Shiga Toxin-Producing Escherichia coli-Associated Hemolytic Uremic Syndrome in Adult Kidney Transplant Recipients

Shiga toxin (Stx)-producing Escherichia coli (E coli)-associated hemolytic uremic syndrome (STEC-HUS) is an acquired form of thrombotic microangiopathy (TMA) caused by food and waterborne infection. It remains the leading cause of acute renal injury (AKI) in children. In adults, STEC-HUS is less common but often more severe. Data on STEC-HUS in kidney transplant recipients (KTRs) are limited.

We conducted a retrospective study involving adult KTRs diagnosed with STEC-HUS between January 2012 and April 2022 across 15 French nephrology centers. We aimed to characterize the clinical, biological, and microbiological features of STEC-HUS in this population, its management, and outcomes.

A total of 35 adult KTRs were included. The annual incidence was estimated at 14.4 cases per 100,000 KTRs. Six and 29 patients presented with localized intrarenal or systemic TMA, respectively. The median time from transplantation to STEC-HUS diagnosis was 3 (1.2-6.2) years and the mean age at diagnosis was 57 ± 13 years. Neurological and cardiac complications occurred exclusively in patients with systemic TMA. AKI and significant proteinuria were observed in 89% and 94% of patients, respectively. All patients requiring dialysis exhibited systemic TMA (38%). Treatment included azithromycin, eculizumab, and conversion from calcineurin inhibitors (CNIs) to belatacept. Graft loss and mortality rates were 26% and 9%, respectively.

This study highlights that STEC-HUS represents a serious complication in KTRs, significantly impairing renal and overall survival. It should be systematically considered in cases of de novo posttransplant TMA, whether in the absence of prodromal diarrhea or in localized intra-renal presentations.