Cryptococcosis is an infectious fungal disease that is also known as Busse-Buschke disease. The fungal pathogen exploits a weakened immune system and can then spread to various organs. The disease is then life-threatening. People with a healthy immune system are not usually at risk.
Here you will find further information and selected specialists for the diagnosis and treatment of cryptococcosis.
Cryptococcosis is a serious fungal infection of the lungs. If it is not treated in time, it has a poor prognosis and is often fatal.
Cryptococcosis was first described in 1894 by
described. In the past, cryptococcosis was also known as "European blastomycosis".
Cryptococcosis is usually triggered by the fungus Cryptococcus neoformans. It belongs to the so-called encapsulated yeasts and requires a weakened immune system or other previous illnesses. It is referred to as a facultative pathogen.
Healthy people with an intact immune system usually do not suffer much from cryptococcosis. The body can usually fight the fungal pathogens well.
In HIV-infected people, however, the pathogen can multiply well. Cryptococcosis can then spread to other organs. The central nervous system in particular is affected by cryptococcosis in HIV-infected people.
There is no obligation to report fungal infections, including cryptococcosis. However, it is desirable to report the occurrence of the disease to the Robert Koch Institute.
Cryptococcosis occurs worldwide. However, it is much more common in the USA and South East Asia than in Europe.
The mortality rate among HIV patients is around 20 percent. In total, over 600,000 people die of cryptococcosis every year.
Almost one million people infected with HIV contract cryptococcal meningoencephalitis, which is caused by cryptococcosis, every year. Meningoencephalitis is an inflammation of the brain and meninges.
Animals can also become infected with cryptococcosis, including cats. In animals, however, the disease has less of an effect on the lungs, nervous system and skin. Instead, it usually
Tumor-like growths can also occur on the face and skull bones. As a result, cryptococcosis is also life-threatening for the pet.
In Europe, cryptococcosis is usually caused by the yeast Cryptococcus neoformans. The pathogen Cryptococcus gattii causes cryptococcosis much more rarely. This fungus is a variation of Cryptococcus neoformans.
There are a further 30 subspecies of the fungus genus Cryptococcus. However, only a few of these appear to be able to trigger cryptococcosis.
As a rule, several weeks elapse between the time of infection and the outbreak of cryptococcosis.
Cryptococcus neoformans reproduces by sprouting. This means that a daughter cell grows out of the mother cell, which is around 2 to 8 µm in size. This yeast belongs to the genus Basidiomycota. Baker's yeast, which is also a yeast fungus, belongs to the tube fungi.
Cryptococcus neoformans is usually found in the soil and on grass and cereal stalks. It can also be found in bird droppings. When this decomposes into dust, it is released into the air and a host can inhale the pathogen. The fungus is very resistant to heat and dehydration.
Cryptococcus neoformans is so dangerous because it has developed strategies against our immune defenses. The fungus is surrounded by a polysaccharide capsule. This prevents the immune system's phagocytes from absorbing the fungus and thus destroying it. The fungus has also stored melanin in its cell walls. This also makes it resistant to the immune system's defense cells.
The resistance of the fungal pathogen can often cause cryptococcosis.
Cryptococcus neoformans can multiply very well in the intestines of birds. Humans inhale the pathogens by stirring up the bird droppings. This allows them to enter the respiratory tract and lungs. This is where cryptococcosis develops.
Bird droppings often contain the fungal pathogen Cryptococcus neoformans © Nutlegal | AdobeStock
In very rare cases, transmission via the bloodstream after an injury is also possible. Infection from person to person is almost impossible. Pets, especially cats, can also be affected by cryptococcosis. However, transmission from animals to humans has never been observed to date.
Starting from the lungs, the pathogens reach other organs via the bloodstream. This is known as hematogenous distribution. The infection can be life-threatening for people with a weak immune system. These include
Fatal lesions can occur in the brain in particular. Harmful granulomas often develop as a result of cryptococcosis. The result is life-threatening meningoencephalitis.
The symptoms are often non-specific. Cryptococcosis often causes
The haematogenous spread of the pathogen can lead to impairments almost anywhere in the body:
There is a risk of
Very often, uncharacteristic skin changes also occur as a manifestation of cryptococcosis. If cryptococcosis is caused by an injury to the skin, the infestation can also remain localized.
The diagnosis begins with a patient interview, the anamnesis. The doctor reconstructs the course of a possible infection. This is followed by a physical examination. This includes
If cryptococcosis is suspected, the lungs and central nervous system are thoroughly examined. Common imaging procedures are used, such as
A cerebrospinal fluid puncture is then the most important diagnostic measure for detecting cryptococcosis. This is the removal of cerebrospinal fluid (nerve fluid) from the spinal cord and its subsequent examination. A negative image is taken using an ink preparation.
In the vast majority of cases, examination of the cerebrospinal fluid can confirm the diagnosis of cryptococcosis.
If only a localized area of the skin is affected, the examination is initially limited to a biopsy in order to be able to diagnose cryptococcosis unequivocally.
As cryptococcosis can be fatal, rapid treatment is life-saving. Treatment takes place as an inpatient, i.e. in hospital.
The treatment of cryptococcosis depends primarily on the symptoms and the site of manifestation of the disease. First and foremost, antimycotics (antifungal agents) are used for treatment.
If meningitis has already occurred, a combination of several antimycotics is usually necessary. The patient is usually given the antimycotics
The success of the therapy is monitored clinically and observed by means of regular lumbar punctures. During the lumbar puncture, cerebrospinal fluid is taken for examination. If the cerebrospinal fluid is free of pathogens after one month at the earliest, the patient can be switched to secondary prophylaxis.
Cryptococcosis can increase intracranial pressure. In this case, brain drainage is necessary.
The aim of therapy is to establish a sufficient immune constitution. Once this has been achieved, the patient can end the therapy - at the earliest after six months.
People suffering from AIDS are normally given the drug fluconazole. It is used for long-term prophylaxis against cryptococcosis.
Otherwise, it is almost impossible to protect yourself against the disease, as the fungal pathogens are airborne. Birds whose droppings often contain fungal pathogens are everywhere. If there is a plague of pigeons, this can be combated to prevent cryptococcosis.
People with a weakened immune system should strengthen their defenses through
strengthen their immune system.
