Antepartum or postpartum isoniazid treatment of latent tuberculosis infection

Objective: To compare health outcomes and costs of different strategies for treatment of latent tuberculosis infection in pregnancy. Methods: Using a Markov decision-analysis model, the following three strate gies were evaluated for treatment of latent tuberculosis infection in pregn ancy, defined as positive tuberculin skin reaction of 10 mm or greater and negative chest radiograph: no treatment, antepartum isoniazid administratio n, in which women were given 300 mg of isoniazid with pyridoxine beginning at 20 weeks' gestation for 6 months; and postpartum isoniazid, in which wom en were given isoniazid and pyridoxine for 6 months after delivery. Sensiti vity analyses were performed for a wide range of probability and cost estim ates, and considered discount rates. Results: Under base-case assumptions, the fewest cases of tuberculosis with in the cohort occurred with antepartum treatment (1400 per 100,000) compare d with no treatment (3300 per 100,000) or postpartum treatment (1800 per 10 0,000). Antepartum treatment resulted in a marginal increase in life expect ancy due to the prevented cases of tuberculosis, despite more cases of ison iazid-related hepatitis and deaths, compared with no treatment or postpartu m treatment. Antepartum treatment was the least expensive. Only if the case -fatality rate for tuberculosis was tenfold lower than the base-case and th e risk of fatal hepatitis tenfold higher did antepartum treatment become th e least advantageous strategy. Conclusion: Rather than delaying treatment until postpartum, consideration for antepartum treatment of latent tuberculosis during pregnancy should be given. If isoniazid is not administered antepartum, then efforts to improve postpartum compliance should be instituted, as either antepartum or postpa rtum treatment is better than no treatment. (Obstet Gynecol 2000;96:757-62. (C) 2000 by The American College of Obstetricians and Gynecologists.).