Relapsing Polymicrobial Peritoneal Dialysis Associated Peritonitis Caused by Rare Non Fermenting Gram-Negative Pathogens: A Case Report

Peritoneal dialysis (PD)-associated peritonitis caused by rare non-fermenting Gram-negative organisms remains a diagnostic and therapeutic challenge, particularly in the setting of prolonged antibiotic exposure and biofilm formation. We report the case of a 44-year-old male PD patient who developed relapsing, polymicrobial PD-associated peritonitis involving Elizabethkingia miricola, Brevundimonas diminuta, Stenotrophomonas maltophilia, and Staphylococcus haemolyticus. The case highlights the clinical relevance of slow-growing, biofilm-forming, multidrug-resistant organisms and underscores the importance of timely PD-catheter removal. This report also contextualizes the pathogens within the current literature and discusses the risk of misclassifying these organisms as contaminants.