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(European Blastomycosis; Torulosis)


Sanjay G. Revankar

, MD, Wayne State University School of Medicine

Last full review/revision Sep 2019| Content last modified Sep 2019
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Cryptococcosis is infection caused by fungus Cryptococcus neoformans or Cryptococcus gattii.

  • People may have no symptoms or may have headache and confusion, a cough and an achy chest, or a rash, depending on where the infection is.

  • The diagnosis is based on culture and examination of tissue and fluid samples.

  • Antifungal drugs are given by mouth or, if the infection is severe, intravenously.

Cryptococcus neoformans occurs primarily in soil that is contaminated with bird droppings, particularly those of pigeons. Cryptococcus gattii usually is present in the soil around trees. Unlike Cryptococcus neoformans, Cryptococcus gattii is not associated with birds.

Cryptococcus is present around the world, but infection was relatively rare until the AIDS epidemic began. Cryptococcosis is the most common potentially fatal fungal infection in people with AIDS.

The fungus tends to infect people who have a weakened immune system, including those with the following:

However, cryptococcosis caused by Cryptococcus gattii can also develop in people with a normal immune system.

Infection usually occurs when people inhale the spores of the fungus. Thus, cryptococcosis typically affects the lungs. It most commonly spreads to the brain and tissues covering the brain and spinal cord (meninges), resulting in meningitis.

Cryptococcosis may also spread to the skin and other tissues, such as the bones, joints, liver, spleen, kidneys, and prostate. Except for skin infections, these infections usually cause few or no symptoms.


Cryptococcosis usually causes mild and vague symptoms. Other symptoms vary depending on where the infection is:

  • Lung infection: No symptoms in some people, a cough or an aching chest in others, and, if the infection is severe, difficulty breathing

  • Meningitis: Headache, blurred vision, depression, agitation, and confusion

  • Skin infection: A rash, consisting of bumps (sometimes filled with pus) or open sores

Lung infection is rarely dangerous. Meningitis is life threatening.


  • Culture and examination of a sample of tissue or fluid

To diagnose cryptococcosis, a doctor takes samples of tissue and body fluids to be cultured and examined. A spinal tap (lumbar puncture) is done to obtain cerebrospinal fluid (the fluid that surrounds the brain and spinal cord).

Blood and cerebrospinal fluid may be tested for certain substances released by Cryptococcus.

Doctors may also take a x-ray to check for signs of infection in the lungs.


  • Antifungal drugs

Antifungal drugs are usually used to treat cryptococcosis.

People with a normal immune system

If the infection affects only a small part of lung and does not cause any symptoms, usually no treatment is needed. However, some doctors prefer to always treat cryptococcosis. Fluconazole is given by mouth to shorten the duration of the illness and reduce the risk of the infection spreading.

If a lung infection causes symptoms, fluconazole is given by mouth for 6 to 12 months.

For meningitis, treatment is amphotericin B, given intravenously, plus flucytosine, given by mouth, followed by fluconazole, given by mouth, for many months.

For a skin infection, people are usually given fluconazole by mouth or, if the infection is severe, amphotericin B intravenously.

People with a weakened immune system

People with a weakened immune system always require treatment.

Mild to moderate lung infection may be treated with fluconazole given by mouth for 6 to 12 months.

Severe lung infection or meningitis may be treated with amphotericin B, given intravenously, plus flucytosine, followed by fluconazole, both given by mouth.

After cryptococcosis is treated, people with AIDS usually need to continue taking an antifungal drug (such as fluconazole) until AIDS is controlled and they have taken antifungal drugs for at least a year. AIDS is considered controlled when the CD4 count (the number of one type of white blood cell) increases to a certain level and the amount of HIV in the blood (called viral load) has been very low or undetectable for at least 3 months.

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