Disseminated histoplasmosis: A comparative study of the clinical features and outcome among immunocompromised and immunocompetent patients.

ABSTRACT

Background. Disseminated histoplasmosis is a chronic granulomatous disease caused by the dimorphic fungus, Histoplasma capsulatum. Clinical presentation can vary from the acute pulmonary to the chronic disseminated form. In India, disseminated histoplasmosis often presents with pyrexia of unknown origin with a presentation similar to ‘disseminated tuberculosis’ involving the adrenal glands and bone marrow. Due to rarity of the disease, data are lacking regarding its clinical presentation and outcome among immunocompromised and immunocompetent patients. Methods. During January 2000 to December 2010, we identified 37 patients of disseminated histoplasmosis and attempted to characterize the differences between immunocompromised and immunocompetent patients. Demographic characteristics, clinical presentation, risk factors, laboratory findings, diagnostic yield, treatment received and prognosis were noted and compared between the two groups. Results. Eleven of 37 patients with disseminated histoplasmosis were immunocompromised and 26 were immunocompetent. Comparison of their clinical features showed a higher frequency of skin lesions in the immunocompromised compared to the immunocompetent group (54.5% v. 11.5%). Pancytopenia and anaemia were more common among the immunocompromised (81.8%) compared to the immunocompetent (46.2%) group. In the immunocompromised patients, the diagnosis was made most often by bone marrow aspirate and culture (72.7%) compared to the immunocompromised group where the diagnosis was most often obtained by adrenal gland biopsy and fungal cultures (57.7%). The cure rate was significantly higher in the immunocompetent group (73% v. 45%). Conclusion. The clinical presentation and outcome of patients with disseminated histoplasmosis differs among immunocompromised and immunocompetent patients.