What is histoplasmosis?

Histoplasmosis is an infection caused by the fungus Histoplasma. The fungus lives in soil. You get the infection by breathing in spores from the fungus. The infection most often affects the lungs.

Symptoms of histoplasmosis

Most healthy people who are infected with histoplasmosis never experience any symptoms. Their bodies fight off the disease. In people who do experience symptoms, the following are the most common:

  • fever
  • headache
  • cough
  • chest pain
  • chills
  • sweats
  • muscle aches
  • weight loss.

More severe cases of histoplasmosis include the following symptoms:

  • fever
  • night sweats
  • cough that may bring up blood
  • shortness of breath
  • pneumonia.

Rarely, the infection spreads through the whole body. This can happen in people with a weakened immune system. The symptoms include:

  • chest pain from inflammation around the heart
  • headache and stiff neck from inflammation around the brain and spinal cord
  • high fever.

What causes histoplasmosis?

Histoplasmosis is caused by a fungus that grows in the ground. Farming, construction, gardening, or any activity that disturbs the soil can release fungus spores into the air. If you breathe in those spores, you can get the infection.

You can’t catch histoplasmosis from another person or from an animal. Birds do not carry the infection. But their droppings provide food for the fungus in the ground. So you can get histoplasmosis in areas such as chicken coops. The droppings of bats also feed the fungus in the ground. So you can get histoplasmosis in areas where bats live, such as caves.

Who is most likely to get histoplasmosis?

The Histoplasma capsulatum fungus is one of the most common types in the United States. Histoplasmosis occurs in places that have moderate temperatures and moisture. It is very common in the Ohio, Missouri, and Mississippi river valleys. Damp, rich soil can be found in those areas.

People who work with soil or earth materials are at an increased risk for histoplasmosis. This includes farmers, landscapers, construction workers, archaeologists, and geologists.

Severe infections may develop in infants, young children, and older adults. Other people at an increased risk for developing severe cases of histoplasmosis include those who:

  • have HIV
  • are receiving chemotherapy treatment for cancer
  • are taking long-term corticosteroids (such as prednisone)
  • are taking anti-rejection medicines after an organ transplant.

A chronic infection can occur in patients who have lung diseases such as emphysema.

How is histoplasmosis diagnosed?

Your doctor can test your blood or urine for histoplasmosis. He or she can also take a sample of tissue for testing. Chest X-rays and computerized tomography (CT) scans are helpful for detecting inflammation in the lungs. This can help your doctor diagnose your condition.

Can histoplasmosis be prevented or avoided?

The best way to avoid infection is to stay away from places where you could breathe in contaminated dust. Spraying soil with water before digging or spraying barns and chicken coops can reduce the dust that gets stirred up. This reduces the number of fungus spores in the air. If you work in contaminated areas, you should wear protective clothing and face masks.

Histoplasmosis treatment

The treatment depends on how serious the infection is and how long the illness has lasted. Many people don’t need any treatment. The body will fight the infection on its own. Some people need to take an antifungal medicine. If you need to take medicine for histoplasmosis, your doctor will monitor you closely for possible side effects with your kidney or liver. You may need to take medicine for weeks or months. If you have AIDS, you may need to take this medicine for the rest of your life.

Some people have to go to the hospital to get oxygen therapy and intravenous fluids. Others can be treated at home. Most people respond well to treatment.

Living with histoplasmosis

It is important to see your doctor if you think you may have histoplasmosis. Left untreated, it could spread or cause scarring inside the lungs. Scarring can put pressure on your blood vessels, heart, esophagus, and lymph nodes.

If you develop a severe case of histoplasmosis, you may need to take medicine for a long time. This could be up to 1 or 2 years.

Questions to ask your doctor

  • How did I get histoplasmosis?
  • How do you know it’s histoplasmosis? Do I need any tests?
  • What should I do if my symptoms get worse?
  • What’s the best treatment option?
  • I don’t want to stop (farming, gardening, etc.). How do I avoid reinfection in the future?