Study protocol: a cluster randomized trial to evaluate the effectiveness and implementation of onsite GeneXpert testing at community health centers in Uganda (XPEL-TB)

Abstract

Background: Delays in diagnosis and treatment of tuberculosis (TB) remain common in high-burden countries. To improve case detection, substantial investments have been made to scale-up Xpert MTB/RIF (Xpert), a cartridgebased nucleic acid amplification test that can detect TB within 2 hours, as a replacement for sputum smear microscopy. However, the optimal strategy for implementation of Xpert testing remains unclear. Methods: The Xpert Performance Evaluation for Linkage to Tuberculosis Care (XPEL-TB) trial uses an ultra-pragmatic, hybrid type II effectiveness-implementation design to assess the effectiveness and implementation of a streamlined strategy for delivery of Xpert testing in real-world settings. Twenty health centers with TB microscopy units were selected to participate in the trial, with ten health centers randomized to the intervention strategy (onsite molecular testing using GeneXpert Edge, process redesign to facilitate same-day TB diagnosis and treatment, and performance feedback) or routine care (onsite sputum smear microscopy plus referral of sputum samples to Xpert testing sites). The primary outcome is the number of patients with microbiologically confirmed TB who were initiated on treatment within 14 days of presentation to the health center, which reflects successful completion of the TB diagnostic evaluation process. Secondary outcomes include health outcomes (6-month vital status), as well as measures of the reach, adoption, and implementation of the intervention strategy.

New Developments in PCR-Based Diagnostics for Bacterial Pathogens Causing Gastrointestinal Infections—A Narrative Mini-Review on Challenges in the Tropics

“…If well-equipped laboratory infrastructure is scarce, automated cartridge-based PCR approaches provide an easy-to-implement solution for PCR in resource-poor tropical settings, as successfully proven by the rollout of GenXpert-(Sunnyvale, CA, USA-)based tuberculosis screening in sub-Saharan Africa [ 129 , 130 , 131 , 132 ]. Such assays are considerably easier to implement compared to traditional multiplex real-time PCR assays [ 133 ] and also available for gastroenteric pathogens [ 29 ].…”

Multicomponent strategy with decentralised molecular testing for tuberculosis in Uganda: a cost and cost-effectiveness analysis

“…XPEL-TB assessed whether providing decentralised point-of-care molecular testing using the GeneXpert Edge platform, in conjunction with streamlined clinical workflows and performance feedback via monthly report cards, would increase the number of people diagnosed with tuberculosis and reduce pre-treatment loss to follow-up, compared with routine care. 13 , 14 Ten health centres were randomised to receive this package, and had GeneXpert Edge systems installed onsite. The remaining ten centres were randomised to routine care, with SSM performed onsite and molecular Xpert testing performed at an off-site facility in accordance with national guidelines.…”

“…10 , 11 , 12 However, this strategy's cost-effectiveness has not been well documented using empirical data, an important consideration for decision makers charged with allocating scarce resources. The Xpert Performance Evaluation for Linkage to Tuberculosis Care (XPEL-TB) trial in Uganda 13 showed that, relative to centralised testing, the XPEL-TB strategy—a multicomponent strategy focused around decentralised molecular testing—improved case detection and treatment initiation. 14 As part of the XPEL-TB study, we collected empirical economic data in the context of the trial to evaluate the cost and cost-effectiveness of the XPEL-TB strategy versus routine tuberculosis testing (onsite SSM plus centralised Xpert testing using a hub-and-spoke model).…”

Is aggregated surveillance data a reliable method for constructing tuberculosis care cascades? A secondary data analysis from Uganda

“…The XPEL-TB Study was a cluster-randomized trial examining the effect of a multicomponent diagnostic strategy on the number of TB patients initiating treatment within 14 days of diagnosis. The intervention included on-site GeneXpert testing for TB and monthly feedback of quality metrics to staff [24][25][26].…”