An infection caused by the fungus Cryptococcus neoformans. The fungus enters and infects the body through the lungs. Cryptococcosis may go away on its own, remain in the lungs, or spread throughout the body (disseminate). Most cases of cryptococcosis are in people with weakened immune systems, such as people with HIV. In people with HIV, extrapulmonary (outside the lungs) cryptococcosis is an AIDS-defining condition.