Malakoplakia in kidney transplant recipients: Three case reports.

Background: Malakoplakia is a rare chronic granulomatous disease associated with gram-negative infection, predominantly by Escherichia coli. It is induced by defective phagolysosomal activity of the macrophages. Malakoplakia commonly affects the urinary bladder but has been shown to affect any solid organ, including the native and transplanted kidney. However, isolated malakoplakia of the kidney allograft is rare. Transplant recipients with compromised immune systems are more likely to develop malakoplakia.

Case summary: We report three cases of kidney allograft parenchymal malakoplakia in kidney transplant recipients on immunosuppression that were successfully managed with good outcomes. We described the clinical characteristics of all the kidney allograft malakoplakia cases documented in the literature. A total of 55 cases of malakoplakia were reported in recipients with a history of kidney transplant. A total of 27 recipients had malakoplakia involving the allograft, and others had malakoplakia in other organs. The common presentations included allograft dysfunction, pyelonephritis, and allograft or systemic mass. Most recipients had favorable outcomes with appropriate management that included prolonged antibiotic therapy and adjustment of immunosuppression. We reviewed the published literature on all the cases of malakoplakia in kidney transplant recipients so far and summarized the etiology, management, and outcomes.

Conclusion: This case series provides an overview of the etiology, presentation, pathogenesis, and management of malakoplakia in kidney transplant recipients.