In AIDS-associated Kaposi sarcoma, which statement is correct?

• A. HHV-8 is the viral requirement and HIV is a cofactor
• B. EBV is the viral requirement and HIV is a cofactor
• C. HHV-6 is the viral requirement and HIV is a cofactor
• D. HPV is the viral requirement and HIV is a cofactor

Answer: (A)

In Kaposi sarcoma associated with AIDS, the essential viral trigger is infection with HHV-8 (Kaposi sarcoma–associated herpesvirus). The HIV infection acts as a cofactor because the resulting immunosuppression allows HHV-8–infected endothelial cells to proliferate and form the characteristic vascular spindle-cell lesions. HHV-8 is required for KS to develop, whereas HIV’s role is to permit tumor growth by weakening immune surveillance. The other viruses listed are not the drivers of KS: EBV is linked to certain lymphoid and epithelial cancers, HHV-6 causes roseola, and HPV is linked to cervical and some anogenital cancers. In AIDS patients, restoring immune function (e.g., with antiretroviral therapy) can lead to regression of KS, illustrating the important cofactor role of immune status.