Abstract: SA-PO0690
Successful Withdrawal of Complement Inhibition in Atypical Hemolytic Uremic Syndrome with Complement Gene Variants: A Pediatric Case Series
Session Information
- Glomerular Diseases: Complement-Mediated Glomerulopathies and Infection-Related GN
October 24, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Hanson, Valeria, University of New Mexico, Albuquerque, New Mexico, United States
- Singh, Namita, University of New Mexico, Albuquerque, New Mexico, United States
Introduction
Atypical hemolytic uremic syndrome (aHUS) results from dysregulated activation of the cell surface bound alternative complement pathway, with approximately 60% of cases linked to genetic complement abnormalities. Patients typically present with thrombotic microangiopathy (TMA) triad of thrombocytopenia, microangiopathic hemolytic anemia, and acute kidney injury. Early recognition and prompt complement targeted therapy are essential to preserve kidney function, prevent progression to dialysis, and support better long term outcomes.
Case Description
Three pediatric patients aged 8 –15 years were diagnosed with aHUS, all presented with the classic TMA triad; kidney biopsy in one patient showed severe acute TMA with cortical necrosis, while the other two were diagnosed clinically based on symptoms and laboratory findings. Genetic testing identified heterozygous CD46 mutations in two patients. The third patient carried an MTHFR mutation, which is not directly associated with aHUS but may have contributed as a risk factor.
All patients started treatment with plasma exchange and Eculizumab, and transitioned to Ravulizumab, with complete renal recovery and successful discontinuation of dialysis in 2 cases. After therapy durations ranging from 1.5 to 9 years, Ravulizumab infusions were discontinued in all 3 adolescents during transition process to adult nephrology care, with no episodes of relapses thus far. Interestingly, the patient with the MTHFR variant developed focal segmental glomerulosclerosis eleven years later.
Discussion
This case series highlights successful management of aHUS using C5 inhibitor therapy in pediatric patients with complement related genetic abnormalities, and sustained remission years after treatment discontinuation. Nephrologists should consider individualized treatment plans for aHUS, considering genetic risk factors and clinical response.