Introduction:

Histoplasmosis is an infection caused by a fungus, called Histoplasma capsulatum (H. capsulatum). The fungus lives is the soil, and is breathed in through a person' s lungs. Most people with histoplasmosis develop 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 for people with weakened immune systems or who have chronic diseases, or for infants, histoplasmosis can be serious. Rarely, it can lead to death.

Because of the similarity in symptoms, histoplasmosis is sometimes mistaken for tuberculosis. About 500,000 people are exposed to H. capsulatum each year in the United States.

Signs and Symptoms:

Most cases of histoplasmosis produce 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
• Chronic 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:

• Anemia
• Meningitis (inflammation of the membranes of the brain and spinal cord)
• Ulcers in the mouth
• Infection of heart valves
• Pneumonia
• Enlarged liver and spleen
• Swollen lymph nodes

Causes:

Histoplasmosis is caused by exposure to 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. The spores of fungus are breathed into the lungs, where they multiply. 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.

Risk Factors:

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

Diagnosis:

Because most people with histoplasmosis have no symptoms, the condition 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 in cases where someone needs immediate treatment
• Fungal stain or blood test
• Chest x-ray or computerized tomography (CT) scan

Preventive Care:

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 will help keep the spores from being released

Treatment:

Mild cases of histoplasmosis may not need treatment. More serious cases, with symptoms that include high fever, trouble breathing, loss of appetite, and malaise, are treated with antifungal medications.

Medications

Medications used to treat histoplasmosis stop the fungus from growing in the body. These medications are often used 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

A comprehensive treatment plan for histoplasmosis may include a range of complementary and alternative therapies. 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 these 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 - 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 - 1,000 mg one to three times daily. Vitamin C is an antioxidant and may help strengthen the immune system.
• Grapefruit seed extract (Citrus paradisi), 100 mg capsule or 5 - 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 - 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.
• Coenzyme Q10, 100 - 200 mg at bedtime, for antioxidant and immune system support. Coenzyme Q 10 may interact with blood thinning medications such as warfarin (Coumadin) or aspirin, so ask your doctor before taking it.

Herbs

Herbs are generally a safe way to strengthen and tone the body's systems. As with any therapy, you should work with your health care provider to get your problem diagnosed 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 - 10 minutes for leaf or flowers, and 10 - 20 minutes for roots. Drink 2 - 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 three times per day, for to reduce inflammation and stop the growth of fungus. Cat' s claw is thought to increase the immune system response, so people with autoimmune diseases (such as rheumatoid arthritis or psoriasis) may want to avoid 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 two to three times per day, for antifungal and immune activity. 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).
• Cranberry (Vaccinium macrocarpon), 300 - 1,800 mg two times per day, for antifungal activity. Cranberry contains salicylic acid, the same ingredient in aspirin. People with aspirin sensitivity, and people who take the blood thinner warfarin (Coumadin) should ask their doctor before taking cranberry.
• Reishi mushroom (Ganoderma lucidum), 150 - 300 mg two to three times per day, to reduce inflammation and strengthen the immune system. You may also take a tincture of this mushroom extract, 30 - 60 drops two to three times a day. Reishi may interact with blood pressure medications and blood-thinning medications.
• Olive leaf (Olea europaea) standardized extract, 250 - 500 mg one to three 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.

Other Considerations:

Warnings and Precautions

The medications used to treat histoplasmosis may interact with a number of other medications. 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 the drug.

Prognosis and Complications

Fortunately, serious complications from histoplasmosis are very rare. These complications may include:

• Formation of fibrous tissue in the lining of the chest wall cavity, which may squeeze the esophagus, heart, or lungs, so they cannot work properly
• Meningitis
• Scar tissue in the lungs
• Blindness -- may occur if infection spreads to the eyes

Most cases of histoplasmosis are mild, and symptoms go away in 10 days without treatment. Occasionally symptoms may last for several weeks. In the most severe cases, particularly when the infection spreads to organs 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 infection is usually milder than the first.

Alternative Names:

Parasitic infection - histoplasmosis