The Use of Intraperitoneal Ampicillin in a Patient With Enterococcus faecalis Peritonitis

Introduction: Peritoneal dialysis (PD) – associated peritonitis is a serious complication of peritoneal dialysis (PD). The 2022 International Society of Peritoneal Dialysis (ISPD) guidelines do not recommend intraperitoneal (IP) ampicillin for treatment of Enterococcal PD – associated peritonitis. To date, there is no in vivo data to support use of IP ampicillin for the treatment of Enterococcus faecalis. Case Description: A 69-year-old man with a past medical history of end stage kidney disease (ESKD) requiring continuous cycling peritoneal dialysis (CCPD) was admitted to the hospital and treated for peritonitis with E. faecalis. The patient’s CCPD prescription was 2.5% Dianeal with 5 total exchanges. IP ampicillin was added to the first 4 exchanges and additional ampicillin was added to the last fill. The patient successfully completed the treatment course with clinical cure. Discussion: The use of IP ampicillin for E. faecalis peritonitis is controversial and previously lacked compelling clinical evidence for or against its use. This case demonstrates treatment of peritonitis using a modified dosing strategy with ampicillin added to each CCPD exchange and last fill. The loss of ampicillin antimicrobial activity reported in vitro with E. faecalis was not supported by this case.