K HAWKE1, I ISMAIL1, A LEE1, M FAHIM2, A GUPTA1
1Department of Nephrology, Toowoomba Hospital, Queensland; 2Department of Nephrology, Princess Alexandra Hospital, Queensland
Aim: We present a lung transplant patient with a diagnosis of sepsis secondary to M morganii PD peritonitis, requiring PD catheter removal despite prompt antimicrobial therapy.
Background: Morganella morganii is a rare cause of peritoneal dialysis (PD) peritonitis. Resistant strains of this opportunistic pathogen have emerged with widespread use of third-generation cephalosporins.
Methods: A 59 year old man had been on peritoneal dialysis for eight weeks because of end-stage renal disease secondary to calcineurin inhibitor toxicity. His background was bilateral lung transplant seven years prior, with current immunosuppressant regimen comprising cyclosporine, azathioprine and prednisolone.
While admitted for pulmonary fungal infection, he developed abdominal pain and turbid PD fluid. Physical examination revealed a tender abdomen, tachycardia and erythematous catheter exit site. Peritoneal effluent contained white cells 9000 x 106/L (83% polymorphonuclear leukocytes), which increased to 26 400 (95% polymorphs) the following day. Computed tomography of the abdomen showed greater omentum fat stranding and sigmoid diverticulitis, but no perforation.
Results: We diagnosed PD-related peritonitis and gave empiric antibiotic therapy (intraperitoneal gentamicin and vancomycin). Cultures of the peritoneal fluid yielded M. morganii (sensitive to gentamicin) and low numbers of Enterococcus faecium (sensitive to vancomycin). PD catheter was removed after three days of clinical deterioration and new haemodynamic instability. Catheter tip was culture-positive for M. morganii.
Conclusions: To our knowledge, this is the first case of M. morganii PD peritonitis in a transplant setting. It supports a high index of suspicion for rare organisms in immunocompromised hosts. The organism’s sensitivity to gentamicin suggests current empiric therapy guidelines are appropriate in transplant patients. The clinical course was more severe than those described previously, highlighting M. morganii’s pathogenic potential in transplant recipients.