Coccidiomycosis, a systemic mycosis, in a 20 year old male initially suspected of having Hodgkin's disease. A small upper mediastinal mass was identified on a routine chest X-ray. Coccidioides immitis is endemic in the southwest United States and parts of Mexico, Central and South America. Inhalation of Coccidioides immitis arthroconidia, carried by dust storms, causes pulmonary infection. Photograph courtesy of Jack Saiki, M.D., University of New Mexico Department of Medicine.