"Cryptococcosis," is an infection that is caused when a person inhales the fungus, "Cryptococcus Neoformans." The disease most often affects people with AIDS. While it might be limited to a person's lungs, it frequently spreads throughout a person's body. Although nearly any organ in the body can become infected, the fungus is often times fatal if it infects a person's nervous system where it causes an inflammation of the membranes covering the spinal cord and brain - referred to as, "meningitis."
Cryptococcus is most often seen 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. The prevalence of cryptococcosis has been increasing over the past 20 years for many reasons, including the increase in incidence of AIDS and the expanded use of immunosuppressive drugs.
Dependent on the infectious syndrome, symptoms include fever, fatigue, chest pain, dry cough, swelling of abdomen, headache, blurred vision and confusion. Treatment options in non-AIDS patients who have reduced immune-system function is not well studied. Intravenous Amphotericin B combined with oral flucytosine may be effective. Every attempt should be made to reduce the amount of immunosuppressive medication until the infection is resolved.
The fungus that causes cryptococcis, 'C. neoformans,' is found around the world in soil that is contaminated with pigeon or other types of bird droppings. It has also been found on raw fruit that is unwashed. Cryptococcosis is fairly rare in people who are healthy, but is the most common fungal infection that affects people with AIDS. People with Hodgkin's disease, or who are taking large doses of medications that suppress the functioning of their immune system such as chemotherapy drugs or corticosteroids,' are also at increased risk of cryptococcal infection. Cryptococcosis is also referred to as:
Three things may happen after the cryptococcal fungus reaches a person's lungs. The person's immune system may heal their body without the need for medical intervention. The disease may remain localized in the person's lungs, or it might spread throughout the person's body. People who are healthy with average functioning immune systems find their bodies usually heal and the infected person does not notice any symptoms; they experience no complications.
The disease itself does not spread from one person to another. Cryptococcus is an opportunistic infection, one that places people with immune system diseases at a greater risk of developing more serious forms of the disease. In America, between 6 and 10% of all people with AIDS become infected with Cryptococcus.
If a person's body does not heal itself, the fungus starts to grow in their lungs and forms nodules that may be seen on chest x-rays. In the early stages of the infection a person commonly only exhibits symptoms of a respiratory infection such as a dry cough, so the disease is rarely diagnosed. The fungus does have the ability to remain dormant in a person's lungs and produce an active infection at a later time if the person's immune system is weakened.
If the disease becomes active it may cause cryptococcal pneumonia in the lungs. Sadly, cryptococcal pneumonia has symptoms that are similar to other pneumonias such as a cough, difficulties with breathing, and pain that can make it hard to accurately diagnose. The infection may spread to other parts of a person's body, the central nervous system and brain in particular.
Most people are not diagnosed with cryptococosis until they have presented with signs of cryptococcal meningitis, or infection of the membranes surrounding their spinal cord and brain. The symptoms gradually appear over a period of 2 to 4 weeks. Headache and a fever are the most common symptoms and occur in approximately 85% of those affected. Additional symptoms include:
A diagnosis is often times delays because the symptoms of classic meningitis, such as aversion to light and a stiff neck, do not happen in many people. In addition to meningitis, inflammation of a person's brain or, 'encephalitis,' and brain lesions called, 'tortulomas,' or, 'cryptococcomas,' may also develop. In addition to a person's brain, a cryptococcal infection may spread to:
An infected person may develop rashes or lesions that mimic other skin diseases such as, 'molluscum contagiousum,' preceding the development of cryptococcal meningitis. A small number of people with brain infections present with infections in other organs in their bodies as well.
Doctors who work on a regular basis with people who have AIDS have the most experience with diagnosing cryptococcosis. The doctors' preferred methods of diagnosis use simple and highly accurate blood and cerebrospinal fluid tests that detect the presence of an antigen produced by the fungus. The cerebrospinal fluid test is usually more sensitive to detecting the meningitis form of the infection. Cerebrospinal fluid is collected during a procedure referred to as a, 'lumbar puncture,' during which an anesthetic is applied to a small area of the person's back close to their spine and a needle is used to withdraw a sample of their cerebrospinal fluid from the space between their vertebrae and their spinal cord.
After the sample has been obtained, a small amount of ink called, 'India ink,' is added to it or a sample prepared from skin lesions. If the fungus is present it becomes visible when the ink binds to the covering or, 'capsule,' that surrounds the fungus. Quicker results are obtained with the India ink test, although it is less accurate than the blood test because some strains are not visible using this method. Antigen tests are routinely recommended for people who do not have symptoms yet have advanced AIDS.
Another way to achieve a diagnosis of cryptococcosis is to culture a sample of the person's sputum, tissue from a lung biopsy, or cerebrospinal fluid in the laboratory in order to isolate the fungus. Cultures are also done to assess the effectiveness of treatment. Chest x-rays are useful in assessing lung damage and might reveal a single mass or multiple distinct nodules, although an x-ray alone does not lead to a definitive diagnosis.
Upon achieving a diagnosis of cryptococcosis, treatment starts with amphotericin B or, 'Fungizone,' at times in combination with 5-flucytosine or, 'Ancobon.' Amphotericin B is a strong fungistatic medication with potentially toxic side effects such as kidney toxicity and lower concentrations of an important blood component called hemoglobin. The medication may also cause:
Treatment is usually provided intravenously during a stay in the hospital and continues until the person is stable or improving. 5-flucytosine is administered orally. People might also receive additional medication to minimize the side effects from these drugs.
Amphotericin B, either with or without 5-flucytosine, is administered for several weeks until the person is stable. After that the person receives oral fluconazole or, 'Diflucan.' Fluconazole is a broad-spectrum antifungal drug with few serious side effects. People with AIDS have to take fluconazole for the remainder of their lives to prevent a relapse of cryptococcosis. At times, fluconazole is given to people with advanced AIDS as a preventative measure.
Left untreated, cryptococcosis is always fatal. The acute mortality rate for people with AIDS is between 10 and 15%. The majority of deaths are attributable to cryptococcal meningitis and happen within two weeks after achieving a diagnosis. For people with AIDS who do not receive continued suppressive therapy, the relapse rate is between 50 and 60% within six months and a shortened life expectancy. After the cryptococcosis infection has been treated with success, people might be left with a number of neurological symptoms such as headache, weakness, hearing or visual loss. Fluid may also accumulate around the person's brain.
The best way to prevent cryptococcosis is to remain free of an HIV infection. People with suppressed immune systems should avoid areas that are contaminated with pigeon or other types of bird droppings.