A rapid review of the causes of diagnostic and treatment delays for tuberculosis in low-burden countries

Abstract Background Delays in diagnosing and treating tuberculosis (TB) have significant implications. We undertook a rapid review to explore factors associated with delays at all stages of the diagnostic and treatment pathways in low-burden settings. Methods We searched databases (Embase, Medline, CENTRAL, Cinahl, PubMed, Cochrane Database of Systematic Reviews, and Web of Science) for qualitative and quantitative evidence (2010–25) from countries with low TB burden (incidence rate 40/100 000 in 2020). Included studies were assessed on their robustness and relevance. Due to the rapid review design, we did not conduct formal quality appraisal. Results The review included 3 reviews, 5 qualitative studies, 18 cohort studies, and 13 cross sectional studies (n = 41) with varying robustness and relevance. By synthesizing data using a patient pathway, we uncovered patient- and healthcare-related factors that contribute to delays such as medical history, health behaviours, level of patient and physician suspicion of TB, service location (primary care), and timing of TB testing. Having extrapulmonary TB was associated with greater total delay. Conclusions We have identified patient and health service factors that are consistently associated with patient, diagnostic, and total delay from TB symptom onset to initiation of treatment in low-burden settings. Factors amenable to change should be the focus of public health interventions aimed at reducing TB diagnostic delay.