English: This patient presented with a skin lesion on his upper lip. The ulcer was originally thought to be due to a syphilitic infection, but later, after laboratory testing, was diagnosed as histoplasmosis, due to the fungus Histoplasma capsulatum. Skin lesions such as this can be a manifestation of “disseminated histoplasmosis”, referring to the spread of the fungal pathogen, H. capsulatum, throughout the body including the skin, bone marrow, brain and other organs. Disseminated histoplasmosis is most common amongst immunosuppressed people, such as those with AIDS.