What is Cryptococcus?
Cryptococcus is a type of fungus that is found in the soil worldwide,
usually in association with bird droppings. The major species of Cryptococcus
that causes illness in human is Cryptococcus neoformans. Another less common
species that can also cause disease in humans, Cryptococcus gattii, has been
isolated from eucalyptus trees in tropical and sub-tropical regions. Since 1999,
C. gattii has also been found in regions of the Pacific Northwest, particularly
Victoria Island in British Columbia, and Oregon and Washington in the United
States.
Who gets cryptococcosis?
Cryptococcosis is disease due to a species of the fungus Cryptococcus.
C.
neoformans typically infects immunocompromised persons. Most people in the
United States who develop cryptococcal infections are HIV-positive. However,
occasionally persons with no apparent immune system problems develop
cryptococcosis. Infections with C. gattii have also occurred in healthy persons
without compromised immune systems.
How is Cryptococcus spread?
Inhalation of airborne fungi. Cryptococcosis is not known to be spread from
person to person.
What are the symptoms of a cryptococcal infection?
Cryptococcal infection may cause a pneumonia-like illness, with shortness of
breath, coughing and fever. Skin lesions may also occur. Another common form of
cryptococcosis is central nervous system infection, such as meningoencephalitis.
People with cryptococcal meningoencephalitis are usually immunocompromised.
Symptoms may include fever, headache, or change in mental status.
How soon do symptoms appear?
Incubation times vary for infection due to Cryptococcus species. Symptoms
from C. gattii infection are estimated to begin anywhere from 2-11 months after
exposure. The incubation time for C. neoformans is not known.
If I have symptoms, should I see my doctor?
Yes, it is very important to seek immediate medical evaluation.
How is a cryptococcal infection diagnosed?
The diagnosis can be made by microscopic examination and/or culture of tissue
or body fluids such as blood, cerebrospinal fluid and sputum. The cryptococcal
antigen test is a rapid test that can be performed on blood and/or on
cerebrospinal fluid to make the diagnosis.
How are cryptococcal infections treated?
Treatment of meningoencephalitis and other severe infections is usually
initiated with an amphotericin B formulation, with or without flucytosine.
Fluconazole is used for maintenance therapy in HIV-infected patients with
cryptococcal meningoencephalitis, and may be used for patients with milder forms
of infection not involving the central nervous system.
How can cryptococcal infections be prevented?
C. neoformans is commonly spread by bird droppings, especially pigeon
droppings. People who have weakened immune systems should avoid areas
contaminated by bird droppings, and should avoid contact with birds. There are
no formal recommendations for the prevention of C. gattii infection.