The reddish-purple lesions are typical of Kaposi sarcoma in a patient with wasting syndrome, oral thrush, and lymphopenia characteristic of HIV infection with AIDS. Hepatitis C virus is unlikely to produce skin lesions or lymphopenia of this degree. Herpes simplex virus infections may be seen more frequently in HIV infection, but the lesions are typically vesicular and are located in the perioral or perianal regions. Hansen disease, caused by Mycobacterium leprae infection, may produce a faint reddish rash that fades, followed by hypopigmentation or anesthesia of affected skin and sometimes nodular deforming lesions developing over years. Staphylococcal skin infections tend to produce localized abscesses, such as furuncles and boils. Streptococcal skin infections may manifest as abscesses or as cellulitis.