Nivolumab-Induced Warm Autoimmune Hemolytic Anemia and Pancytopenia.

Immunotherapy-related adverse events arise from the disinhibition of the body's own immune system. A 76-year-old Caucasian man undergoing treatment with nivolumab monotherapy for metastatic clear cell renal carcinoma presented to our hospital with symptoms of fatigue and easy bruising. Laboratory analysis confirmed warm autoimmune hemolytic anemia with pancytopenia. Bone marrow biopsy demonstrated no evidence of malignancy or marrow failure. He was initiated on guideline-driven therapy with corticosteroids and experienced complete resolution of cytopenias by the three-month follow-up.