Unusual Microorganism Causing Peritonitis

Introduction: A 75 Y/O/F patient has been doing flawless CAPD for 6-7 years. She developed mild but persistent abdominal pain 4 days before presenting for evaluation. Patient had peritoneal signs, PD effluent was cloudy and cell count was 2,400 cells with 100% polymorphs. PD effluent culture grew Streptococcus parasanguinis, a gram positive bacterium that is a member of the Streptococcus viridans group, and normal oral flora.. Patient therefore met criteria to diagnose peritonitis. Case Description: This 75 Y/O patient was trained appropriately to do home CAPD & had never experienced prior episodes of peritonitis. The S. parasanguinis is a member of the Streptococcus viridians group and is one of the major early colonizers of dental surfaces. This organism has cell surface structures, including pili & fimbriae, that contribute to biofilm formation and adherance to oral surfaces. It has been implicated in the development of dental plaque and infective endocarditis. By extension this bacterium could become an “opportunistic” pathogen causing an inflammatory response when introduced to peritoneal surfaces. Under most circumstances S. parasanguinis would be an unusual cause of peritonitis. But its presence as normal oral flora suggested that peritonitis became a result of touch contamination from a break in sterile technique by failing to wear a mask, not washing hands, not wearing gloves, and allowing grandchildren to be in the room during CAPD exchanges.. Patient was treated successfully with intraperitoneal vancomycin and was referred to her dental hygienist to improve her oral hygiene. Discussion: The success of any home PD program must rely on selecting patients who will be compliant, have good hand eye coordination, and are reliable in following sterile technique in an appropriate home environment. Importantly to reinforce importance of sterile technique and to minimize outbreaks of peritonitis, a refresher training course every 6 months for all patients on PD could be recommended with little inconvenience to trainer and trainee. In addition this case report highlights that maintaining good oral hygiene has been an overlooked aspect of care of patients doing home PD. This case suggests self-contamination of her PD fluid by deviating from her sterile technique. Because poor oral hygiene may contribute to the risk of peritonitis by touch contamination we recommend maintaining good oral hygiene as part of standard of care.