[6] Although Lutz did not suggest a name for the disease caused by this fungus, he made note of structures he called "pseudococcidica" together with mycelium in cultures grown at 25 °C.

[6] Finally in 1930, Floriano de Almeida created the genus Paracoccidioides to accommodate the species, noting its distinction from Coccidioides immitis.

[8] In tissue, budding occurs inside the granulomatous center of the disease lesion, as visualized by hematoxylin and eosin (H&E) staining of histologic sections.

[10] In electron microscopy, cells with multiple buds have been found to have peripherally located nuclei and cytoplasm surrounding a large central vacuole.

[12] In the tissue form of P. brasiliensis, yeast cells are larger with thinner walls and a narrower bud base than those of the related dimorphic fungus, Blastomyces dermatitidis.

[19] However, the precise ecology regularities of the fungus remain elusive, and P. brasiliensis has rarely been encountered in nature outside the human host.

[24] Paracoccidioides brasiliensis causes a disease known as paracoccidioidomycosis characterized by slow, progressive granulomatous changes in the head mucosa, notably the nose and sinuses or the skin.

[10] Due to the high proportion of cases affecting the oral mucosa, these tissues were originally thought to be the primary route of entry of fungus.

[3] However, strong evidence now indicates the respiratory tract is the chief point of entry[10] and P. brasiliensis lung lesions occur in nearly a third of progressive cases.

[10][26] The hormone estrogen is thought to inhibit the transformation of the mycelial to the yeast form, as supported by in vitro experimental data, and this factor may account for the relative resistance of women to infection.

[10][28] A study reported detection of 43 kD antigen in pooled sera of affected individuals, which might provide a basis for the development of a diagnostic test.

[33] The typically extensive involvement of lymphoid tissue and the limited occurrence of the gastrointestinal tract, bone and prostate set the clinical picture of paracoccidioidomycosis apart from that of blastomycosis.