Thrombotic thrombocytopenic purpura (TTP) is a particular form of thrombotic microangiopathy typically characterized by thrombocytopenia, microangiopathic hemolytic anemia, fever, neurological abnormalities, and renal dysfunction. TTP requires a rapid diagnosis and an adapted management in emergency. Daily sessions of therapeutic plasma exchange (TPE) remain the basis of management of TTP. Also, TTP is a rare disease that is fatal if it is not treated. We describe a case of a 60-year-old woman who complained of hematuria and right lumbar pain and was diagnosed clear cell renal carcinoma. The patient progressed with interferon-alpha (IFN-α) therapy, and she was treated with sunitinib. At 8 weeks after the therapy, the patient presented with pallor, weakness, and widespread ecchymosis. After evaluation of clinical and laboratory findings, the patient was diagnosed as TTP. The drug was discontinued, and her symptoms improved.