Indolent Acremonium strictum infection in an immunocompetent patient

A 35-year-old housewife presented with an 11-year history of a painless les ion on the right cheek, which had enlarged over the last 2 years. She had n o history of travel or trauma. Various topical and systemic antimicrobial a nd antifungal agents, such as fluconazole, ketoconazole, sulbactam/ampicill in, and mupirocin, had been prescribed, with a probable diagnosis of pyoder ma. and blastomycosis, without significant benefit. Her medical history was otherwise unremarkable. Dermatologic examination revealed a well-circumscr ibed, erythematous, infiltrative, 8 X 10 cm plaque covering the right cheek and a 2 X 3.5 cm vegetative, ulcerated lesion on the chin (Fig. 1). There were no sinus tracts or grains. The following laboratory test results were within the normal limits: comple te blood count, blood biochemistry, urinalysis, immunoglobulins and complem ent levels, T lymphocyte, CD4 and CD8 cell counts, and response to mitogens . X-Rays of the chest and maxillar and mandibular bones were normal. Routin e bacterial cultures were negative. Skin biopsies and fungal and mycobacter ial cultures were taken with a preliminary diagnosis of deep fungal or myco bacterial infection. Dermatopathologic examination revealed irregular epidermal hyperplasia with follicular plugging. A dense nodular lymphohistiocytic infiltrate was obse rved within the reticular dermis, with many multinucleated giant cells and plasma cells. In higher magnification, even in hematoxylin and eosin sectio ns, large septate hyphae and spores were noticeable. Periodic acid-Schiff s tain revealed abundant fungal structures within the giant cells and extrace llularly throughout the inflammatory infiltrate (Fig. 2). Lymphocytes were rather sparse in comparison to the large amount of microorganisms within th e tissue. Fungal cultures were performed on Sabouraud's dextrose agar and, within 1 w eek of incubation, white fungal colonies were observed. On multiple passage s at 26 degreesC, white tufted colonies with a salmon-colored base had form ed (Fig. 3). Native preparations from the cultured colonies revealed septat e hyphae, and 90 degrees angled branches, together with phialides decorated with ellipsoidal conidia with rounded edges (Fig. 4). These findings were consistent with Acremonium strictum, a saprophytic fungus. Further laboratory examinations revealed no systemic involvement. Following the diagnosis of Acremonium infection, amphotericin B therapy and surgical excision of the tumoral lesion were planned, but the patient refused furth er treatment and failed to respond to our follow-up attempts.