Tuberculosis in Pregnancy
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Direct answer
Tuberculosis in pregnancy is treated with the full first-line regimen, because untreated maternal disease carries more risk to mother and fetus than the drugs do. Isoniazid, rifampicin, pyrazinamide and ethambutol are used with pyridoxine supplementation, while streptomycin is avoided because it causes fetal eighth-nerve toxicity. Breastfeeding is generally allowed once the mother is on effective treatment, and the exposed infant receives isoniazid preventive therapy.
What you must remember
- Diagnosis: Sputum CBNAAT is the first test under the national programme; chest radiography is safe with abdominal shielding, and culture gives drug sensitivity.
- Initial regimen: Two months of isoniazid, rifampicin, pyrazinamide and ethambutol, followed by four months of isoniazid and rifampicin (the national programme continues ethambutol as well, 4HRE) for drug-sensitive disease.
- Pyridoxine: Given with isoniazid to prevent peripheral neuropathy, particularly in women with HIV.
- Streptomycin: Avoided in pregnancy because it crosses the placenta and damages the fetal eighth cranial nerve.
- Congenital TB: Rare; it is diagnosed on gastric or tracheal aspirate from the newborn when symptoms or exposure suggest infection.
- Breastfeeding: Generally allowed once the mother has started effective therapy, with precautions while she remains infectious.
- Exposed infant: Receives isoniazid preventive therapy and is examined for active disease.
A pathway from diagnosis to the infant
Tuberculosis in pregnancy is managed as a standard case, with added attention to drug safety and to the newborn. The steps below run from diagnosis to the infant.
- Diagnose early: Send sputum for CBNAAT and culture; a negative smear does not exclude TB in a pregnant woman with compatible symptoms.
- Start full therapy: Begin the standard four-drug intensive phase promptly, because delay harms mother and fetus.
- Add pyridoxine: Give vitamin B6 with isoniazid to prevent peripheral neuropathy, especially in women with HIV.
- Test for HIV: Offer HIV testing to every patient with TB, since co-infection changes the treatment and prophylaxis plan.
- Evaluate the newborn: Examine an infant whose mother had active disease near delivery, with gastric aspirate testing if symptoms are present.
- Manage feeding and prophylaxis: Breastfeeding continues on effective therapy, and the infant receives isoniazid preventive therapy as per national guidance.
Treatment is supervised through the national programme, with directly observed dosing and regular review of response and drug toxicity. Liver function is checked if the woman develops jaundice or symptoms, because hepatotoxicity from the first-line drugs is the main concern during the intensive phase.
Where the examiner tries to catch you
Viva questions test drug safety in pregnancy and the infant plan.
- Trap: Withholding first-line drugs because the pregnancy is early Correct: Untreated active TB is more dangerous to mother and fetus, and first-line drugs are used in all trimesters with pyridoxine.
- Trap: Choosing streptomycin as a safer alternative in pregnancy Correct: Streptomycin causes fetal eighth-nerve toxicity, so it is avoided.
- Trap: Advising mothers with TB to stop breastfeeding automatically Correct: Breastfeeding is generally allowed once effective therapy has started, and prophylaxis covers the exposed infant.
Frequently asked questions
Which first-line antitubercular drug is avoided in pregnancy?
Streptomycin is the first-line drug avoided in pregnancy because it causes eighth cranial nerve toxicity in the fetus. Isoniazid, rifampicin, pyrazinamide and ethambutol are used in pregnancy under the national programme.
Why is pyridoxine given with isoniazid in pregnancy?
Pyridoxine is given with isoniazid in pregnancy to prevent peripheral neuropathy, a side effect of isoniazid. It is especially important in women with HIV, and it does not reduce the drug's effect on tuberculosis.
Is breastfeeding safe for a mother receiving tuberculosis treatment?
Breastfeeding is generally allowed for a mother receiving effective tuberculosis treatment, because the first-line drugs pass into milk only in modest amounts. The exposed infant receives isoniazid preventive therapy and is examined for active disease.
How is congenital tuberculosis diagnosed in a newborn?
Congenital tuberculosis is diagnosed by testing the infant's gastric or tracheal aspirate for Mycobacterium tuberculosis, usually by CBNAAT, when symptoms or exposure suggest infection. It is rare, and it should be considered in a newborn with unexplained fever, respiratory distress or hepatosplenomegaly.