Histoplasmosis on the Isthmus of Panama

SummaryResults of an investigation designed to ascertain the status of Histoplasma capsulatum on the Isthmus of Panama have been presented. The remarkable prevalence of intradermal sensitivity to histoplasmin, the high prevalence of pulmonary calcific foci in histoplasmin-positive, tuberculin-negative individuals, and the striking similarity of these findings to those reported from known histoplasmosis-endemic areas of North and Latin America, seemed to justify the deduction that unrecognized histoplasmosis was endemic in this region.This deduction was confirmed by the subsequent recognition of a fatal infection in a four month old child from Chilibre, Republic of Panama. The first human infection since the three original cases described here by Darling nearly 45 years ago, it was the first unquestionably indigenous one to be reported from the Isthmus of Panama.