Endemic fungal pneumonia in immunocompromised patients.

The endemic fungi Histoplasma capsulatum, Coccidioides immitis, and Blastomyces dermatitidis tend to reside in specific geographic regions. The organisms are pathogenic in that they are able to produce clinical disease in both immunocompromised patients and in patients with normal immunity. These organisms have a variety of clinical presentations, some of which typically are seen in the normal host and others that are primarily encountered in persons with abnormal immunity. Although most of the cases are seen in endemic regions, they may occur in persons who at some time either resided in or traveled to an endemic region.