Definition of Cryptococcosis:

Cryptococcosis is infection with Cryptococcus neoformans fungus.

Causes, incidence, and risk factors:

Cryptococcus neoformans, the fungus that causes this disease, is ordinarily found in soil. It enters and infects the body through the lungs. Once inhaled, infection with cryptococcosis may go away on its own, remain in the lungs only, or spread throughout the body (disseminate).

Most cases are in people with a weakened immune system, such as those with HIV infection, taking high doses of corticosteroid medications, cancer chemotherapy, or who have Hodgkin's disease.

In people with a normal immune system, the lung (pulmonary) form of the infection may have no symptoms. In people with impaired immune systems, the cryptococcus organism may spread to the brain.

Neurological (brain) symptoms begin gradually. Most people with this infection have meningoencephalitis (swelling and irritation of the brain and spinal cord) when they are diagnosed.

Cryptococcus is one of the most common life-threatening fungal infections in people with AIDS.