Histoplasmosis clinically imitating cutaneous malignancy.

Disseminated histoplasmosis can have a varied presentation when it affects the skin. Presentation mimicking a cutaneous neoplasm is an uncommon manifestation. We present the case of an 86-year-old man presenting with a cutaneous lesion clinically suspicious for malignancy that was ultimately determined to be his first clinical manifestation of disseminated histoplasmosis after biopsy for histopathologic analysis. Microscopically, the lesion was a nodule with an eroded epidermis overlying a dense dermal inflammatory process. The infiltrate was characterized by numerous epithelioid histiocytes admixed with acute and chronic inflammation. On closer inspection, numerous 2-4 mum intracellular spores surrounded by a clear halo were identified. The organisms were highlighted with periodic acid schiff (PAS) stain. We present this case to highlight a unique presentation of disseminated histoplasmosis. Although this presentation is uncommon, it serves as a reminder that histopathologic confirmation of clinical diagnoses is important before undertaking more invasive procedures such as excision. Copyright Blackwell Munksgaard 2008.