Tuberculosis (TB)

What is tuberculosis?

Tuberculosis (TB) is a chronic bacterial infection that usually infects the lungs, although other organs are sometimes involved. TB is primarily an airborne disease (spread by air droplets from infected people when they cough or sneeze).

There is a difference between being infected with the TB bacterium without illness and having active tuberculosis disease.

There are three ways to describe the stages of TB. They are as follows:

• Exposure. This occurs when a person has been in contact with, or exposed to, another person who has TB, but does not become infected himself or herself. The exposed person will have a negative TB skin test, a normal chest X-ray, and no symptoms of the disease.
• Latent TB infection. This occurs when a person has been exposed to TB, and has the TB bacteria in his or her body, but does not have symptoms of the disease. The infected person's immune system walls off the TB organisms, and they remain dormant throughout life in 90 percent of people who are infected. This person would have a positive skin test, a normal chest X-ray, and no illness.
• TB disease. This describes the person who has symptoms of an active infection. This person would have a positive skin test, a positive chest X-ray, and might be ill.

The predominant TB bacterium is Mycobacterium tuberculosis (M. tuberculosis). Many people infected with M. tuberculosis never develop active TB. Those who do usually develop TB only in the lungs. However, in people with weakened immune systems, including those with HIV (human immunodeficiency virus) or diabetes and those who are treated with medications that can weaken the immune system, such as corticosteroids and chemotherapy, TB organisms can overcome the body's defenses, multiply, and cause an active disease. Very young children are more likely than older children and adults to have TB spread through their bloodstream and cause complications, such as meningitis.

Who is at risk for developing TB?

TB affects all ages, races, income levels, and both genders. Those at higher risk include the following:

• People who live or work with others who have TB
• Medically underserved populations
• Homeless people
• People from other countries where TB is prevalent
• People in group settings, such as nursing homes
• People who abuse alcohol
• People who use intravenous drugs
• People with impaired immune systems
• The elderly
• Health care workers who come in contact with high-risk populations

What are the symptoms of TB?

Different symptoms of TB are present depending upon the age of the child affected. The following are the most common symptoms for TB. However, each child may experience symptoms differently. Symptoms may include:

• In children:
  • Fever
  • Decrease in weight
  • Sweating at night
  • Cough
  • Swollen glands
  • Chills
• In adolescents:
  • Cough that lasts greater than three weeks
  • Productive cough
  • Pain in the chest
  • Blood in their sputum
  • Fatigue
  • Swollen glands
  • Weight loss
  • Decrease in appetite
  • Fever
  • Night sweats

The symptoms of TB may resemble other lung conditions or medical problems. Always consult your child's doctor for a diagnosis.

What causes TB?

The TB bacterium is spread through the air when an infected person coughs, sneezes, speaks, sings, or laughs; however, repeated exposure to the germs is usually necessary before a person will become infected. It is not likely to be transmitted through personal items, such as clothing, bedding, a drinking glass, eating utensils, a handshake, a toilet, or other items that a person with TB has touched. Adequate ventilation is the most important measure to prevent the transmission of TB.

How is TB infection diagnosed?

TB is diagnosed with a TB skin test. In this test, a small amount of noninfectious testing material derived from the TB bacterium is injected into the top layer of the skin. If a certain size bump develops within two or three days, the test may be positive for tuberculosis infection. Additional tests to determine if a child has TB disease include X-rays and sputum tests.

TB skin tests are suggested for those:

• In high-risk categories.
• Who live or work in close contact with people who are at high risk.
• Who have never had a TB skin test.

Recommendations for skin testing in children, from the American Academy of Pediatrics are as follows:

Immediate testing:

• If the child is thought to have been exposed in the last five years.
• If the child has an X-ray that indicates possible TB.
• If the child has any symptoms of TB.
• A child who is coming from countries where TB is prevalent.

Yearly skin testing:

• Children with HIV.
• Children who are in detention facilities.

Testing every 2 to 3 years:

• Children who are exposed to high-risk people.

Consider testing in children at ages 4 to 6 and 11 to 16 if:

• A child's parent has come from a high-risk country.
• A child has traveled to high-risk areas.
• Children who live in densely populated areas.

Treatment for tuberculosis

Specific treatment will be determined by your doctor based on:

• Your age, overall health, and medical history
• Extent of the disease
• Your tolerance for specific medications, procedures, or therapies
• Expectations for the course of the disease
• Your opinion or preference

Treatment may include:

• Short-term hospitalization
• Medications
• For latent TB in children ages 2 to 11. Usually a six- to 12-month course of isoniazid will be given to kill off the TB organisms in the body.
• For active TB in children doctors may prescribe three to four medications at once including isoniazid, rifampin, pyrazinamide, or streptomycin for a period of time up to six months or more for the medication to be effective.

Patients usually begin to improve within a few weeks of the start of treatment. After two weeks of treatment with the correct medications, the patient is not usually contagious, provided that treatment is carried through to the end, as prescribed by a doctor.

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