Successful treatment of Nocardia asteroides peritonitis in a patient undergoing automated peritoneal dialysis and receiving immunosuppressive therapy.

Nocardiosis is an opportunistic infection especially in patients with underlying chronic debilitating disease or immunodeficiency. Nocardia peritonitis is an uncommon infection in peritoneal dialysis patients. Here, we report a case of peritonitis by Nocardia asteroides during automated peritoneal dialysis in a 35-year-old male patient who had prolonged immunosuppressive therapy to treat acute rejection of a nonfunctioning kidney allograft. The patient presented at our outpatient clinic with typical symptoms of acute peritonitis. The peritoneal fluid leukocyte count was 20,500 cells/microL, with 90% neutrophils. Gram staining showed gram-positive filamentous bacilli later identified as N. asteroides. After bacterial identification, the patient received trimethoprim 320 mg and sulfamethoxazole 3200 mg intravenously every 48 hours (TMP-SMX), plus amikacin 100 mg intraperitoneally daily. The immunosuppressive therapy was reduced. Peritoneal fluid cultures became negative after 1 week of treatment, concomitant with clinical improvement. Unfortunately, after 5 weeks of therapy, the patient developed hematologic side effects attributable to the TMP-SMX treatment. The TMP-SMX was suspended at that time, and the patient then received cefuroxime 500 mg by mouth and amikacin 100 mg intraperitoneally daily for a total of 12 weeks. The patient recovered completely and was discharged 3 months after onset of the peritonitis. Prolonged antibiotic therapy without catheter removal has not been previously described in immunosuppressed patients with APD peritonitis. The combination of amikacin and TMP-SMX may be safe and effective in APD patients who develop N. asteroides peritonitis.