Cryptococcosis pathology

Cryptococcosis is a systemic disease caused by the yeast fungus Cryptococcus neoformans. Is a encapsulated yeast that has five serotypes, A, B, C, D and AD, of two varieties called neoformans (A, D and AD) and gatii (B and C). The latter is more predominant in Australasia

Histology from cryptococcosis

Yeast forms of cryptococcosis are generally surrounded by massive gelatinous edema (figure 1, arrow). The around inflammatory the reaction depends on the stage of the clinic injury and on the immune status of the patient. Immunocompetent patients can cause rapid granulomatous answer in which the organisms can be difficult to see without special stains, while immunocompromised patients show minimal inflammation and edema around the numerous forms of yeast as seen in the case illustrated here (Figure 2). The yeast forms of cryptococcosis are often widely separated by their thick mucoid capsules. The PAS stain decorates the yeast (Figure 3) and the mucicarmine stain decorates the highly characteristic gelatinous capsule of a bright pink (Figure 4).

Special spots for cryptococcosis.

The cryptococcus capsule is heavily stained with the mucicarmine stain (Figure 4). Grocott, mucicarmine, methanamine silver, toluidine blue or methylene blue are sometimes required to help illustrate the characteristic budding yeasts. This is especially useful in immunocompetent Hosts with a rapid inflammatory response

Differential diagnosis from cryptococcosis pathology

Histoplasmosis and blastomycosis: the positivity of mucicarmine discriminates cryptococcus from these other organisms. The situation can be complicated by the rare cryptococcal strain that lacks a capsule. In case of cryptococcal doubt antigens can be identified with the latex agglutination of in the place Hybridization can be used.