AAP PARENTING CORNER Q & A: TUBERCULOSIS

How it is spread

Tuberculosis usually is spread when an infected adult coughs the bacteria into the air. These germs are inhaled by the child, who then becomes infected. (Children with TB of the lungs rarely infect other people, because they tend to have very few bacteria in their mucus secretions and also have a relatively ineffective cough.)

Fortunately, most children exposed to tuberculosis don?t become ill. When the bacteria reach their lungs, the body?s immune system attacks them and prevents further spread. These children have developed a symptom-free infection indicated only by a positive skin test. However, the symptom-free child still must be treated, as noted below, to prevent an active disease from ever occurring.

Symptoms

Occasionally, in a small number of children, the infection does progress, causing

In a very small number of children (mostly those less than four years old), the tuberculosis infection can spread through the bloodstream, affecting virtually any organ in the body. This illness requires much more complicated treatment, and the earlier it is started, the better the outcome. These youngsters have a much greater risk of developing tuberculosis meningitis, a dangerous form of the disease that affects the brain and central nervous system.

Diagnosis

The signs and symptoms of childhood TB can be difficult to detect. Often the only way you can tell for sure that a child has been exposed to this infection is by performing a skin test.

Your pediatrician will perform this so-called PPD (purified protein derivative of tuberculin) test, which is done by injecting a purified, inactive piece of TB germ into the skin. If there has been an infection, your child?s skin will swell and redden in the area of the injection. You?ll be asked to check for this area two days after the test is administered, since the reaction takes about forty-eight hours to appear. Your pediatrician should examine any reaction. This skin test will reveal past exposure to the bacteria, even if the child has had no symptoms and even if his body has fought the disease successfully.

If your child?s skin test for TB turns positive, a chest X ray will be ordered to determine if there is evidence of active or past infection in the lungs. If the X ray does indicate the possibility of active infection, the pediatrician also will search for the TB bacteria in your child?s cough secretions or in his stomach contents (obtained with a tube inserted into the nose down to the stomach). This is done in order to determine the type of treatment to be given.

Treatment

If your child?s skin test turns positive, but he does not have symptoms or signs of active tuberculosis infection (typically in an X-ray finding or the detection of TB bacteria in his saliva or stomach contents), he still is infected. In order to prevent the infection from becoming active, your pediatrician will prescribe a medication called isoniazid (INH). This medication must be taken by mouth once a day for a minimum of nine months.

For an active tuberculosis infection, your pediatrician may prescribe three or four medications. You?ll have to give these to your child for six to twelve months. Your youngster may have to be hospitalized initially for the treatment to be started, although most of it can be carried out at home.

Controlling the spread of TB

If your child has been infected with TB, regardless of whether he develops symptoms, it?s very important to attempt to identify the person from whom he caught the disease. Usually this is done by looking for symptoms of TB in everyone who came in close contact with him, and having TB skin tests performed on all family members, babysitters, and housekeepers. Anyone who has a positive skin test should receive a physical examination and a chest X ray.

When an actively infected adult is found, he?ll be isolated as much as possible?especially from young children?until treatment is under way. All family members who have been in contact with that person usually are also treated with INH, regardless of the results of their own skin tests. Anyone who becomes ill or develops an abnormality on a chest X ray should be treated as an active case of tuberculosis.

Tuberculosis is much more common in underprivileged populations, which are more susceptible to disease due to crowded living conditions, poor nutrition, and the probability of inadequate medical care. AIDS patients, too, are at a greater risk of getting TB, because of their lowered resistance.

If untreated, tuberculosis can lie dormant for many years, only to surface during adolescence, pregnancy, or later adulthood. At that time, not only can the individual become quite ill, but he also can spread the infection to those around him. Thus, it?s very important to have your child tested for TB if he comes in close contact with any adult who has the disease and to get prompt and adequate treatment for him if he tests positive.

The information contained in this publication should not be used as a substitute for the medical care and advice of your pediatrician. There may be variations in treatment that your pediatrician may recommend based on individual facts and circumstances.