Images of Memorable Cases: Case 17 Peripheral blood film from a 40-year-old, terminally ill woman with carcinoma of the cervix. 17. Disseminated histoplasmosis The leukocyte shown in the blood film contains yeast-phase organisms. Cultures of the blood and bone marrow grew Histoplasma capsulatum. Disseminated histoplasmosis typically occurs in immunodeficient patients, most commonly those with AIDS.