A Patient with Peritoneal Dialysis-Related Nocardia Peritonitis

Introduction: As of 2020, there were only twelve reported cases of peritoneal dialysis (PD) related nocardia peritonitis. The following case is therefore unique and raises questions of antibiotic and PD management in this population. Case Description: A 78-year-old female with ESRD on PD presented with one day of abdominal pain, nausea, and vomiting. Initial vitals were notable only for mild tachycardia. Her exam was significant for tenderness to palpation in the right lower and upper quadrants. No erythema or purulent drainage was noted at her PD catheter site. Initial labs revealed a leukocytosis to 18k. CT abdomen confirmed catheter placement but deemed free air in the peritoneum “larger than expected.” The patient was started on ceftriaxone, metronidazole, and vancomycin. PD fluid analysis revealed 15000 cells with 86% PMNs, and the patient was switched from ceftriaxone to cefepime. On day 4, repeat fluid studies and symptoms were significantly improved, but peritoneal cultures resulted positive for nocardia. ID was consulted to discuss antibiotics and PD removal. Amikacin and catheter removal were considered but deferred due to logistical concerns and clinical improvement. The patient was discharged on trimethoprim-sulfamethoxazole (TMP-SMX). Unfortunately, the patient re-presented one month later with recurrent catheter-associated nocardia peritonitis. She improved with antibiotics but was unable to tolerate HD after PD removal and was eventually transitioned to hospice. Discussion: Nocardia associated peritonitis is a very rare diagnosis making it difficult to determine appropriate antibiotic and PD management. Nocardia is typically susceptible to TMP-SMX making it a reasonable choice. Amikacin is a more aggressive therapy with higher potential of salvaging the PD catheter. The International Society of Peritoneal Dialysis (ISPD) recommends PD catheter removal for peritonitis caused by nocardia. However, about half of reported cases were treated with catheter removal and the other half were not with relatively similar outcomes. With our patient, catheter removal was deferred given significant logistical constraints and clinical improvement. It is unclear whether more intensive antibiotics or rapid removal of her PD catheter would have improved our patient's outcome. The case underlines the importance of interdisciplinary cooperation and continued joint decision making between providers, patients and loved ones.