Missed opportunities for diagnosis and treatment in patients with tuberculosis symptoms: a systematic review

Abstract

Background Identification of symptomatic patients followed by prompt on-site investigation form the foundation of facility-based tuberculosis (TB) screening and diagnosis. However, underdiagnosis is common, contributing to ongoing transmission and adverse health outcomes. We conducted this systematic review with the hypothesis that underdiagnosis is largely secondary to to failure of the symptom-screen-based approach to efficiently identify patients at risk of TB. Methods We searched (to 22 January 2019) MEDLINE, Embase, and Cinahl for studies investigating the pathway of care for patients (and standardised patients) presenting to health facilities or pharmacies with TB symptoms. We used QUADAS-2 to assess risk of bias. We reported the proportions of symptomatic patients at each stage of the diagnostic and care pathway from symptom screening to treatment initiation. We adhered to the PRISMA statement throughout this work. Results After screening 3,184 titles and abstracts, we identified 14 eligible studies. None provided data addressing the full cascade of care from clinical presentation to treatment initiation in the same patient population. Symptom-screening, the critical entry point for diagnosis of TB, was not done for 40%, 50%, and 96% of symptomatic participants in the three studies that reported this outcome. The proportion of symptomatic attendees offered a diagnostic investigation (data available for 13 studies), was very low with a study level median of 38% (IQR: 22% to 45%, range 5% to 84%).Conclusions Inefficiencies of the TB symptom screen-based patient pathway are a major contributor to underdiagnosis of TB in health facilities, and reflect inconsistent implementation of longstanding guidelines to ask all patients attending health facilities about respiratory symptoms and to offer diagnostic tests to all patients promptly once TB symptoms are identified. Screening tools and interventions with better diagnostic performance than symptoms, are urgently needed to improve the efficiency of TB care pathways in health facilities.