Imported Histoplasmosis: Two Distinct Profiles in Travelers and Immigrants

Background: Histoplasmosis is acquiring importance in nonendemic areas due to the increase in travel and immigration, being the most common systemic mycosis acquired by European travelers. Epidemiological studies show that the incidence of Histoplasma infection in these patients may be higher than previously believed and a wide clinical spectrum of disease may be observed.

Methods: Cases of histoplasmosis diagnosed at a Tropical Medicine Referral Unit in Madrid, Spain, during the period January 1996 to December 2006 were reviewed.

Results: Ten cases of histoplasmosis in travelers and immigrants are described. Five HIV-positive patients (four immigrants and one expatriate) all presented with progressive disseminated disease. Five HIV-negative patients (travelers) all presented with pulmonary disease: four with an acute pulmonary form (one with pleural involvement) and one patient was found to have residual pulmonary disease (lung nodule). Three of the travelers also had rheumatologic manifestations (arthromyalgias or arthritis).

Conclusions: Clinicians in nonendemic areas may be faced with patients with a diagnosis of histoplasmosis and although Histoplasma infection can have a varied and nonspecific clinical presentation, imported histoplasmosis may have two distinct profiles. Previously, healthy travelers may be exposed in endemic areas and mainly develop acute forms of the disease with a favorable outcome. Immigrants or expatriates from endemic areas who may be immunosuppressed due to HIV infection may experience reactivation of latent disease developing disseminated forms with high mortality rates. This infection should be considered in the differential diagnosis of diseases affecting travelers and immigrants.