Interruption of antifungal secondary prophylaxis in AIDS-related histoplasmosis

The clinical data of 21 patients, suffering AIDS-related histoplasmosis, who were able to interrupt antifungal secondary prophylaxis, after achieving a partial restoration of the cell mediated immunity by HAART administration, are presented. They were 16 males and five females, whose ages varied between 32 and 54 years (mean = 38.5 years). All of them presented disseminated progressive forms of histoplasmosis, with multiple locations (skin, mucous membranes, liver, spleen, lymph nodes and lungs). The majority of the cases suffered other concomitant diseases (specially tuberculosis and Kaposi sarcoma), 66.6 % of the patients had less than 50 CD4+ cells/microl at the start of treatment and the average viral burden was 278,385 RNA copies/ml. The initial treatment consisted in 400 mg/day of itraconazole, by oral route, in 14 cases and the remaining seven patients were treated with amphotericin B, intravenously, at a daily dose of 0.7 mg/kg of body weight. One patient who did not tolerate amphotericin B and presented a partial response to itraconazole, was treated with posaconazole orally at a daily dose of 800 mg. Fourteen patients received oral itraconazole at a daily dose of 200 mg as a secondary prophylaxis, the remaining three patients were treated with intravenous amphotericin B, 50 mg twice a week. After HAART for an average lapse of 16.7 months (10 to 32 months), five cases showed CD4+ cells counts above 150 cells/microl and the remaining 16 presented more than 200 cells/microl; 18 of them had undetectable viral burden and all cases were asymptomatic. The follow up after secondary prophylaxis discontinuation varied between six months and six years (mean= 33.6 months). Twenty out of 21 patients (95 %) were clinically stable, without any manifestation of relapses, including two patients who abandoned HAART. One patient, who discontinued HAART, contracted a fatal bacterial pneumonia. Even though the limited number of cases, the data presented in this study seem to suggest that it is possible to interrupt antifungal secondary prophylaxis of histoplasmosis, when the patient is clinically asymptomatic and the CD4+ cells counts are above 150 cells/microl.