FAMILY MEDICINE® COLUMN

By John C. Wolf, D.O.
Associate Professor of Family Medicine
Ohio University College of Osteopathic Medicine

HISTOPLASMOSIS -- DON’T FRET, LEAVE THE WORRYING TO YOUR DOCTOR

Question: I was told that histoplasmosis is everywhere, and if you have it, it usually stays dormant unless you become ill with a serious problem like cancer or AIDS. Is this true?

Answer: Histoplasmosis is a fungus that is prevalent from the temperate zones to the tropics worldwide. Areas that are contaminated by droppings from bats, chickens, pigeons, blackbirds and starlings are particularly rich in this fungus. However, you don’t need to live next to a bird coop to be exposed to the infecting fungal spores. Any construction or other activity that disturbs the contaminated soil will allow the wind to spread the spores for miles and miles. That is why histoplasmosis is so prevalent in most of the eastern part of the United States.

Your statement that “everyone” has histoplasmosis is almost true for those living in your state, Pennsylvania, as well as the rest of us in the eastern part of our country. Eighty percent of individuals 20 and older will test positive for this illness. Fortunately, most of these people have no idea that one of those “bad colds” or episode of the “flu” was actually an infection with this common fungus. The body’s immune system typically fights off the illness so that no medical intervention is needed.

Occasionally individuals who contract histoplasmosis will have a significant complication rather than the normal mild illness. These people can suffer from more serious lung inflammation or involvement with other organs. The lung involvement is much like the dreaded disease tuberculosis. The most common of the other-than-lung involvement are injury to your “food tube” (esophagus), an inflammation of the sack that surrounds the heart (pericarditis) and/or a type of non-cancerous chest tumor (mediastinal granulomas).

Illnesses such as AIDS impair the immune system, as can treatment for cancer, or taking anti-rejection drugs used for organ transplant recipients. These individuals have a substantially greater risk from a histoplasmosis infection. Often general malaise and fever are the initial symptoms rather than respiratory complaints. Enlargement of lymph nodes, liver and spleen are frequent signs, as are mouth ulcers -- which are present in up to 75 percent the cases. The illness can quickly progress to involve the central nervous system, skin and heart.

Histoplasmosis is benign and requires no treatment for most individuals. Those with more aggressive illness though, regardless of the underlying predisposing conditions, need medical attention. The use of IV medicine is often necessary in more severe cases, while others can safely be treated with oral anti-fungal drugs. Treatment is usually necessary for at least three months, but six months is not unusual. Despite treatment, those with an advanced -- but uncommon -- form of fungal lung infection (cavitary pulmonary histoplasmosis) often have progressively worsening disease. This may lead to respiratory failure and death.

So, just as you’ve heard, you shouldn’t worry much about having histoplasmosis. Most people have been exposed to it without any serious detrimental effect. On the other hand, we doctors think about it quite often when someone has a fever without an obvious cause or has a chronically worsening breathing problem. Enjoy your life. Let your doctor worry about histoplasmosis for you.

"Family Medicine" is a weekly column. To submit questions, write to John C. Wolf, D.O., Ohio University College of Osteopathic Medicine, P.O. Box 110, Athens, Ohio 45701. Past columns are available online at http://www.FamilyMedicineNews.org.