Non-completion of latent tuberculous infection treatment among children in Rio de Janeiro State, Brazil

BACKGROUND: Children with latent tuberculous infection (LTBI) are particularly vulnerable to progression to active tuberculosis (TB), and are thus a priority target for isoniazid preventive therapy (IPT). However, adherence to IPT is poor. We hypothesised that children from poorer families, with reduced access to health care and lack of understanding about the disease are more likely to default from IPT.

METHODS: A questionnaire was administered to close child contacts or their parents at the time of prescribing IPT in three cities in Rio de Janeiro State. The children were followed prospectively. Treatment adherence was defined as taking 80% of prescribed doses.

RESULTS: Among 1078 children screened for LTBI, 97 (8.9%) did not return for tuberculin skin test (TST) reading; 332 (30.8%) were TST-positive; 115/332 (34.6%) were prescribed IPT, 6 of whom did not initiate treatment and 11 did not adhere during the first 2 months; 25 additional children did not complete IPT. Overall non-completion was four times more frequent among those with lower income. Health care access and knowledge did not improve treatment completion.

CONCLUSIONS: Substantial losses to follow-up occurred before IPT prescription; this should be further investigated. Among the children who started isoniazid, low income, but not difficult access or poor knowledge, increased the risk of treatment non-completion.