Kaposi Sarcoma (KS) is a vascular tumor commonly associated with HIV/AIDS. There is unusual presentation of KS in a non-HIV patient, initially diagnosed as small vessel vasculitis. Early recognition and accurate diagnosis are important for the patient’s best management.

A 68-year-old male presented with spontaneous bluish-black patches on his extremities, swelling, pain, and bullae on his toes. Initial workup, including negative ANA and ANCA markers, pointed to small vessel vasculitis, with autoimmune, hematologic, and occlusive diseases considered. Peripheral vascular occlusion was ruled out, and a biopsy showed granulomatous vasculitis. Despite corticosteroid treatment, the lesions worsened. Five months later, the patient developed violaceous papules, plaques, and nodules. A second biopsy confirmed Kaposi Sarcoma (KS) with positive CD34 and HHV-8 stains. Restaining the initial biopsy also revealed KS. Treatment with Doxorubicin was initiated, but the disease progressed, affecting the gastrointestinal system. The patient’s condition deteriorated, and he died from complications of KS.

This case underscores the importance of considering Kaposi Sarcoma in HIV-negative patients with vascular lesions. The initial diagnosis of vasculitis, confirmed by granulomatous changes, delayed the KS diagnosis. Restaining the first biopsy later confirmed the presence of KS from the onset. The extensive skin and gastrointestinal involvement made management with Doxorubicin difficult, leading to a poor outcome.