Histoplasmosis is a fungal infection. It is caused by a fungus called Histoplasma capsulatum (H. capsulatum) that is found in soil. You breathe the fungus into your 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.

Most cases of histoplasmosis produce no symptoms or very mild ones. Signs and symptoms that occur in rare cases include the following:

• Sudden, flu-like infection -- includes fever, chills, cough, chest pain, and headache
• Chronic lung infection -- develops gradually over weeks to months and produces a progressive, worsening cough, weight loss, night sweats, and possibly, 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 occur after exploring caves.

When the disease spreads throughout the body, it affects many organ systems. A person may experience 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

Histoplasmosis is caused by exposure to the fungus H. capsulatum, 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 H. capsulatum. H. capsulatum grows in moist soil that is rich in nitrogen or in areas contaminated with bird or bat droppings, such as attics, barns, caves, and city parks. The spores of H. capsulatum are inhaled 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 gastrointestinal tract.

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 cases of histoplasmosis produce no symptoms, the condition can be difficult to diagnose. In addition to a physical exam, your doctor may perform the following tests:

• Fungal culture -- can take several weeks to confirm diagnosis, so this test is not used in severe cases where immediate treatment is needed
• Fungal stain or blood test
• Chest x-ray or computerized tomography (CT) scan

Although it would be ideal to prevent exposure to the fungus that causes histoplasmosis, it isn't easy -- the fungus is widespread. However, the following steps may help prevent infection:

• Wear masks or respirators when exposed to areas contaminated by bird or bat droppings
• Spray contaminated areas with water, which will help keep the spores from being released

Mild cases of histoplasmosis may not require 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 inhibit the growth of fungi 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) -- given orally

Surgery and Other Procedures

Surgery is only necessary in rare cases when serious complications arise. Some surgical procedures include:

• Laser photocoagulation -- procedure used to prevent loss of vision when infection spreads to the eyes
• Surgical resection -- procedure used to remove heart valves infected with H. capsulatum

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 incorporate 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 scientific evidence is lacking:

• Vitamin C, 500 - 1,000 mg one to three times daily, as an antioxidant, and for immune support.
• Grapefruit seed extract (Citrus paradisi), 100 mg capsule or 5 - 10 drops (in favorite beverage) three times daily when needed, for antibacterial, antifungal, and antiviral activity, and for immunity.
• N-acetyl cysteine, 200 mg daily, for antioxidant effects.
• 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 activity.

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.

• Cat's claw (Uncaria tomentosa) standardized extract, 20 mg three times per day, for inflammation and antifungal activity.
• Garlic (Allium sativum), standardized extract, 400 mg two to three times per day, for antifungal and immune activity.
• Cranberry (Vaccinium macrocarpon), 300 - 1,800 mg two times per day, for antifungal activity.
• Reishi mushroom (Ganoderma lucidum), 150 - 300 mg two to three times per day, for inflammation and for immunity. You may also take a tincture of this mushroom extract, 30 - 60 drops two to three times a day.
• 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.

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 monitor you carefully while you take the drug.

Prognosis and Complications

Fortunately, serious complications associated with histoplasmosis are extremely 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 function 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, however, symptoms may last for several weeks. The most severe cases, particularly when the infection spreads to organs throughout the body, may require taking antifungal medications for a long time. If left untreated, severe cases can result in 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.

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