Butyricimonas virosa Peritonitis in Peritoneal Dialysis Patient: A Case Report and Review

Butyricimonas virosa is a Gram-negative bacillus, which was first discovered in rat faeces in 2009. To date, only seven human infections have been reported in literature. To our knowledge, this is the first reported case of peritoneal dialysis (PD)-related peritonitis due to B. virosa. A 65-year-old Chinese man presented to the hospital with complaints of dizziness and vomiting. On admission, the drained peritoneal dialysate was cloudy. He was empirically treated as a case of PD-related peritonitis with intraperitoneal (IP) cefazolin, ceftazidime, and gentamicin. B. virosa was isolated from peritoneal fluid sample and the antibiotics were changed to IP imipenem and amikacin. Three weeks after completion of the antibiotics, the patient presented again with cloudy peritoneal dialysate and blood stained diarrhoea. IP imipenem and amikacin were recommenced. Multiple peritoneal dialysate samples were sent to the microbiology laboratory, but this time no microorganism was isolated. Colonoscopy examination revealed the presence of extensive rectosigmoidal ulcerations. IP imipenem was replaced with IP piperacillin-tazobactam when the patient developed imipenem-associated neurotoxicity at Day 9 of treatment. The patient recovered fully after completing 3 weeks of IP piperacillin-tazobactam and 2 weeks of IP amikacin. This is the first reported case of PD-related peritonitis due to B. virosa. Susceptibility data for B. virosa are scarce, but a 3-week course of IP piperacillin-tazobactam, imipenem, or meropenem could be potentially useful in treating PD-related peritonitis caused by this organism.