Clinical Reference Systems: Pediatric Advisor 10.0

What is tuberculosis?

Tuberculosis (TB) is an infection caused by slow-growing bacteria. Tuberculosis usually causes lung disease but almost any part of the body can be affected.

Tuberculosis infections continue to be a serious problem for children in the U.S. More than 2,000 cases of TB infection are reported every year. However, at the time the infection is discovered, most infected children have no symptoms or x-ray signs of the disease. Most infections are discovered by a skin test before the infection has become serious enough to cause any problems.

If TB is detected before symptoms develop, your child can be treated with medications that will prevent the disease from continuing and spreading to others.

When should my child be tested?

Your child's doctor will determine how often a skin test is needed. Most children in the U.S. do not need to be routinely tested.

Children at high risk for TB should be skin tested. A child is considered high risk if:

• The child has been in close contact with people who have known or suspected TB infections.
• The child has an immunosuppressive condition or HIV infection.
• The child is from a region of the world with a high incidence of TB.
• The child has cancer.
• The child has diabetes.
• The child has kidney failure.
• The child is malnourished.
• The child has been imprisoned.

How does the test work?

The Mantoux test is the most accurate skin test. The Mantoux test involves injecting into your child's top skin layer a small amount of proteins from tuberculosis bacteria. This shot will not harm your child. The Mantoux test is more reliable than the multiple puncture tests, but as with any TB test, it may occasionally have false-positive or false-negative results.

The doctor will ask you to look at the area of skin where the shot was given 48 to 72 hours later, or the doctor may want your child to return to the office to have the area checked. Most children who have been infected with tuberculosis bacteria at least 6 weeks before the test will develop a raised, firm area and redness around the site of the injection.

Occasionally the redness will start more than 72 hours after the test. Tell your child's doctor if any redness appears. Your doctor will decide if the redness is from a tuberculosis infection or from some other cause.

Is there a vaccine for TB?

Bacillus Calmette-Guerin (BCG) is a vaccination given to prevent tuberculosis. This vaccine is usually given to people who do not have TB but are likely to come in contact with people who have the disease.

If your child has had the BCG vaccine, be sure to tell your child's doctor. The BCG vaccine may cause the skin to become red after a TB skin test, suggesting that your child has TB even when he or she does not.

When should I call my child's doctor?

Call your child's doctor during office hours if:

• Redness appears around the area where your child's skin was tested.
• You believe your child may have been exposed to someone with tuberculosis.
• You have other questions or concerns.