Successful treatment of renal malakoplakia via the reduction of immunosuppression and antimicrobial therapy after kidney transplantation: a case report.

Malakoplakia is a rare, granulomatous disease that usually affects immunocompromised individuals and is generally associated with poor graft and patient survival. We present a case of renal malakoplakia after kidney transplantation (KT). A 33-year-old female patient with chronic kidney disease underwent living-donor KT at Severance Hospital. The patient was administered 375 mg/m² rituximab due to high panel reactive antibodies. Immunosuppression was initiated with 1.5 mg/kg anti-thymocyte globulin and intravenous methylprednisolone and maintained with tacrolimus, oral methylprednisolone, and mycophenolate mofetil (MMF). Six months after KT, the patient was hospitalized for a urinary tract infection with an elevated serum creatinine level of 3.14 mg/dL. Renal biopsy revealed malakoplakia involving the renal parenchyma. Upon this diagnosis, the dose of tacrolimus was reduced and MMF was stopped. Fluoroquinolone was used for 16 days, and the trimethoprim/sulfamethoxazole dose was doubled for 6 days. The patient was hospitalized for 3 weeks and closely observed during outpatient visits. Follow-up ultrasonography revealed mass-like lesions of renal malakoplakia, which disappeared 5 months after diagnosis. The serum creatinine level decreased to 1.29 mg/dL 28 months after diagnosis. Our results suggest that renal malakoplakia can be successfully treated by the reduction of immunosuppression and sustained antimicrobial therapy.