Multimodal Management of Anti-GBM Disease Complicated by Secondary Complement-Mediated Thrombotic Microangiopathy in a Patient Intolerant to Plasma Exchange: A Case Report.

BACKGROUND

Anti-glomerular basement membrane (anti-GBM) disease complicated by thrombotic microangiopathy (TMA) is rare and clinically challenging. In the setting of severe infection and active autoimmune disease, complement activation may reflect a secondary process rather than primary atypical hemolytic uremic syndrome (aHUS). Therapeutic plasma exchange (TPE) is standard therapy for anti-GBM disease, but alternative antibody removal strategies are required when TPE is not tolerated.

CASE PRESENTATION: We describe a 46-year-old female with anti-GBM disease who developed TMA with preserved ADAMTS13 activity (72.04%) and 2.3% schistocytes on peripheral smear. Soluble C5b-9 was elevated in the context of severe concurrent infection. TPE was discontinued due to intolerance (oxygen desaturation, fever, and dizziness). Seven sessions of protein A immunoadsorption (PAIA) were performed for selective antibody removal, and anti-GBM antibody levels decreased from > 400 to 20.80 RU/mL during treatment. Eculizumab was administered on Days 7, 14, and 30, for persistent complement activation. Hematologic and biochemical parameters stabilized and gradually improved during combined therapy.

CONCLUSION

This case suggests that PAIA may represent a feasible alternative antibody removal strategy in anti-GBM disease intolerant to plasma exchange. In selected cases of secondary complement-mediated TMA with ongoing complement activation, short-term complement inhibition may contribute to disease stabilization; however, a definitive causal relationship cannot be established in a single case.