Among 272 cases of infection with Histoplasma capsulatum there were 108 suitable for special study because they were essentially untreated cases and because follow-up examinations were possible for a sufficiently long period after diagnosis. Neither the chronic pulmonary nor the disseminated types of case always gave positive serological results. The mortality among patients with the disseminated type (20 out of 24, or 83%) was higher than that among those with the chronic pulmonary type (27 out of 84, or 32%). Among the proved cases of chronic pulmonary histoplasmosis the underlying disease was serious and progressive, but there was in addition a high incidence of tuberculosis (25%). Since the prognosis of untreated histoplasmosis is so bad, the need for specific therapy is evident.
Course and Prognosis of Untreated HistoplasmosisA United States Public Health Service Cooperative Mycoses Study. JAMA. 1961;177(5):292–296. doi:10.1001/jama.1961.03040310010003