Lack of adherence to isoniazid chemoprophylaxis in children in contact with adults with tuberculosis in Southern Ethiopia.

Hawassa, Southern Region of Ethiopia.To determine compliance to isoniazid (INH) preventive therapy (IPT) and its effectiveness in preventing (TB) disease in children in contact with adults with pulmonary TB (PTB).This was a prospective cohort study of children 5 years old were given advice but did not receive IPT, as recommended by the National TB control programme. Compliance to IPT and incidence of clinical TB were determined monthly for six months and then quarterly for up to 30 months.One hundred and eighty four children in contact with 83 smear-positive PTB cases were identified. Eighty two were ≤5 and 102>5 years old. Only 27 (33%) of 82 children given IPT took it for >4 months and 10 (12%) completed the 6-month course. The main reason for non-compliance was the perception that drugs were not necessary when the child was healthy. Eleven children (all except one >5 years old) developed symptoms of TB disease and initiated treatment, resulting in an incidence of 28.6 cases for all and 53.5 for children >5 years old per 1000 children-year.Compliance to IPT in children is poor in Southern Region of Ethiopia and this was associated with the parents' perception of the low importance of chemoprophylaxis in asymptomatic children. Poor compliance might be an important barrier for the wider implementation of IPT.Clinicaltrials.gov NCT00456469

Characteristics of children who received and not received INH prophylaxis.

<p>N = number, SD, Standard deviation, mm = millimeter, TST = Tuberculin skin test.</p

Characteristics of children with and without TB disease among those followed.

<p>*Chi square for trend, N = number, TB = tuberculosis, mm = millimeter, SD = Standard deviation.</p

Characteristics of children who developed tuberculosis disease (N = 11).

<p>*At the time of enrolment.</p><p>**Presence of windows in the home; NA = Not available. EPTB = Extrapulmonary TB, SS+ PTB = Smear positive pulmonary TB, SS− PTB = Smear negative pulmonary TB, Neg = negative, TST = Tuberculin skin test.</p

Use of tuberculin skin test, IFN-γ release assays and IFN-γ-induced protein-10 to identify children with TB infection.

Current tests of tuberculosis (TB) infection (tuberculin skin test (TST), interferon (IFN)-γ-release assays (IGRAs) and IFN-γ-induced protein (IP)-10) have limitations and their value when used consecutively to identify infected children has not been explored. This study describes TST, IGRA and IP-10 responses in children in contact with adults with TB, the agreement of the tests and whether using multiple tests indentifies more infected children. 330 children (aged 1-15 yrs) in contact with adults with pulmonary TB and 156 controls were studied in Ethiopia. Children exposed to adults with high bacilli grades in sputum were more likely to have positive TST, IFN-γ and IP-10 than controls. The agreement of positive tests was directly associated with the sputum bacilli grades (p<0.001 for all). The agreement of negative tests was higher in control children. The consecutive use of the tests increased the number of children classified as having at least one positive test. Using three tests increases the number of children classified as infected. This increase is associated with the bacilli load of the adults. Using only one test may underestimate the proportion of infected children, but the interpretation of the data is difficult due to the lack of reference standards