human pathogen, with a variable clinical presentation.1,2

A case of peritonitis due to A. altamirensis, isolated in the ascites fluid of an oncological patient, has been described in the literature,3 no cases of peritonitis due to this micro-organism have been reported in patients on peritoneal dialysis (PD).

Below, we present a case of peritonitis due to A. altamirensis, in a patient on PD and we describe its clinical importance.

The patient is an 81-year-old male, with stage 5 chronic kidney disease (CKD) in PD program, with incremental modality (IPD), with a night exchange with 2.3% glucose, who presented abdominal pain of less than 24 h of evolution, along with cloudy fluid in the peritoneal exchange. Not clinical symptoms at any other level.

By Physical exam appears to be haemodynamically stable and afebrile, abdominal tenderness, preserved peristalsis, not painful at palpation and no signs of peritoneal reaction. The exit hole of the peritoneal catheter showed no inflammatory signs.

Among the complementary tests, a cell count was performed in the peritoneal fluid, which showed 827 leukocytes/μl, with 66% of neutrophils, so empirical treatment of peritonitis was established in relation to the technique with vancomycin and intraperitoneal ceftazidime. No imaging tests were performed.

In the culture of peritoneal fluid A. altamirensis resistant to gentamicin and tobramycin was isolated; sensitive to piperacillin tazobactam, ceftazidime, ciprofloxacin, trimethoprim sulfamethoxazole and amikacin. According to these results, antibiotic monotherapy with ceftazidime was maintained for 3 weeks with good response, with a cell control in peritoneal fluid of 70 leukocytes/μl, at 48 h.

The genus Aurantimone, described by Denner et al.4 in 2003, covers 4 species from environmental sources, including A. altamirensis, a gram-negative aerobic bacillus of marine waters.5 Initially it was considered a pollutant derived from the environment and/or water sources, but in recent years it has been isolated in biological samples, such as in the sputum of patients with cystic fibrosis, pleural effusion, eye infections (keratitis, corneal ulcers) and even in blood cultures of immunosuppressed patients.2,6,7

In a review of the literature, there are only a few cases published in which A. altamirensis is identified as a pathogen in humans: peritonitis in a patient with stage IV cholangiocarcinoma with peritoneal carcinomatosis3; 2 cases of pleural effusion described by Tellez-Castillo et al., with isolation of A. altamirensis in pleural fluid, one of the patients had a gastric adenocarcinoma8; lastly, 2 cases of bacteriemia due to A. altamirensis, one of them associated with a scrotal infection, in a pluripathological patient with stage 4 CKD7; and another in a patient with multiple myeloma, Bence-Jones type.2

It seems that all these cases would have as a common feature, an important comorbidity that conditions a situation of immunosuppression of variable importance. A. altamirensis could be considered as an opportunistic pathogen, which would cause the disease in patients weakened by an underlying disease.

From the epidemiological point of view, the patient did not report risk behaviours such as contact with animals, intake of contaminated food or untreated water, in our case we would have as the possible factors favouring infection: a dysfunctional immune system, typical of CKD patients on dialysis and the presence of a foreign body (PD catheter), on which, the bacterium has the ability to generate a biofilm, as described in one of the cases of bacteraemia, where the micro-organism was isolated in a blood culture taken from a venous reservoir, of the port-a-cath type.2

In our opinion, this is a case of great interest because it is the first peritonitis due to A. altamirensis in a patient on peritoneal dialysis, making it clear that, although in the literature it is described as of doubtful pathogenicity in our patients (with a higher comorbidity than usual), this becomes more apparent. It should also be noted that, although there is little experience in the treatment of A. altamirensis infections, in our case the pattern of empirical treatment of peritonitis on PD: ceftazidime plus vancomycin, was fully effective, with the resolution of the clinical picture.