[1] This species is a close relative of Histoplasma capsulatum, the agent of classical histoplasmosis, and the two occur in similar habitats.

[1] Histoplasma duboisii is restricted to continental Africa and Madagascar, although scattered reports have arisen from other places usually in individuals with an African travel history.

[4] These early reports implicated strains that produced larger yeast cell forms than H. capsulatum,[2] and the Irish mycologist James Thompson Duncan suggested they might represent a distinct taxon.

[6] Five years after its description, Professor Edouard Drouhet of the Pasteur Institute in Paris reduced the taxon to synonymy with H. capsulatum, designating it as a variant.

[2][12] The yeast form of H. duboisii are oval in shape with thick cell walls[1] composed of galactomannan intermixed with β-(1,4)-glucan.

[14] The identity of H. duboisii can be ascertained by conventional laboratory methods involving mycelial-to-yeast conversion on brain-heart infusion medium supplemented with sheep blood and either glutamine or cysteine, and microscopic verification of the size of yeast cells.

[14][15] Unlike H. capsulatum, H. duboisii lacks the ability to produce the enzyme urease, and this feature can be used for confirmatory identification.

[11] The species is the etiological agent of African histoplamosis, and is endemic throughout western and central Africa[1] in addition to Madagascar.

[11] Unlike classical histoplasmosis, infections caused by H. duboisii are often restricted to the skin or subcutaneous layer occasionally involving bone.

[11] Subcutaneous lesions are warm, firm and tender, sometimes rupturing to release a yellowish discharge containing the fungus prior to evolving into cold abscesses.

[14] Disseminated disease is especially common in immunocompromised individuals, and can involve any organs but infection of the heart and central nervous system are rare.

The afflicted individual resided in Kerala, an area with an abundant bat populations and a climate similar to that of endemic countries.

[3] The fungus is thought to enter the body mainly by inhalation of airborne microconidia or fragments of vegetative hyphae[14][18] although transcutaneous infection has been reported.

[1] Even though HAART has greatly improved the prognosis of HIV disease, the risk of immune reconstitution inflammatory syndrome (IRIS) is known in patients with African histoplasmosis.

[13] Secondary infections of the skin, subcutaneous tissues and the lymph nodes in the form of small papules and ulcerative granulomas have been reported in absence of involvement of the lungs and internal viscera.

[13] Animal studies have found the virulence of H. duboisii to be lower than that of H. capsulatum, which is consistent with the tendency of the former to form mainly localized cutaneous and subcutaneous infections.