Histoplasmosis is an infection caused by a fungus. The fungus lives in the eastern United States, particularly in the Ohio and Mississippi river valleys. It usually affects the lungs, but in more serious cases it affects other parts of the body as well.
You can get histoplasmosis by breathing the fungus into your lungs. The fungus is often spread by bird or bat droppings. You may be exposed to the fungus when:
The fungus is also found under bridges, along streams, and in caves.
Many times the symptoms of the infection are so mild that you don't even know you have it. If you do have symptoms, they may be like the symptoms you get when you have a cold or flu. Symptoms you may have are:
Your healthcare provider will ask about your symptoms. Tell your provider if you have lived, visited, or recently worked in the parts of the eastern US where histoplasmosis is common. Your provider will examine you and may order lab tests of your sputum, blood, skin, or urine.
You may not know you have had histoplasmosis until years later when, for some other reason, you may have a chest X-ray. The chest X-ray may show some scarring of your lungs from the infection.
Most of the time no special treatment is necessary because the body can fight the infection without any help.
If the infection is severe or your immune system isn't strong, your healthcare provider will prescribe an antifungal medicine. The medicines used most often are amphotericin B, itraconazole and ketoconazole. Depending on how severe your infection is, you may be treated first with IV (intravenous) medicine and then switched to capsules you take by mouth. You may need treatment for days, weeks or months, depending on how severe your illness is and how strong your immune system is.
Most people feel sick for just a couple of weeks and then get better without any long-term problems. However, histoplasmosis can be a serious disease if your immune system isn't working well. It is serious, for example, if you have AIDS, take high doses of steroids for other medical problems, or are being treated for cancer. In these cases the disease may cause pneumonia or spread from the lungs to other parts of the body, such as the brain, stomach, intestines, skin, or adrenal glands. It is rare for histoplasmosis to spread like this but when it does, it can be fatal.
If you live in a region of the eastern US where histoplasmosis is common, you can help prevent infection by wearing a mask or respirator when you work in a dirty or dusty area. For example, you should take this precaution if you are collecting soil samples, remodeling or demolishing old buildings, cleaning chicken coops, cutting trees, or going into caves. If your immune system is weak, it is especially important to try to avoid places where you might be exposed to the fungus and to wear a mask when you risk exposure.
Unlike infections such as colds or flu, histoplasmosis isn't spread from person to person by coughing, so you don't have to worry about infecting other people.
