Predictors of treatment outcomes of childhood tuberculosis among patients attending the TB clinic at Mbagathi County Hospital, Nairobi County

Abstract

Background: Globally, tuberculosis (TB) is the leading cause of death by a single infectious agent. An estimated one million children develop tuberculosis disease, and an estimated 233,000 die from its complications worldwide each year. Kenya is among the 30 high TB burden countries which accounted for 87% of the world’s cases. In 2019, 86,385 TB cases were notified in Kenya among which 8,393 were children aged below 15 years. Unlike studies on TB in adults, there is limited published data for the predictors of treatment outcomes in children. The aim of TB treatment policy is to cure patients and therefore alleviate suffering and prevent death from the disease. It’s also aimed at preventing long-term complications arising from the disease and prevent relapse. Treatment is also aimed at preventing the transmission of the infection and development of drug resistance. Outcomes of treatment is a good indicator of the performance of the TB program.

Objectives: To determine the predictors of treatment outcomes of childhood tuberculosis among patients attending the TB clinic at Mbagathi County Hospital, Nairobi County

Design: A three-year retrospective study.

Setting: Tuberculosis clinic at Mbagathi County Hospital, Nairobi

Subjects: Files of patients aged below 15 years registered for treatment of TB at Mbagathi County Hospital between 1st January, 2018 and 31st December, 2020.

Results: The findings of the study showed the proportion of males and females were comparable at 62 (49.2%) and 64 (50.8%), respectively. Of these children, 64 (50.8%) were aged < 1 year and 47 (37.3%) had severe acute malnutrition. Of all the study subjects, 80 (63.5%) had pulmonary TB, 39 (31.0%) had extra-pulmonary TB and 4 (3.2%) had miliary TB. The HIV testing rate was 115 (91.2%) with the HIV positivity rate of 28 (22.2%). Genexpert test was done in 54 (42.9%) children out of which 30 (55.6%) had Mycobacterium tuberculosis (MTB) detected. Good/favourable treatment outcomes were observed in 68 (53.9%) of respondents. Among the 19 children aged between 1 year and < 5 years, 13 (68.4%) had good treatment outcomes and was highest compared to the other age groups. Age was significantly associated with treatment outcome (Fishers Exact test, p<0.05). Out of 116 children whose DOT supporter was a household member, 63 (54.4%) had good treatment outcomes and was significantly associated with treatment outcome (Fishers Exact test, p<0.05). Among 82 children who had pulmonary tuberculosis, 50 (61.0%) compared to 18 (43.9%) of 41 children with EPTB had good treatment outcome. On binary logistic regression, the type of TB was the only variable that significantly contributed to the model.

Conclusion: Children below one year of age contributed the highest TB burden and malnutrition being a very important factor associated with TB disease. Pulmonary TB remained the predominant type of the disease and HIV positivity rate was double the national scale. Most children were self-referrals and those whose treatment outcomes were not evaluated contributed a high proportion of poor treatment outcomes.

Recommendation: A better referral framework should be implemented so as capture data particularly for treatment outcomes.  Multi-centre research that is more representative is also recommended.