Histoplasmosis is a kind of fungal infection usually developed in immunocompromised individuals. Initially, the causal organism, Histoplasma capsulatum, infects the lungs, developing pulmonary histoplasmosis. If not treated well within time, the disease may spread into other parts of the body as well. The disease may progress to either disseminated or chronic forms involving internal organs like adrenal glands, liver, spleen, lymph nodes, bone marrow, skin and mucous membranes, and the brain. The real paradox of the disease is that, in most of the cases, the disease is still being misdiagnosed as tuberculosis globally due to the radiological resemblances and the limited availability of rapid diagnostic tools. The physicians are unaware of the disease as it is not very much familiar amongst them. The present paper deals with the study of histoplasmosis, its epidemiology, discovery, clinical symptoms, oral manifestations, diagnosis, histopathology, methotrexate therapy and the development of facial/cutaneous histoplasmosis, and the histo- plasmosis masquerading as cancer in the light of recent researches done so far in the field of emergency medicine and critical care.

Keywords: Histoplasmosis; Histoplasma capsulatum; Pulmonary and Disseminated Histoplasmosis; Oral Manifestations; Methotrex- ate; Histoplasmosis and Cancer

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