Peritoneal dialysis-associated peritonitis caused by Coxiella Burnetii: A case report

Rationale:Peritoneal dialysis (PD)-associated peritonitis (PDAP) is the leading cause of PD failure and discontinuation of PD. Several zoonotic pathogens could lead to the development of PDAP. Coxiella burnetii (C. burnetii) was a zoonotic pathogen and the cause of Q fever. However, reports of PDAP caused by C. burnetii are rare. We herein report the first case of PDAP caused by C. burnetii in mainland China.Patients concerns:A 45-year-old woman was admitted to our hospital with chief complaint of yellow and cloudy PD effluent for 2 days. She had undergone PD for 5 years due to end-stage renal disease. She was engaged in cattle and sheep breeding. The culture of PD effluent was negative, even for specific species, such as Mycobacteria and fungi.Diagnoses:The culture from the PD effluent tested positive for C. burnetii by adopting metagenomic next-generation sequencing on day 37. We diagnosed her as PDAP caused by C. burnetii.Interventions:Empirical treatment with multiple broad-spectrum antibiotics (including vancomycin, etimicin, piperacillin) was initially adopted. After identifying C. burnetii as the culprint as the PDAP, the regimen was changed to doxycycline (100 mg twice daily) and moxifloxacin (400 mg once daily) orally, leading to clinical improvement.Outcomes:The white blood cell count of the PD effluent decreased to within the normal range and the culture of PD effluent was negative for C. burnetii at the visit of 4 months after discharge. Also, there was no sign for recurrence.Lessons:Vigilance should be heightened for PDAP cases with negative culture of PD fluid and poor response to standard broad-spectrum antibiotic treatment, along with a history of cattle and sheep breeding. In such conditions, PD effluent should be tested to detect possible peritonitis caused by C. burnetii, even in patients without symptoms of fever. Prompt pathogen identification and appropriate treatment are crucial for clinical improvement of such cases.