Kidney Transplant Outcomes in Patients with Atypical Hemolytic Uremic Syndrome

Background: Atypical hemolytic uremic syndrome (aHUS) is a rare disorder with a high probability of recurrence after a kidney transplant and can adversely affect the graft outcome. Our objective was to assess the transplant outcome of patients with aHUS who had undergone a kidney transplant.

Methods: We retrospectively included patients who had undergone a kidney transplant and been diagnosed with aHUS based on an anti-complement factor H (AFH) antibody level >100 AU/mL and the presence of a genetic abnormality in complement factor H (CHF) or CHF-related (CFHR) genes. Data were analyzed with descriptive statistics.

Results: Among 47 patients with AFH antibody levels >100 AU/mL, 5 (10.6%) had undergone a kidney transplant. The mean age was 24.2 years, and all were male. Atypical hemolytic uremic syndrome was diagnosed before transplant in 4 (80.0%) cases, whereas 1 was diagnosed after transplant owing to disease recurrence in the transplanted graft. Genetic analysis of all cases revealed one or more abnormalities in CFH and CFHR genes 1 and 3. With an average of 5 sessions of plasma exchange and the use of rituximab in 4 cases, there was a reduction in the disease severity with no recurrences in the post-transplant period. At the latest follow-up of 223 days, the mean serum creatinine level was 1.89 mg/dL, indicating good graft function.

Conclusions: Among patients diagnosed with aHUS, the use of pre-transplant plasma exchange and rituximab can be beneficial in terms of preventing graft dysfunction and reducing disease recurrence in the post-transplant period.