Comparing tuberculosis in children aged under 5 versus 5 to 14 years old in a rural hospital in southern Ethiopia: an 18-year retrospective cross-sectional study.

Background: There are few data available about childhood tuberculosis (TB) in rural hospitals in low-income countries. We assessed differences in epidemiological characteristics and treatment outcomes in children with TB aged 0-4 versus 5-14 years in rural Ethiopia.

Methods: For this retrospective cross-sectional study, we analyzed childhood TB registers from a rural Ethiopian hospital. We collected data on the number of cases, type of TB, and treatment outcomes using standard definitions. By means of binary and logistic regression analyses, data were compared from 1998 to 2015 in children aged under 5 versus those aged 5-14 years.

Results: We included 1282 TB patients: 583 (45.5%) were under 5 years old, and 699 (54.5%) were aged 5-14 years. More than half (67.2%, n = 862) had pulmonary TB (PTB), which was more common in younger children (82.5%, 481/583) than in older ones (54.5%, 381/699; p < 0.001). Most cases of PTB (87.5%, 754/862) were smear negative, including virtually all (99.6%, 479/481) younger children and most older ones (72.2%, n = 275/381; p < 0.001). The most common types of extrapulmonary TB (EPTB) were TB adenitis (54.5%, 229/420) and bone TB (20%, 84/420). Children under five showed a lower prevalence of adenitis TB (9.9% [58/583] versus 24.5% [171/699], p < 0.001), bone TB (2.9% [17/583] versus 9.6% [69/699], p < 0.001), and abdominal TB (0.9% [5/583] versus 6.3% [44/699], p < 0.001). Most diagnoses were new cases of TB (98.2%, 1259/1282). Overall, 63.5% (n = 814) of the children successfully completed treatment (< 5 years: 56.6%, 330/583; 5-14 years: 69.2%, 489/699; p < 0.001). In total, 16.3% (n = 209) transferred to another center (< 5 years: 19.4%, 113/583; 5-14 years: 13.7%, 96/699; p = 0.006). Thirteen percent of patients (n = 167) were lost to follow-up (< 5 years: 16.0%, 93/583; 5-14 years: 10.4%, 74/699; p = 0.004). Fifty-two (4.1%) children died (no age differences). Being aged 5-14 years was independently associated with successful treatment outcomes (adjusted odds ratio 1.59; 95% confidence interval: 1.16, 1.94, p = 0.002).

Conclusions: We observed a very low diagnostic yield for spontaneous sputum smear in children with TB. In this rural setting in Ethiopia, very young children tend to present with new cases of smear-negative PTB. They have less EPTB than older children but more TB meningitis and show lower rates of treatment success.