Isoniazid hepatitis among pregnant and postpartum Hispanic patients

On request of local health officials, the authors investigated isoniazid (INH) hepatitis morbidity and mortality among patients attending an Hispanic prenatal clinic. Among 3,681 women treated with INH during and after pregnancy to prevent tuberculosis (TB), 5 developed INH hepatitis, and 2 of the 5 women died. Comparison with previously collected Public Health Service data concerning 3,948 nonpregnant women, using the Cox proportional hazards model, revealed a 2.5-fold increased risk of INH hepatitis in the prenatal clinic group. The mortality rate was four times higher in the prenatal clinic group. However, statistical power was low because of the small number of cases, and neither of these findings was statistically significant (P greater than 0.05). In the absence of controlled studies, the issue of INH safety during the perinatal period remains unresolved. Nevertheless, current American Thoracic Society-Centers for Disease Control recommendations regarding TB screening, implementation of INH chemoprophylaxis programs, and adequate monitoring of individuals on INH should be adhered to. The results of this investigation raise concern that deviations from existing policy may contribute to unnecessary morbidity and mortality.