Costs and cost-effectiveness of Gene Xpert compared to smear microscopy for the diagnosis of pulmonary tuberculosis using real-world data from Arsi zone, Ethiopia

Abstract

Background Early diagnosis and treatment are one of the key strategies of tuberculosis control globally, and there are strong efforts in detecting and treating tuberculosis cases in Ethiopia. Smear microscopy examination has been a routine diagnostic test for pulmonary tuberculosis diagnosis in resource-constrained settings for decades. Recently, many countries, including Ethiopia, are scaling up the use of Gene Xpert without the evaluation of the cost and cost-effectiveness implications of this strategy. Therefore, this study evaluated the cost and cost-effectiveness of Gene Xpert (MTB/RIF) and smear microscopy tests to diagnosis tuberculosis patients in Ethiopia. Methods We compared the costs and cost-effectiveness of tuberculosis diagnosis using smear microscopy and Gene Xpert among 1332 patients per intervention in the Arsi zone. We applied combinations of top-down and bottom-up costing approaches. The costs were estimated from the health providers’ perspective within one year (2017–2018). We employed “cases detected” as an effectiveness measure, and the incremental cost-effectiveness ratio was calculated by dividing the changes in cost and change in effectiveness. All costs and incremental cost-effectiveness ratio were reported in 2018 US$. Results The unit cost per test for Gene Xpert was $12.9 whereas it is $3.1 for AFB smear microscopy testing. The cost per TB case detected was $77.9 for Gene Xpert while it was $55.8 for the smear microscopy method. The cartridge kit cost accounted for 42% of the overall Gene Xpert’s costs and the cost of the reagents and consumables accounted for 41.3% ($1.3) of the unit cost for the smear microscopy method. The ICER for the Gene Xpert strategy was $20.0 per tuberculosis case detected. Conclusion Using Gene Xpert as a routine test instead of standard care (smear microscopy) can be potentially cost-effective. In the cost scenario analysis, the price of the cartridge, the number of tests performed per day, and the life span of the capital equipment were the drivers of the unit cost of the Gene Xpert method. Therefore, Gene Xpert can be a part of the routine TB diagnostic testing strategy in Ethiopia.

Cost-effectiveness of TB diagnostic technologies in Ethiopia: a modelling study

“…The benefits of this strategy stem from improved sensitivity and specificity of the test when compared to other TB diagnostic tools. Our finding is in line with several studies that assessed the cost-effectiveness of TB diagnostic tests in sub-Saharan African countries, including Ethiopia, and found that the selected diagnostic platform to be highly cost-effective [ 12 , 36 , 39 ]. For instance, the current study base-case result for the X-pert MTB/RIF assay as a primary diagnostic test indicated an ICER of $274 per DALY averted, in contrast to previous studies’ findings of an ICER of $5 per DALY averted and $20 per TB case diagnosed, respectively.…”

“…In addition, the prior studies used a decision analysis framework with a shorter time horizon, our research employed a Markov model with a lifetime horizon, capturing a distinct sequence of events aligning with the natural history of TB disease. Additionally, there are variations in the choice of outcome measures and comparators, discounting, and disaggregation by HIV status [ 12 , 36 ]. However, our results are more comparable with another study conducted in Ethiopia, which found that the ICER of the rollout of X-pert MTB/RIF test would be $ 370 per DALY averted [ 40 ].…”

“…In addition, the national algorithm includes X-ray for screening of TB to improve the yield of TB diagnostic tools [ 7 , 11 ]. However, the country has low coverage of rapid TB diagnostic tests due to health-system resource constraints, including infrastructure, financing and human resources [ 12 ]. By 2020, only 10% of public health facilities have the capacity to do onsite rapid molecular diagnostic tests for TB, while additional 3500 health facilities are networked by a system for integrated specimen referral and result delivery [ 7 ].…”

Clinical diagnosis, treatment, and medical identification of specific pulmonary infection in naval pilots: Four case reports

“…Bronchoscopy can be improved when there are no cough and expectoration symptoms, and bronchial lavage fluid is inspected for pathogens. In Case 4, a small number of acid-fast bacilli was found in bronchial lavage fluid, and in Case 2, airway lesions were found under bronchoscopy, and GeneXpert is positive, so tuberculosis was diagnosed[ 7 ]. All four cases in this group had no obvious symptoms and signs, and abnormalities were found after chest CT scanning during physical examination.…”

Rapid Detection of Mycobacterium tuberculosis in Pleural Fluid Using Resuscitation-Promoting Factor-Based Thin Layer Agar Culture Method

“…Pleural biopsy with a high positive rate of 69.6–82% is not widely used as it is invasive, operator dependent, and technically difficult (particularly in children) ( Casalini et al, 2018 ). Besides, molecular tests like the Xpert MTB/RIF assay could report results within a few hours, but show poor sensitivities (22.7–51.4%), are expensive, and require special expertise ( Sehgal et al, 2016 ; Kaso and Hailu, 2021 ). Therefore, a rapid, simple, reliable, and cheap diagnostic test is urgently needed for pleural tuberculosis.…”