Atypical Hemolytic Uremic Syndrome (aHUS) with Hepatocellular Adenoma: Complement Dysregulation and Multidisciplinary Management Challenges

Introduction: aHUS, a complement-mediated thrombotic microangiopathy (MAHA, thrombocytopenia, AKI), while its association with solid tumors remains unclear. Here we report a rare case of aHUS with hepatocellular adenoma, exploring the complement-tumorigenesis interplay and multidisciplinary care. Case Description: Clinical Features: A 28-year-old male presented with fatigue, oliguria accompanied by hemolytic anemia (Hb 101→59 g/L, ↑LDH, schistocytes), thrombocytopenia (BPC declined >50%),and elevated Scr (75→554μmol/L) , . Renal biopsy showed TMA and ATN. Anti-CFH antibody positive, sC5b-9＞3ULN, and CFI＞2ULN. ADAMTS13 activity was normal. Abdominal CT showed multifocal liver masses (largest 130×240 mm). Histopathology confirmed hepatocellular adenoma with focal carcinomatous transformation (GPC3+, HSP70+, Ki-67.3%). Management: Eculizumab (900 mg qw ×4→1200 mg q2w×11) combined with DFPP and CRRT from 2024-10-9, to 2025-5-12. Scr decreased from 554 to 158 μmol/L, with dialysis discontinued by 2025-1-2; Five times of sessions of transarterial chemoembolization stabilized tumor progression；Pneumonia were managed with antibiotics and supportive care. Discussion: Anti-CFH antibody-positive aHUS requires differentiation from TTP/secondary TMA. Normal ADAMTS13 activity and elevated complement markers (sC5b-9, CFH antibody, CFI) confirmed aHUS. Initial onset with hepatic lesions may overshadow renal involvement, highlighting the necessity of complement profiling. Tumors may trigger aHUS, in return, complement activation may drive carcinogenesismechanisms via inflammation. Eculizumab improved renal function without tumor progression despite immunosuppression risks, suggesting complement blockade safety. Clinical implications: screen for complement dysregulation in TMA with hepatic lesions; initiate eculizumab early despite comorbidities; prioritize research on complement-hepatorenal crosstalk.Figure aHUS with Hepatocellular Adenoma