Nocardia asteroides peritoneal dialysis-related peritonitis: a case of successful treatment and return to peritoneal dialysis

Abstract

A 66-year-old male from rural Manukau, New Zealand, presented to hospital with 2 weeks of generalized abdominal pain and cloudy PD effluent. He had been on PD for 3 years, with only one previous episode of PD-related peritonitis secondary to Streptococcus oralis a year prior. Other significant co-morbidity included well-controlled Type 2 diabetes mellitus on diet therapy, hypertension, mild chronic obstructive airways disease and quiescent gout. On initial examination, the patient was afebrile with blood pressure of 140/70mmHg. Abdominal examination showed generalized tenderness and normal bowel sounds. The PD catheter exit site was normal. Microscopy of dialysate showed 1600 leucocytes, 86% of which were neutrophils, and no organisms. After initial investigations, antibiotic treatment was commenced for PD-related peritonitis with empirical intraperitoneal cephazolin and gentamicin. His dialysate sample was processed in our microbiology laboratory; this involved inoculation of 10 mL into both BacT/ALERT FA aerobic and FN anaerobic blood culture bottles (bioMerieux, Marcy-l’Etoile, France), with the deposit from 10 mL of centrifuged sample inoculated onto two sheep blood agar plates, incubated in 5% CO2 and anaerobically, and one chocolate agar plate incubated in 5% CO2. After 5 days incubation, the BacT/ALERT FA aerobic bottle was reported as growing a fungus. Since one of the enrichment broths had become positive, the primary agar plates were held longer than the usual 5 days, but remained culture negative after 21 days. The patient was therefore treated as fungal peritonitis with a change in his antibiotic regimen to fluconazole 200 mg orally on alternate days and removal of his PD