Dear Dr. Gott: Following Up on a Positive TB Skin Test

Dear Dr. Gott: I will soon marry a wonderful young man who just told me that he had a positive skin test for TB years ago and was prescribed medication for months, after which his doctor said he should be re-checked once a year. What does this mean? Should I worry? Is TB contagious? What is TB?

Dear Reader: Tuberculosis is a bacterial infection that is common the world over, but relatively rare (thank goodness) in the United States.

The disease is spread by inhaling respiratory droplets from an infected person (at work, on the subway, on an airline flight and so forth). Thus, the infection leads to lung problems and, if untreated, can spread to other body organs with serious consequences. Symptoms include malaise, a persistent cough, weight loss and low-grade fever. On occasion, the sputum may be tinged with blood.

Fortunately, not everyone exposed to TB becomes ill. In these instances, the body effectively controls the infection — but does not cure it; the TB bacteria simply remain dormant for decades, only to reactivate at a later date, as we age and our immune systems become less efficient. During the immune phase, the body makes proteins to deactivate the TB germs. These proteins can be identified in the skin during a simple inoculation of PPD (Purified Protein Derivative), which causes slight skin swelling in 72 hours. This reaction can easily be measured.

If the test is positive, the patient should have a chest X-ray. In the presence of inflammation (shadows on the X-ray film), he is then identified as having active TB that must be further diagnosed (by a sputum analysis) and aggressively treated for many months.

If, on the other hand, the chest X-ray is normal, the assumption is that the patient has a dormant, inactive infection that is treated for six to nine months with an antibiotic. Following this, annual X-ray follow-ups are the rule.

It sounds to me that your fiance has had appropriate medical attention and treatment. I doubt that he is contagious. You are at no risk — providing his X-ray studies are normal and current.

However, you have possibly been exposed. Therefore, to be especially cautious, you might consider having a skin test. Ask your family physician about this.

To give you related information, I am sending you a copy of my Health Report “Pulmonary Disease.” Other readers who would like a copy should send a long, self-addressed, stamped envelope and $2 to Newsletter, P.O. Box 167, Wickliffe, OH 44092. Be sure to mention the title.

If readers would like to contact Dr. Gott, they may write him through your newspaper or send their mail directly to Dr. Gott c/o United Media, 200 Madison Ave., 4th fl., New York, NY 10016. However, if readers want to request a newsletter, they should write to the Ohio address.