CUTANEOUS DISSEMINATED MYCOSIS IN A PATIENT WITH AIDS DUE TO A NEW DIMORPHIC FUNGUS

Purpose. To report on a new thermally dimorphic fungus causing cutaneo us disseminated mycosis in a patient with a terminal AIDS. Clinical ob servation and laboratory diagnosis. The patient was a 40-year old Ital ian woman who had never travelled abroad, and was intravenous drug use r who had been HIV positive for ten years. She suffered from a series of viral, hepatic and bacterial endocardial and pulmonary infections, followed during her last year by the development of generalised erythe matous, papular, ulcerated cutaneous lesions, emaciation, and vomiting . There were no pulmonary X-ray abnormalities or lymphadenopathy, but her CD4 counts were very low at 7/mm(3). Skin biopsies indicated that the patient was suffering from histoplasmosis and she was placed on a short course of amphotericin B, before she died, without autopsy. The last biopsy, stained with hematoxylin-eosin, showed a necrotic epiderm is, a exudative haemorrhagic reaction with polymorphonuclear cells and numerous histiocytes without epithelioid and giant cells. Periodic ac id-Schiff and Gomori methenamine stains revealed numerous intracellula r yeast-like cells with pleomorphic features. Most of the yeasts were small (2-4 mu m), oval or round with thin cell walls and occasional na rrow-necked budding cells, similar to Histoplasma capsulatum. A few la rger cells (8 to 15 mu m), were oval and spherical with thicker cell w alls, reminiscent of Blastomyces dermatitidis, but without the typical broad bud base. Slow growing cultures were obtained from the biopsy: a) at 25 degrees C on Sabouraud agar in a mycelial phase with a delica te conidial apparatus much like that of the two onygenalean dimorphic genera Blastomyces and Emmonsia; b) at 37 degrees C on BHI medium in a yeast phase similar to that of the cutaneous biopsy. There were no ad iaspores, like produced in vivo by Emmonsia parva or E. crescens. Conc lusion. The case was considered to be an AIDS terminal opportunistic f ungal infection caused by a new species of the genus Emmonsia, named E , pasteuriana.