Histoplasmosis is an infection caused by a fungus, called Histoplasma capsulatum (H. capsulatum). The fungus lives in the soil, and is breathed in through a person’s lungs. Most people with histoplasmosis have no symptoms and may never know they are infected. A small number of people may develop flu-like symptoms that last about 10 days. But histoplasmosis can be serious for people with weakened immune systems or who have chronic diseases, or for infants. Rarely, it can lead to death.
Because the symptoms are alike, doctors sometimes mistake histoplasmosis for tuberculosis. About 500,000 people are exposed to H. capsulatum each year in the United States.
Signs and Symptoms
Most people with histoplasmosis have no symptoms or very mild ones. Signs and symptoms that happen in rare cases include the following:
- Sudden, flu-like infection -- includes fever, chills, cough, chest pain, and headache
- Long-term lung infection -- develops slowly over weeks to months and produces a cough that gets worse, weight loss, night sweats, and sometimes shortness of breath
- Trouble breathing -- this can happen to people who breathe in very large amounts of the fungus. It is sometimes called "spelunker's lung" because it can happen after exploring caves.
When the disease spreads throughout the body, it affects many organ systems. A person may have the following symptoms:
- Meningitis (inflammation of the membranes of the brain and spinal cord)
- Ulcers in the mouth
- Infection of heart valves
- Enlarged liver and spleen
- Swollen lymph nodes
Histoplasmosis is caused by a common fungus that is found in mild climates throughout the world. Many people living in the Ohio and Mississippi river valleys of the United States have been infected with the fungus, called H. capsulatum. It grows in moist soil that is rich in nitrogen, or in places contaminated with bird or bat droppings, such as attics, barns, caves, and city parks.
People breathe the spores of fungus into the lungs, where they grow. In people with healthy immune systems, they usually do not spread to other parts of the body. In those with weakened immune systems, however, the spores may spread to the lymph nodes, liver, spleen, bone marrow, adrenal glands, and digestive system.
Histoplasmosis may also occur in the wake of a solid organ transplant, such as a heart, lung, or kidney transplant.
Many people living in mild climates can become infected with histoplasmosis. Those most at risk of becoming infected include:
- Farmers and poultry farmers
- Construction workers
- Spelunkers (cave explorers)
- Geologists and archeologists
- Landscapers and gardeners
- People who have contact with bats
Those at risk of severe infection include:
- People with weakened immune systems (from HIV, corticosteroid therapy, organ transplantation, and chemotherapy)
- Very young children
- Senior adults
- People with chronic diseases, such as lung disease
Because most people with histoplasmosis have no symptoms, it can be hard to diagnose. In addition to a physical exam, your doctor may do the following tests:
- Fungal culture -- can take several weeks to confirm diagnosis, so this test is not used if someone needs immediate treatment
- Fungal stain or blood test
- Chest x-ray or computerized tomography (CT) scan
It isn’t easy to prevent exposure to the fungus that causes histoplasmosis because it is widespread. However, the following steps may help prevent infection:
- Wear masks or respirators when in places contaminated by bird or bat droppings
- Spray contaminated areas with water, which helps keep the spores from being released
Mild cases of histoplasmosis may not need to be treated. Doctors treat more serious cases, with symptoms that include high fever, trouble breathing, loss of appetite, and malaise, with antifungal medications.
Medications stop the fungus from growing in the body. Doctors often use these medications in severe cases when the infection has spread to other organs and tissues throughout the body.
- Amphotericin B (Fungizone IV, Abelcet) -- given intravenously (IV). Your doctor may start with this drug, then switch to itraconazole.
- Itraconazole (Sporanox) -- taken by mouth
Surgery and Other Procedures
Surgery is only needed in rare cases when serious complications arise.
Nutrition and Dietary Supplements
Although no supplements cure histoplasmosis, a few studies suggest that some supplements may help reduce symptoms. Ask your doctor about the best ways to add complementary therapies into your overall treatment plan. Always tell your health care provider about the herbs and supplements you are using or considering using.
Following these nutritional tips may help reduce symptoms:
- Eat bitter and spicy foods, such as those containing turmeric (curries), cayenne peppers, green chilies, olives, figs, garlic, and ginger.
- Drink warm teas which contain spices, such as cardamom, clove, and cinnamon.
- Eat antioxidant foods, including fruits (such as blueberries, cherries, and tomatoes) and vegetables (such as squash and bell peppers).
- Drink 6 to 8 glasses of filtered water daily.
The following supplements may help reduce symptoms, although there isn’t any scientific evidence to know for sure:
- Vitamin C, 500 to 1,000 mg, 1 to 3 times daily. Vitamin C is an antioxidant and may help strengthen the immune system.
- Grapefruit seed extract (Citrus paradisi), 100 mg capsule or 5 to 10 drops (in favorite beverage) three times daily when needed. Grapefruit seed may have antibacterial, antifungal, and antiviral properties. It may also help strengthen the immune system. Grapefruit seed extract interacts with a number of common medications, so don’t take it without asking your doctor first.
- Probiotic supplement (containing Lactobacillus acidophilus), 5 to 10 billion CFUs (colony forming units) a day, when needed for maintenance of gastrointestinal and immune health. You should refrigerate your probiotic supplements for best results. People with autoimmune conditions, such as lupus or rheumatoid arthritis, or people with weakened immune systems should ask their doctor before taking probiotics.
- Coenzyme Q10, 100 to 200 mg at bedtime, for antioxidant and immune system support. Coenzyme Q 10 may interact with blood thinners, such as warfarin (Coumadin), clopidogrel (Plavix), or aspirin and make them less effective, so ask your doctor before taking it.
Herbs can strengthen and tone the body's systems. As with any therapy, you should work with your health care provider before starting any treatment. You may use herbs as dried extracts (capsules, powders, teas), glycerites (glycerine extracts), or tinctures (alcohol extracts). Unless otherwise indicated, you should make teas with 1 tsp. herb per cup of hot water. Steep covered 5 to 10 minutes for leaf or flowers, and 10 to 20 minutes for roots. Drink 2 to 4 cups per day. You may use tinctures alone or in combination as noted.
These herbs have not been studied specifically for histoplasmosis, but they seem to stop the growth of some fungus.
- Cat's claw (Uncaria tomentosa) standardized extract, 20 mg, 3 times per day, to reduce inflammation and stop the growth of fungus. Cat’s claw may boost the immune system, so people with autoimmune diseases (such as rheumatoid arthritis or psoriasis) may want to avoid it. People with leukemia should not take cat's claw. Cat's claw may interact with a number of medications, so ask your doctor before taking it.
- Garlic (Allium sativum), standardized extract, 400 mg, 2 to 3 times per day, to kill fungus and boost the immune system. Garlic may increase the risk of bleeding. Ask your doctor before taking garlic if you also take blood thinners, such as aspirin, clopidogrel (Plavix), or warfarin (Coumadin). Garlic may interact with some medications, including some medications used to treat HIV/AIDS, as well as some birth control medications. Speak with your doctor.
- Cranberry (Vaccinium macrocarpon), 300 to 1,800 mg, 2 times per day, to fight fungus. Cranberry contains salicylic acid, the same ingredient in aspirin. People with aspirin sensitivity, and people who take the blood thinners warfarin (Coumadin) or clopidogrel (Plavix) should ask their doctor before taking cranberry.
- Reishi mushroom (Ganoderma lucidum), 150 to 300 mg, 2 to 3 times per day, to reduce inflammation and strengthen the immune system. You may also take a tincture of this mushroom extract, 30 to 60 drops, 2 to 3 times a day. Reishi may interact with blood pressure medications and blood-thinning medications.
- Olive leaf (Olea europaea) standardized extract, 250 to 500 mg, 1 to 3 times per day, for antifungal activity and immunity. You may also prepare teas from the leaf of this herb. Olive leaf can lower both blood pressure and blood sugar. If you take medications for high blood pressure or diabetes, ask your doctor before taking olive leaf.
Warnings and Precautions
The medications used to treat histoplasmosis may interact with a number of other drugs. Be sure to tell your doctor about all the medications you take. Amphotericin can be toxic to the kidneys, so your doctor will watch you carefully while you take it.
Prognosis and Complications
Most people don't have serious complications, but rarely they may include:
- Fibrous tissue in the lining of the chest wall cavity, which may squeeze the esophagus, heart, or lungs, so they cannot work properly
- Scar tissue in the lungs
- Blindness -- if infection spreads to the eyes
Most cases of histoplasmosis are mild, and symptoms go away in 10 days without treatment. Sometimes symptoms may last for several weeks. In the most severe cases, particularly when the infection spreads throughout the body, a person may need to take antifungal medications for a long time. If left untreated, severe cases can cause death. People in areas where the fungus is common may get a second infection, even after treatment. But the second one is usually milder than the first.
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Parasitic infection - histoplasmosis
- Last reviewed on 12/6/2014
- Steven D. Ehrlich, NMD, Solutions Acupuncture, a private practice specializing in complementary and alternative medicine, Phoenix, AZ. Review provided by VeriMed Healthcare Network. Also reviewed by the A.D.A.M. Editorial team.
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