Newborns can be exposed to the bacteria in various ways.
Symptoms include fever, reduced energy, and difficulty breathing.
The diagnosis may involve a chest x-ray, a blood test, examination and culture of fluid and tissue samples, and a spinal tap.
An antibiotic may be given to infants who have been exposed to someone who has an active infection even if they are not sick.
Infected newborns and pregnant women are given antibiotics to treat the infection.
Infants become infected when they are exposed to Mycobacterium tuberculosis. Infants can be exposed in several ways:
Before birth: Infection occurs if the bacteria cross the placenta (the organ that provides nourishment to the fetus) and infect the fetus.
During birth: Infection occurs if the newborn breaths in or ingests infected fluid from the birth canal.
After birth: Infection occurs if the newborn inhales infected droplets that have been coughed or sneezed into the air by family members or nursery personnel.
About 50% of children born to mothers who have an active tuberculosis infection in their lungs develop the infection during the first year of life unless preventive antibiotics or a vaccine called bacille Calmette-Guérin (BCG) is given. People who have an active tuberculosis infection in their lungs are sick and can spread the disease to others.
Some newborns may have no symptoms.
Newborns may look ill and may have fever, reduced energy, difficulty breathing, or difficult-to-treat pneumonia. They may have a delay in weight gain and physical growth (failure to thrive). Because tuberculosis usually affects multiple organs, newborns may also have an enlarged liver and spleen.
Some newborns need testing and some do not.
Any newborn who has symptoms that suggest tuberculosis or who was born to a mother who has an active tuberculosis infection receives the following tests:
A chest x-ray may show signs of tuberculosis.
Fluid and tissue samples are taken from the throat, stomach, urine, and placenta. These samples are examined under a microscope to look for tuberculosis bacteria and are used to grow the bacteria in a culture.
A spinal tap (lumbar puncture) is done to obtain a sample of spinal fluid for testing.
Blood tests are done to determine whether the newborn has any other infections, such as human immunodeficiency virus (HIV) infection.
Sometimes newborns are given a tuberculosis skin test. In this test, a small amount of protein derived from tuberculosis bacteria (tuberculin) is injected just under the skin. About 2 days later, the injection site is checked. If the injection site is larger than a certain size, the test is considered positive, indicating that the newborn has been infected with the tuberculosis bacteria. However, sometimes the test does not show infection even if the newborn is infected. In these cases, if doctors are still concerned, they may do additional tests.
Any newborn who looks well and whose mother has a positive skin test but no signs of tuberculosis on a chest x-ray and no evidence of an active tuberculosis infection should be closely monitored by doctors. All their household members should be evaluated. If after the evaluation doctors determine the newborn has not been exposed to an active tuberculosis infection, the newborn does not need treatment or testing. If after the evaluation doctors determine the newborn has been exposed to an active tuberculosis infection, the newborn is given the tests described above.
Doctors typically give the antibiotic isoniazid to infants who have been exposed to an active tuberculosis infection even if they are not ill because this drug helps prevent the infection from becoming active.
In much of the developing world, where the risk of developing tuberculosis is higher, newborns are routinely given a vaccine called bacille Calmette-Guérin (BCG) to help prevent childhood tuberculosis. Doctors usually do not recommend the BCG vaccine for people living in developed countries because the risk of infection is lower.
Newborns who have an active tuberculosis infection may be treated with a combination of the antibiotics isoniazid, rifampin, pyrazinamide, ethionamide, and ethambutol and sometimes other drugs.
Newborns who have a positive skin test or who are exposed to active tuberculosis after birth are given isoniazid to prevent the infection from developing.
In newborns, all drugs for tuberculosis are taken for 6 months or longer.
Pregnant women who are at high risk of developing tuberculosis are given isoniazid along with supplemental vitamin B6 (pyridoxine) for 9 months. Some women exposed to tuberculosis during pregnancy may not be given isoniazid and vitamin B6 until after the first trimester or after delivery depending on their risk of developing active tuberculosis.
Pregnant women who have an active tuberculosis infection are given a combination of isoniazid, ethambutol, and rifampin for at least 9 months or longer.