Snapshot A 45-year-old man with a history of HIV infection presents to his primary care doctor for a rash. He had been on antiretroviral medications for his HIV infection for years. Six months ago, he lost his job and his insurance and ran out of medication 5 months ago. He had been feeling fine until a week ago when he developed a painless rash on his face, trunk, and legs. He has also had some night sweats and low-grade fevers. On physical exam, he has multiple scattered reddish purple macules and papules. There are also purple nodules on his oral mucosa. A skin biopsy reveals neoplastic spindle-shaped cells and a lymphocytic infiltrate. Introduction Classification human herpesvirus-8 (HHV-8) an enveloped, linear double-stranded DNA virus causes Kaposi sarcoma, a neoplasm of endothelial cells Epidemiology demographics endemic in Africa causes soft tissue tumors adults > children location skin, lungs, lymph nodes, and gastrointestinal tract risk factors HIV/AIDS acquired through sexual contact rarely seen in AIDS acquired through injection drug use post-transplant Pathogenesis HHV-8 inhibits tumor suppression pathways Associated conditions diabetes mellitus autoimmune hemolytic anemia Prevention highly active antiretroviral therapy (HAART) annual skin exam in those at risk Prognosis progression is slow recurrence is likely Presentation Symptoms B symptoms (fevers, night sweats, and weight loss) painless skin lesions may have pain associated with internal lesions Physical exam red or purple lesions of varying morphologies macules and patches papules and plaques nodules common on the face, oral mucosa, legs, and torso lymph nodes may be enlarged Studies Labs evaluate CD4+ count if AIDS is suspected Skin biopsy neoplastic spindle-shaped cells that form clefts and vascular channels lymphocytic infiltrate Making the diagnosis based on clinical presentation and confirmed with skin biopsy Differential Bacillary angiomatosis distinguishing factors rash manifests as dark red and purple papules, nodules, and plaques skin biopsy reveals neutrophilic infiltrate Treatment Management approach HAART in those with AIDS-related disease is mainstay of treatment patients should discontinue any immunosuppressants Medical vincristine indication AIDS-related disease interferon indication AIDS-related disease chemotherapy and radiation therapy indication widespread or rapidly progressing disease Complications Metastatic progression of disease