Sporotrichosis is a human and animal disease caused by species of the Sporothrix schenckii complex. It is classically acquired through traumatic inoculation of fungal elements. Most frequently, sporotrichosis presents as a fixed cutaneous or as a lymphocutaneous form. A much smaller number of cases occur as cutaneous disseminated and disseminated forms. These cases require immediate diagnosis and management to reduce morbidity and mortality. We present the case of a 34-year-old male patient in whom the first presentation of HIV infection was a rapidly progressive sporotrichosis with multiple cutaneous lesions, a high fungal burden in tissues, and pulmonary involvement. He had an extremely low CD4 cell count (06/mm3). Treatment with amphotericin B deoxycholate led to complete clinical resolution. Sporotrichosis remains a neglected opportunistic infection among HIV-infected patients in Rio de Janeiro state, Brazil, and awareness of this potentially fatal infection is of utmost importance if treatment is not to be delayed and if potentially devastating complications are to be avoided.