( See also Tuberculosis (TB) in adults and Overview of Neonatal Infections.)
Infants may acquire tuberculosis (TB) by the following means:
Transplacental spread through the umbilical vein to the fetal liver
Aspiration or ingestion of infected amniotic fluid
Airborne inoculation from close contacts (family members or nursery personnel)
Symptoms and Signs of Perinatal TB
The clinical presentation of neonatal tuberculosis is nonspecific but is usually marked by multiple organ involvement. The neonate may look acutely or chronically ill and may have fever, lethargy, respiratory distress or non-responsive pneumonia, hepatosplenomegaly, or failure to thrive.
Diagnosis of Perinatal TB
Culture of tracheal aspirate, gastric washings, urine, and cerebrospinal fluid (CSF)
Chest x-ray
Sometimes skin testing
All neonates with suspected congenital tuberculosis and infants born to mothers who have active TB should have a chest x-ray and culture of tracheal aspirates, gastric washings, and urine for acid-fast bacilli; a lumbar puncture should be done to measure cell counts, glucose, and protein as well as to obtain CSF for culture. The placenta should be examined and cultured as well. Skin testing is not extremely sensitive, particularly initially, but should be done. TB-specific interferon-gamma release assays, which are useful in adults, are not approved for use in infants because of low sensitivity. Biopsy of the liver, lymph nodes, lungs, or pleurae may be needed to confirm the diagnosis. HIV testing of the infant should be done.
Well-appearing neonates whose mothers have a positive skin test but a negative chest x-ray and no evidence of active disease should have close follow-up, and all household members should be evaluated. If there is no exposure to a case of active TB, the neonate does not need treatment or testing. If significant exposure to a case of active TB is found in the neonate’s environment after birth, the neonate should be evaluated for suspected TB as described previously.
Pearls & Pitfalls
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Treatment of Perinatal TB
Management depends on the whether there is active TB disease or only a positive skin test (in mother, infant, or both) indicating infection without disease.
Pregnant women with a positive tuberculin test
Neonates with a positive tuberculin test
Pregnant women with active TB
Breastfeeding is not contraindicated for mothers receiving therapy who are not infective.
Patients with active TB should be reported to the local health department. Mothers with active TB should be tested for HIV.
Asymptomatic neonates whose mother or close contacts have active TB
The neonate is evaluated for congenital TB as above and is usually separated from the mother only until effective treatment of both mother and neonate is under way. If congenital TB is excluded and once the neonate is receiving INH, separation is no longer necessary unless the mother (or a household contact) has possible multidrug-resistant organisms or poorly adheres to treatment (including not wearing a mask if TB is active) and directly observed therapy is not possible. Family contacts should be investigated for undiagnosed TB before the infant goes home.
Skin testing should be done at age 3 or 4 months. If the neonate is tuberculin-negative and the initial infectious contact has adhered to treatment and has a positive response, INH is stopped. If the skin test is positive, chest x-ray and cultures for acid-fast bacilli are done as described previously and, if active disease is excluded, treatment with INH is continued for a total of 9 months. If cultures become positive for TB at any time, the neonate should be treated for active TB disease.
If adherence in a nontuberculous environment cannot be ensured, BCG vaccine may be considered for the neonate, and INH therapy should be started as soon as possible. (Although INH inhibits the multiplication of BCG organisms, the combination of BCG vaccine and INH is supported by clinical trials and anecdotal reports.) BCG vaccination does not ensure against exposure to and development of TB but offers significant protection against serious and widespread invasion (eg, tuberculous meningitis). BCG should only be given if skin and HIV test results of the neonate are negative. Neonates should be monitored for development of TB, particularly during the first year.
(CAUTION: BCG vaccine is contraindicated in immunosuppressed patients and those suspected of being infected with HIV. However, in high-risk populations, the World Health Organization [unlike the American Academy of Pediatrics] recommends that asymptomatic HIV-infected neonates receive BCG vaccine at birth or shortly thereafter.)
Neonates with active TB
Recommended Dosages of Select Aminoglycosides for Neonates
TB in infants and children that is not congenitally acquired or disseminated, does not involve the CNS, bones, or joints, and results from drug-susceptible organisms can be treated effectively with a 6- to 9-month (total) course of therapy. Organisms recovered from the child or mother should be tested for drug sensitivity. Hematologic, hepatic, and otologic symptoms should be monitored frequently to determine response to therapy and drug toxicity. Frequent laboratory analysis is not usually necessary.
Directly observed therapy is used whenever possible to improve adherence and the success of therapy. Many anti-TB drugs are not available in pediatric dosages. When possible, experienced personnel should give these drugs to children.
Prevention of Perinatal TB
Universal neonatal BCG vaccination is not routinely indicated in developed countries but may curb the incidence of childhood TB or decrease its severity in populations at increased risk of infection.
Key Points
Tuberculosis (TB) may be acquired transplacentally, through aspiration of infected amniotic fluid, or by respiratory transmission after birth.
Manifestations of neonatal TB are nonspecific, but multiple organs (including lungs, liver, and/or central nervous system) are usually involved.
Do chest x-ray and TB culture of tracheal aspirate, gastric washings, urine, and cerebrospinal fluid.
