Effectiveness of isoniazid preventive therapy (IPT) and risk factors for IPT failure in children below 5 years of age who are household contacts of smear positive adult patients with tuberculosis

Introduction: Childhood tuberculosis (TB) is yet a major problem in developing countries. Isoniazid preventive therapy (IPT) is recommended for children below 5 years of age who are household contacts of smear positive adult TB patients. Objectives: To assess effectiveness of the six month IPT therapy and the risk factors for IPT failure in children less than 5 years old who are household contacts of smear positive adult TB patients. Method: A prospective longitudinal cohort study was carried out in the Surabaya Public Health Centre from January to June 2019 in children below 5 years of age who were household contacts of smear positive adult TB patients and who were given isoniazid for 6 months. Bivariate analysis using Chi-Square test and multivariate analysis were used. p <0.05 was considered significant. Results: Ninety one children below 5 years of age met the inclusion criteria and were included in study. Efficacy of IPT was 95.5%. In multivariate analysis, the risk factors associated with IPT failure were child contacts living in house without ventilation (p = 0.007) and incomplete IPT (p = 0.007). Conclusions: Efficacy of IPT in reducing the incidence of TB in children below 5 years of age who were household contacts of smear positive adult TB patients was 95.5%. Low adherence to completion of therapy and unavailability of house ventilation were associated with IPT failure.