Ulcerated lesion of the alveolar ridge

Oral histoplasmosis in an HIV-negative patient

Histoplasmosis is a deep mycosis caused by Histoplasma capsulatum, which has been found in soil with accumulated excreta of bats and birds. This disease has variable clinical findings with only pulmonary or systemic involvement. Upper aerodigestive lesions are found mainly associated with systemic disease, affecting particularly patients with immunosuppression conditions mainly caused by HIV. However, it is uncommon in immunocompetent patients. This report describes a case of oro-laryngeal-esophageal histoplasmosis in a HIV-seronegative patient without detectable systemic involvement.

Aspects of fungal pathogenesis in humans

Fungal diseases have become increasingly important in the past few years. Because few fungi are professional pathogens, fungal pathogenic mechanisms tend to be highly complex, arising in large part from adaptations of preexisting characteristics of the organisms' nonparasitic lifestyles. In the past few years, genetic approaches have elucidated many fungal virulence factors, and increasing knowledge of host reactions has also clarified much about fungal diseases. The literature on fungal pathogenesis has grown correspondingly; this review, therefore, will not attempt to provide comprehensive coverage of fungal disease but focuses on properties of the infecting fungus and interactions with the host. These topics have been chosen to make the review most useful to two kinds of readers: fungal geneticists and molecular biologists who are interested in learning about the biological problems posed by infectious diseases, and physicians who want to know the kinds of basic approaches available to study fungal virulence.

Chronic pulmonary histoplasmosis with an oral lesion

Histoplasmosis is a fungal disease resulting from inhalation of airborne spores of the organism Histoplasma capsulatum. The disease is endemic to the Ohio and Mississippi river valleys. Oral lesions are not common, but when present, they are usually associated with the severe disseminated form of histoplasmosis. This particular case is presented as an example of chronic pulmonary histoplasmosis in which a localized gingival lesion represented the initial clinical manifestation of the disease. Diagnosis was based on a positive biopsy and the results of chest radiographic examination. If, as in this case, serologic, hematologic, and physical examination results are negative, the biopsy of suspicious lesions is of paramount importance to the clinical differential diagnosis.

Oral histoplasmosis: diagnostic complication and treatment

Intraoral histoplasmosis is difficult to diagnose, both because the clinician fails to be aware of it and because the lesion has clinical similarities to other disease entities, creating a misleading clinical impression. Effective communication between clinician and pathologist is essential, if one is to arrive at an accurate diagnosis and provide the best treatment. A new antimycotic agent, ketoconazole, is now available for oral administration. Studies indicate that it has major therapeutic advantages and significantly lower toxicity than comparable antimycotic agents.