Refractory peritoneal dialysis-associated peritonitis caused by Mycobacterium tuberculosis identified by mNGS: a case report.

BACKGROUND: Peritoneal dialysis-associated peritonitis (PDAP) is a common complication in patients undergoing peritoneal dialysis (PD) and may lead to technique failure or poor prognosis. Tuberculosis-related peritonitis in this setting is rare and difficult to diagnose because of nonspecific clinical manifestations and frequently negative conventional microbiological tests. Reporting such cases may help improve awareness and diagnostic strategies.

CASE PRESENTATION: We report the case of a 34-year-old woman with systemic lupus erythematosus and end-stage renal disease who was receiving maintenance peritoneal dialysis. She presented with fever, abdominal pain, and diarrhea. Repeated conventional bacterial and fungal cultures of peritoneal dialysis effluent and blood were negative, and empirical antibiotic therapy failed to achieve sustained clinical improvement. Metagenomic next-generation sequencing of the peritoneal dialysis effluent detected Mycobacterium tuberculosis, providing supportive diagnostic information. Based on the combined clinical presentation, molecular findings, and immunological testing, anti-tuberculosis therapy was initiated. The patient's symptoms gradually resolved, and peritoneal dialysis was temporarily suspended for 11 days before being successfully resumed. No recurrence of peritonitis was observed during a 6-month follow-up period.

CONCLUSIONS: This case highlights the diagnostic challenges of tuberculosis-related peritonitis in patients undergoing peritoneal dialysis. Metagenomic next-generation sequencing may serve as a useful adjunctive diagnostic tool in selected patients with persistent symptoms and repeatedly negative conventional cultures, facilitating earlier diagnosis and appropriate management.