An unusual case of peritoneal dialysis-associated bacterial peritonitis caused by Weeksella virosa.

Weeksella virosa is an atypical Gram-negative bacterium that does not grow on MacConkey agar. In this report, we present a 4-year-old female patient with Addison's disease and end-stage renal failure secondary to focal sclerosing glomerulosclerosis. Continuous ambulatory peritoneal dialysis had been performed, and 3 months later, the patient developed fever, diarrhea, and vomiting. Peritoneal fluid culture and dialysis fluid culture were positive for W. virosa. It was identified with Phoenix (BD, USA) and confirmed via 16S rRNA sequencing. It cannot be identified by Maldi Biotyper (Bruker). The isolate was found to be resistant to cephalosporins, ciprofloxacin, and amikacin by gradient test. Intraperitoneal cefepime was initiated but since antimicrobial susceptibility testing revealed cephalosporin resistance, therapy was changed to intraperitoneal meropenem. Following the removal of peritoneal dialysis catheter, fever, abdominal distention, and vomiting were resolved. Piperacillin, aztreonam, and carbapenems can be used for empirical therapy. Antimicrobial susceptibility testing should be performed to guide the choice of treatment. Removal of peritoneal dialysis catheter is an important step of management of this infection. To our knowledge, this is the first report of W. virosa in a pediatric patient and first report from Turkey.