- Cryptococcus neoformans is an encapsulated yeast found widely in the environment but especially the feces of birds such as the pigeon. Inoculation occurs through inhalation of aerosolized yeast forms and does not spread from person-to-person.
- Although C. neoformans can infect immunocompentent individuals, this is rare and the vast majority of infections are in observed immunocompromised patients such as AIDS Patients who display reduced cell-mediated immunity. The primary manifestation of disease is a chronic meningitis notable for its slow onset. Patients gradually develop classic signs and symptoms of meningitis including fever, headache, neurological impairments, and meningismus. Disseminated disease may also occur and organisms can seed a wide variety of tissues; however, infection of the meninges is of primary concern.
- India Ink stain of CSF will reveal organisms whose capsules exclude the dye.