Histoplasmosis Definition and Meaning

Histoplasmosis is an infection with the mold Histoplasma capsulatum, which can affect the entire body but is usually limited to the lungs. This disease is rare in Europe. Areas of distribution are especially Africa, Indonesia, South, Central and partly North America.

What is histoplasmosis?

According to abbreviationfinder, the causative agent of histoplasmosis is a dimorphic fungus called Histoplasma capsulatum. Dimorph means that it can exist both in the mycelial form as mold and in the form of single cells as yeast.

Its appearance depends on the temperature. The mold form is at 25 degrees and the yeast form is at 37 degrees (body temperature). Anyone exposed to this fungus can develop histoplasmosis, although people with a healthy immune system usually do not develop any symptoms.

Only in immunocompromised people, e.g. B. in AIDS, the pathogen often spreads over the entire body with often fatal course of the disease. In the distribution areas of this fungus, histoplasmosis is considered a defining symptom of HIV.


Histoplasmosis is caused by infection with the fungus Histoplasma capsulatum. Infection often takes place in bat caves or chicken coops.

It is transmitted by dust and settles in the lungs. The so-called macrophages (scavenger cells) immediately become active and enclose the fungal cell. However, the fungus is not killed in this phase. On the contrary, it can continue to multiply within the scavenger cells by sprouting. Since it appears as a single cell at body temperature as a yeast fungus, it can get into the entire body with the macrophages via the bloodstream.

In people with an intact immune system, the pathogens are killed in a further phase of the immune reaction. In over 90 percent of cases, there are no symptoms and lifelong immune protection against Histoplasma capsulatum is built up. Immunocompromised people, on the other hand, often develop serious illnesses with histoplasmosis, sometimes with a fatal outcome.

Symptoms, Ailments & Signs

In about 90 percent of cases, infection with Histoplasma capsulatum causes no symptoms. In individual cases, small scars in the area of ​​the lungs can be detected during the X-ray examination. Symptomatic patients suffer from ailments such as a dry cough, weakness and common cold symptoms. Severe stomach pains with vomiting can also occur.

In the course of the disease, fever and chills also occur, combined with sweat attacks and severe stomach pain. The first symptoms usually appear within 3 to 14 days after contact with the fungus. If histoplasmosis progresses, weight loss can occur.

In addition, symptoms such as weakness, shortness of breath and pain in the chest may occur. If the eyes are involved, visual disturbances occur. A severe course is expressed by patchy areas in the lower part of the lungs. Other symptoms may occur in people with a weakened immune system.

Corresponding risk groups suffer from headaches, cramps and injuries in the oral cavity in addition to the histoplasmosis symptoms. In the absence of or insufficient treatment, infection with Histplasma capsulatum can lead to the death of the patient. Depending on the form of the disease, other symptoms of the brain, nervous system or skin may appear.

Diagnosis & History

Due to the rarity of histoplasmosis in Europe, misdiagnosis is common. Although the disease is usually silent, it can lead to severe symptoms in the event of an infection with a high concentration of fungal spores or in the case of an immune deficiency, which manifests itself as pain when breathing in, fever, chills and coughing.

There may also be coughing up blood, wart-like lumps on the skin, and swollen lymph nodes. A suspected diagnosis is made by examining the circumstances of the disease and diagnoses by exclusion of other diseases. If the suspicion of histoplasmosis is confirmed, the fungus Histoplasma capsulatum can be detected by skin swabs, biopsy of the lungs and blood or spinal cord tests.

Imaging techniques show shadows on the lungs created by calcified nodules. Antibody detection is usually unreliable in histoplasmosis, because particularly immunocompromised people do not show adequate immune reactions.


Histoplasmosis causes severe symptoms and complications in the lungs and airways. In most cases, the person affected initially feels ill and exhausted and suffers from a high fever. There is also pneumonia and a dry cough. Coughing can also develop into coughing up blood, which usually leads to anxiety or panic attacks.

The patient’s immune system is severely weakened and further infection or inflammation may occur. The usual symptoms of influenza also appear, so that the patient’s resilience drops extremely. It also leads to underweight and in many cases to dehydration. The quality of life of the patient is greatly reduced and limited by the histoplasmosis.

Direct treatment is not necessary in every case. The histoplasmosis often heals on its own and there are no further complications. If the patient has previously suffered from a weakened immune system, the treatment is carried out with the help of medication. If left untreated, histoplasmosis can, in the worst case, lead to death if the person affected also has HIV, for example.

When should you go to the doctor?

If the affected person suffers from impaired breathing, a doctor should be consulted. If there are no other colds or allergic reactions, breathing restrictions are considered alarming and must be clarified. The organism is undersupplied, which leads to a life-threatening condition in the long term. In case of inner restlessness, a feeling of illness or a general weakness, a doctor should be consulted.

Tiredness, exhaustion and a drop in the usual performance are signs that must be thoroughly examined and treated. If the symptoms increase or spread further in the body, a doctor’s visit is essential. If the person concerned suffers from pain when inhaling, special caution is required. If you see this warning, you should see a doctor as soon as possible so that no further damage occurs. Sleep disorders, tachycardia, high blood pressure and abnormal heart rhythms must be examined by a doctor.

Swollen lymph nodes that are not related to the flu are considered unusual, especially if they have been present for several weeks. Signs such as chills and severe unwanted weight loss also require a doctor’s visit. A slow increase in the symptoms described are indications of the fungal disease. The sufferer experiences a gradual deterioration in their well-being and should see a doctor as soon as the changes interfere with their daily activities.

Treatment & Therapy

Therapy for histoplasmosis is usually not necessary due to the minor symptoms. In people with an intact immune system, acute symptoms can also occur as a result of an infection with a high concentration of pathogens, but the disease heals completely after seven to eighteen days.

Immunocompromised people, on the other hand, often develop the chronic form of histoplasmosis, in which case the pathogens are not completely destroyed. The chronic histoplasmosis can then progress to the disseminated form with serious symptoms which, if left untreated, result in over 90 percent death. However, if disseminated histoplasmosis is treated, the lives of over 85 percent of patients can be saved.

In the case of a chronic or disseminated course of the disease, it is essential to treat it with medication for several weeks with antimycotics (fungus-fighting agents). If foci of pus have formed in the body, its surgical removal is indicated. Persons with a chronically weakened immune system (HIV) must be permanently treated with antimycotics for histoplasmosis.

Outlook & Forecast

The prognosis for histoplasmosis is linked to the general health of the patient. With a stable and healthy immune system, the prognosis is favorable. The pathogens can be killed by the body’s own defense system. This prevents the fungus from spreading and the fungal spores are removed from the organism via the natural human excretion system. In addition, the body develops an immunity to the pathogens, so that the affected person is adequately protected from renewed infestation of the fungal spores for life.

People who have a weakened immune system can expect a worse prognosis in most cases. The risk group includes infants, children, the elderly or the chronically ill. Their body’s defense system is not yet fully developed or is not functional due to other disorders. This means that the pathogens can be killed more difficult or not at all. In addition, they can multiply and spread further without any significant resistance.

If there is no comprehensive medical care, the general state of health of the person affected deteriorates within a short time. In addition, other diseases can develop, since the organism is fundamentally susceptible to germs, bacteria or other fungi. The prospect of a cure for these people depends on the progression of the disease and the possibility of adequately supporting the immune system.


To prevent histoplasmosis in a risk area, e.g. B. Wear a face mask when visiting a bat cave. People with a weakened immune system can inhale antifungal drugs prophylactically or take certain antibiotics. Even healthy people who have already built up immunity to histoplasmosis should not expose themselves to the pathogens in massive form.


In most cases, those affected by histoplasmosis do not have any special and direct options and measures for aftercare. This disease must first and foremost be examined and treated by a doctor so that there are no further complications or a further deterioration of the symptoms. Histoplasmosis can only be treated by early detection of the symptoms.

The disease can be fatal if left untreated. In most cases, drugs are used to treat the histoplasmosis. It is important to ensure that the medication is taken regularly and, above all, correctly. If anything is unclear or if you have any questions, you should always consult a doctor first.

Possible interactions or side effects of the medication must also be taken into account. The lungs must also be spared in the case of histoplasmosis. Efforts or stressful and physical activities should be avoided in order not to unnecessarily burden the lungs.

Smoking should also be avoided, although a healthy lifestyle can generally have a very positive effect on the further course of this disease. Contact with other people affected by histoplasmosis can also be useful, since information is rarely exchanged.

You can do that yourself

Histoplasmosis can be avoided by strict hygiene measures. If the person concerned is in a risk area, a face mask must be worn, for example. In general, the disease can be avoided by avoiding exposure to the causative agent of histoplasmosis.

If the patient suffers from a weakened immune system , antibiotics can be taken as a precaution to prevent the disease from breaking out. In the case of a serious illness, however, treatment by a doctor is always necessary, since the illness can otherwise lead to the death of the patient. Patients must take care of their bodies during treatment and not expose them to unnecessary stress. Bed rest is recommended, with the person being cared for by friends or family. In the case of pneumonia, various home remedies such as tea or milk with honey can be used to protect the throat and counteract the cough.

In the case of panic attacks or anxiety states, a discussion with a doctor should always be sought. As a rule, the doctor can calm the patient down and explain the consequences of the disease. Talking to other histoplasmosis patients can also have a positive effect on the disease.


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