Cost-effectiveness of active tuberculosis case finding using sputum Xpert MTB/RIF and acid-fast bacilli tests

Abstract

Background Active case finding (ACF) of tuberculosis (TB) has been recommended by the WHO for early detection of pulmonary TB. Nonetheless, there is little evidence about the cost-effectiveness of different ACF strategies. Objective The aim was to assess the cost-effectiveness of ACF using sputum Xpert MTB/RIF and acid-fast bacilli tests. Materials and methods Economic modeling was employed to assess the effectiveness and costs of three ACF strategies, based on applying Xpert MTB/RIF (‘Xpert only’), acid-fast bacilli (‘AFB only’), or both AFB and Xpert (‘AFB+Xpert’) in the screening protocols. Outcomes included TB case detection rate, lost to follow-up rate, costs, and incremental cost-effectiveness ratios of the strategies. Costs were estimated in US dollars from the societal perspective, with base year 2018. Results The ‘AFB only’ strategy showed a low case detection rate with higher costs, in relation to other strategies. Compared with the ‘Xpert only’ strategy, a rising rate of lost to follow-up was observed from the ‘AFB+Xpert.’ The case detection rate in the ‘Xpert only’ strategy is approximately twice the rate compared with the ‘AFB+Xpert’ strategy. The costs per TB case detected of the ‘AFB+Xpert’ and the ‘Xpert only’ strategies were $17 778.33 and $8334.47, respectively. The incremental cost-effectiveness ratio of the ‘Xpert only’ strategy was $257.28 per case detected as compared with the ‘AFB+Xpert’ strategy. Conclusion This study showed that the ‘AFB only’ strategy was dominated, in comparison with other strategies. It should not be recommended in the settings where application of Xpert MTB/RIF is feasible.