Cryptococcus causes mainly central nervous system, pulmonary and cutaneous lesions, which can be life-threatening in severe cases. Disseminated lesions can also occur in the ends of long bones, joints, liver, spleen, kidneys, heart, testes, prostate, and other organs. Typically, affected tissues contain peptide-like yeast cysts, which are formed by the accumulation of polysaccharides in the cryptococcal cyst membrane, but have only mild or no acute inflammatory changes. In severe cases, sepsis may occur and spread to all organs of the body or even cause death. What is the pathogenesis of cryptococcal capsular polysaccharide accumulation? Let’s take a look below. Cryptococcus, which exists in soil and pigeon droppings, can be inhaled into the respiratory tract along with dust. Dry cryptococci are only 1 μm in diameter and can enter the alveoli. Cryptococcus is not wrapped in pods outside the body, and soon after entering the body, it forms pods with pods that are pathogenic. Cryptococci that invade the body do not necessarily cause disease, and cellular immunity plays a major role in preventing cryptococcal infection. After cryptococci invade the lungs, a few form granulomas and develop symptoms. Cryptococcus can enter the central nervous system from the lungs via the blood. The reasons why the bacterium often invades the CNS may be: 1) lack of antibodies in the cerebrospinal fluid; 2) lack of complement activation system in the cerebrospinal fluid; 3) dopamine in the cerebrospinal fluid favors the growth of cryptococci. Cryptococcal meningitis is more significant for soft meningeal lesions at the base of the skull. There is extensive accumulation of exudate in the subarachnoid space containing monocytes, lymphocytes, and cryptococci. Restricted granulomas may also form, the latter being a more reactive manifestation of the organism and consisting of histiocytes, giant cells, lymphocytes, and fibroblasts; cryptococci are less commonly found, mostly within giant cells and histiocytes. The pathogenic bacteria can also invade the brain parenchyma along the perivascular sheath, causing vasculitis in the brainstem, resulting in localized brain tissue ischemia and softening, and granulomas can be formed in the brain parenchyma. Cryptococcus can also proliferate in the perivascular space and form many cysts in the gray matter, which are filled with Cryptococcus. There are two types of cutaneous lesions: granulomas and glial lesions, the latter having less tissue reaction and containing large numbers of cryptococci.