Evidence for Tuberculosis in Individuals With Xpert Ultra "Trace" Sputum During Screening of High-Burden Communities.

BACKGROUND: "Trace" results on Xpert MTB/RIF Ultra ("Ultra"; Cepheid) -a molecular diagnostic test for tuberculosis (TB)-are often interpreted as an indication for TB treatment, but may also represent detection of nonviable bacilli or analytical error. In community-screening settings where individual TB risk is low, there is limited guidance on how to interpret Ultra-trace results. METHODS: We conducted systematic Ultra TB screening of adults and adolescents (≥15 years) in Kampala, Uganda, through door-to-door and event-based sputum collection. We enrolled individuals with trace-positive sputum for detailed clinical, radiographic, and microbiological (including 2 sputum cultures, repeat Ultra, and for people with HIV, urine lipoarabinomannan) evaluation, and compared those findings with similar evaluations in controls with Ultra-negative and Ultra-positive (non-trace) sputum. RESULTS: Of 21 957 people screened with Ultra, 211 (1.0%) tested positive, including 96 (46% of positives) with trace results. Of 92 people enrolled with trace-positive sputum; 12% (11/92) were HIV-positive and 14% (13/92) had prior TB. The prevalence of TB among participants with trace-positive sputum results was 14% (13/92) by culture, 24% (22/92) using broader microbiological criteria, and 26% (24/92) after accounting for clinical diagnosis. The prevalence of cough and of abnormal chest computed tomography (CT) findings were 32% and 26%, respectively, if Ultra-negative; 34% and 54% if trace-positive/non-microbiologically confirmed; 72% and 95% if trace-positive/microbiologically confirmed; and 71% and 93% if Ultra-positive (more than trace). CONCLUSIONS: Most individuals with trace-positive sputum in Ugandan communities did not have microbiologically confirmed TB but had more symptoms and chest CT abnormalities than people with Ultra-negative sputum.

Multicomponent Strategy with Decentralized Molecular Testing for Tuberculosis.

BACKGROUND: Effective strategies are needed to facilitate the prompt diagnosis and treatment of tuberculosis in countries with a high burden of the disease. METHODS: We conducted a cluster-randomized trial in which Ugandan community health centers were assigned to a multicomponent diagnostic strategy (on-site molecular testing for tuberculosis, guided restructuring of clinic workflows, and monthly feedback of quality metrics) or routine care (on-site sputum-smear microscopy and referral-based molecular testing). The primary outcome was the number of adults treated for confirmed tuberculosis within 14 days after presenting to the health center for evaluation during the 16-month intervention period. Secondary outcomes included completion of tuberculosis testing, same-day diagnosis, and same-day treatment. Outcomes were also assessed on the basis of proportions. RESULTS: A total of 20 health centers underwent randomization, with 10 assigned to each group. Of 10,644 eligible adults (median age, 40 years) whose data were evaluated, 60.1% were women and 43.8% had human immunodeficiency virus infection. The intervention strategy led to a greater number of patients being treated for confirmed tuberculosis within 14 days after presentation (342 patients across 10 intervention health centers vs. 220 across 10 control health centers; adjusted rate ratio, 1.56; 95% confidence interval [CI], 1.21 to 2.01). More patients at intervention centers than at control centers completed tuberculosis testing (adjusted rate ratio, 1.85; 95% CI, 1.21 to 2.82), received a same-day diagnosis (adjusted rate ratio, 1.89; 95% CI, 1.39 to 2.56), and received same-day treatment for confirmed tuberculosis (adjusted rate ratio, 2.38; 95% CI, 1.57 to 3.61). Among 706 patients with confirmed tuberculosis, a higher proportion in the intervention group than in the control group were treated on the same day (adjusted rate ratio, 2.29; 95% CI, 1.23 to 4.25) or within 14 days after presentation (adjusted rate ratio, 1.22; 95% CI, 1.06 to 1.40). CONCLUSIONS: A multicomponent diagnostic strategy that included on-site molecular testing plus implementation supports to address barriers to delivery of high-quality tuberculosis evaluation services led to greater numbers of patients being tested, receiving a diagnosis, and being treated for confirmed tuberculosis. (Funded by the National Heart, Lung, and Blood Institute; XPEL-TB ClinicalTrials.gov number, NCT03044158.).

Challenges with scale-up of GeneXpert MTB/RIF® in Uganda: a health systems perspective.

BACKGROUND: Many high burden countries are scaling-up GeneXpert® MTB/RIF (Xpert) testing for tuberculosis (TB) using a hub-and-spoke model. However, the effect of scale up on reducing TB has been limited. We sought to characterize variation in implementation of referral-based Xpert TB testing across Uganda, and to identify health system factors that may enhance or prevent high-quality implementation of Xpert testing services. METHODS: We conducted a cross-sectional study triangulating quantitative and qualitative data sources at 23 community health centers linked to one of 15 Xpert testing sites between November 2016 and May 2017 to assess health systems infrastructure for hub-and-spoke Xpert testing. Data sources included a standardized site assessment survey, routine TB notification data, and field notes from site visits. RESULTS: Challenges with Xpert implementation occurred at every step of the diagnostic evaluation process, leading to low overall uptake of testing. Of 2192 patients eligible for TB testing, only 574 (26%) who initiated testing were referred for Xpert testing. Of those, 54 (9.4%) were Xpert confirmed positive just under half initiated treatment within 14 days (n = 25, 46%). Gaps in required infrastructure at 23 community health centers to support the hub-and-spoke system included lack of refrigeration (n = 14, 61%) for sputum testing and lack of telephone/mobile communication (n = 21, 91%). Motorcycle riders responsible for transporting sputum to Xpert sites operated variable with trips once, twice, or three times a week at 10 (43%), nine (39%) and four (17%) health centers, respectively. Staff recorded Xpert results in the TB laboratory register at only one health center and called patients with positive results at only two health centers. Of the 15 Xpert testing sites, five (33%) had at least one non-functioning module. The median number of tests per day was 3.57 (IQR 2.06-4.54), and 10 (67%) sites had error/invalid rates > 5%. CONCLUSIONS: Although Xpert devices are now widely distributed throughout Uganda, health system factors across the continuum from test referral to results reporting and treatment initiation preclude effective implementation of Xpert testing for patients presenting to peripheral health centers. Support for scale up of innovative technologies should include support for communication, coordination and health systems integration.

Accuracy of C-Reactive Protein for Tuberculosis Detection in General-Population Screening and Ambulatory-Care Triage in Uganda.

Rationale: C-reactive protein (CRP) has demonstrated utility as a point-of-care triage test for tuberculosis (TB) in clinical settings, particularly among people with human immunodeficiency virus (HIV), but its performance for general-population TB screening is not well characterized. Objective: To assess the accuracy of CRP for detecting pulmonary TB disease among individuals undergoing community-based screening or presenting for evaluation of TB symptoms in Kampala, Uganda. Methods: We pooled data from two case-control studies conducted between May 2018 and December 2022 among adolescents and adults (⩾15 yr) in Kampala, Uganda. We conducted community-based screening for TB, regardless of symptoms. We enrolled people with Xpert MTB/RIF Ultra-positive (including trace) sputum results and a sample of people with Ultra-negative results. We also enrolled symptomatic patients diagnosed with TB and controls with negative TB evaluations from ambulatory care settings. Participants underwent further evaluation, including sputum culture, CRP, and HIV testing. We assessed the accuracy of CRP alone or with symptom screening against a bacteriologic reference standard. Our primary analysis evaluated the sensitivity and specificity of CRP at a cutoff of 5 mg/L. Diagnostic performance was summarized by calculating the area under the receiver operating curve (AUC). Results: In the community setting (n = 544), CRP ⩾ 5 mg/L had a sensitivity of 55.3% (95% confidence interval, 47.0-63.4%) and specificity of 84.7% (79.7-88.8%) for confirmed TB; AUC was 0.75 (0.70-0.79). Screening for CRP ⩾ 5 mg/L or positive symptoms increased sensitivity to 92.0% (86.4-95.8%) at the expense of specificity (57.1% [50.8-63.2%]). In the ambulatory care setting (n = 944), sensitivity of CRP ⩾ 5 mg/L was 86.7% (81.8-90.7%), specificity was 68.6% (64.8-72.2%), and AUC (0.84 [0.81-0.87]) did not differ significantly by HIV status. CRP ⩾ 5 mg/L was >90% sensitive among individuals with a medium or high semiquantitative Xpert result in both settings. Conclusions: Although CRP did not meet World Health Organization (WHO) TB screening benchmarks in the community, it demonstrated high specificity, and sensitivity was high among individuals with high sputum bacillary burden who are likely to be most infectious. In ambulatory care, estimated sensitivity and specificity were each within 4 percentage points of WHO benchmarks, with no meaningful difference in performance by HIV status.

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

BACKGROUND: Decentralised molecular testing for tuberculosis could reduce missed diagnoses and losses to follow-up in high-burden settings. The aim of this study was to evaluate the cost and cost-effectiveness of the Xpert Performance Evaluation for Linkage to Tuberculosis Care (XPEL-TB) study strategy, a multicomponent strategy including decentralised molecular testing for tuberculosis, in Uganda. METHODS: We conducted a costing and cost-effectiveness analysis nested in a pragmatic cluster-randomised trial of onsite (decentralised) versus hub-and-spoke (centralised) testing for tuberculosis with Xpert MTB/RIF Ultra (Xpert) in 20 community health centres in Uganda. We collected empirical data on the cost of the XPEL-TB strategy (decentralised Xpert testing, workflow redesign, and performance feedback) and routine tuberculosis testing (onsite smear microscopy with specimen transport for centralised Xpert testing) from the health system perspective. Time-and-motion studies were performed to estimate activity-based service costs. Cost-effectiveness was assessed as the incremental cost (2019 US$) per tuberculosis diagnosis and per 14-day treatment initiation. FINDINGS: The XPEL-TB study ran from Oct 22, 2018, to March 1, 2020. Effectiveness and cost-effectiveness outcomes were assessed from Dec 1, 2018, to Nov 30, 2019 and included 4867 women and 3139 men. On a per-test basis, the cost of decentralised ($20·46, range $17·85-25·72) and centralised ($18·20, range $16·58-24·25) Xpert testing was similar. However, decentralised testing resulted in more patients receiving appropriate Xpert testing, so the per-patient cost of decentralised testing was higher: $20·28 (range $17·68-25·48) versus $9·59 (range $7·62-14·34). The XPEL-TB strategy was estimated to cost $1332 (95% uncertainty range $763-5558) per incremental tuberculosis diagnosis and $687 ($501-1207) per incremental patient initiating tuberculosis treatment within 14 days. Cost-effectiveness was reduced in sites performing fewer than 150-250 tests annually. INTERPRETATION: The XPEL-TB strategy facilitated higher rates of Xpert testing for tuberculosis at a similar per-test cost and modest incremental cost per tuberculosis diagnosis and treatment initiation. Decentralised Xpert testing, with appropriate implementation supports, should be scaled up to clinics with sufficient testing volume to support a single-module device. FUNDING: The National Heart, Lung, and Blood Institute.

Readiness to implement on-site molecular testing for tuberculosis in community health centers in Uganda.

BACKGROUND: Newer molecular testing platforms are now available for deployment at lower-level community health centers. There are limited data on facility- and health worker-level factors that would promote successful adoption of such platforms for rapid tuberculosis (TB) testing and treatment initiation. Our study aimed to assess readiness to implement onsite molecular testing at community health centers in Uganda, a high TB burden country in sub-Saharan Africa. METHODS: To understand implementation readiness, we conducted a qualitative assessment guided by the Consolidated Framework for Implementation Research (CFIR) at 6 community health centers in central and eastern Uganda between February and April 2018. We conducted 23 in-depth, semi-structured interviews with health workers involved in TB care at each health center to assess TB-related work practices and readiness to adopt onsite molecular testing using the GeneXpert Edge platform. Interviews were transcribed verbatim and coded for thematic analysis. RESULTS: Participants (N=23) included 6 nurses/nursing assistants, 6 clinicians, 6 laboratory directors/technicians, 1 medical officer, 2 health center directors, and 2 other health workers involved in TB care. Health workers described general enthusiasm that on-site molecular testing could lead to greater efficiencies in TB diagnosis and treatment, including faster turn- around time for TB test results, lack of need for trained laboratory technicians to interpret results, and reduced need to transport sputum specimens to higher level facilities. However, health workers also expressed concerns about implementation feasibility. These included uncertainty about TB infection risk, safety risks from disposal of hazardous waste, a lack of local capacity to provide timely troubleshooting and maintenance services, and concerns about the security of GeneXpert devices and accessories. Health workers also expressed the need for backup batteries to support testing or charging when wall power is unstable. CONCLUSION: Our study generated a nuanced understanding of modifiable contextual barriers and led to direct revisions of implementation strategies for onsite molecular testing. The findings highlight that novel diagnostics should be implemented along with health system co-interventions that address contextual barriers to their effective uptake. Pre-implementation assessment of stakeholder perspectives, collaborative work processes, and institutional contexts is essential when introducing innovative technology in complex health care settings.

Design and execution of a public randomization ceremony to enhance stakeholder engagement within a cluster randomized trial to improve tuberculosis diagnosis in Uganda.

Public randomization ceremonies have been proposed as a strategy to strengthen stakeholder engagement and address concerns and misconceptions associated with trial randomization. However, there are few published examples that describe how to conduct a public randomization ceremony with meaningful stakeholder engagement or how such ceremonies impact stakeholder perceptions about randomization and the randomization process. Cluster randomization for the GeneXpert Performance Evaluation for Linkage to Tuberculosis Care (XPEL-TB) trial was conducted at a public randomization ceremony attended by 70 stakeholders in Kampala, Uganda. Presentations given by the Acting Assistant Commissioner from the Uganda National Tuberculosis and Leprosy Programme and trial investigators emphasized how the trial aimed to further national TB goals, as well as how stakeholders contributed to the intervention design. The purpose and process of randomization were described using simple text and visuals. Randomization was an interactive activity that required participation of stakeholders from each trial site. A survey administered to stakeholders at the end of the ceremony suggested high comprehension of randomization (98%), trust in the randomization process (96%), and satisfaction with randomization outcomes (96%). Public randomization ceremonies should be considered more routinely to engage stakeholders in and address potential concerns about the fairness and impartiality of the randomization process for community-based trials.

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

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 cartridge-based 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. DISCUSSION: The design elements and implementation approach for the XPEL-TB trial were intentionally selected to minimize disruptions to routine care procedures, with the goal of limiting their influence on key primary and secondary outcomes. Trial findings may result in increased support and funding for rapid, onsite molecular testing as the standard-of-care for all patients being evaluated for TB. TRIAL REGISTRATION: US National Institutes of Health's ClinicalTrials.gov, NCT03044158. Registered 06 February 2017. Pan African Clinical Trials Registry, PACTR201610001763265. Registered 03 September 2016.

Feasibility of a short message service (SMS) intervention to deliver tuberculosis testing results in peri-urban and rural Uganda.

BACKGROUND: Pre-treatment loss to follow-up is common for patients diagnosed with tuberculosis (TB) in high-burden countries. Delivering test results by Short-Messaging-Service (SMS) is increasingly being considered as a solution, but there is limited information about its feasibility as a public health tool in low resourced settings. OBJECTIVE: We sought to assess the feasibility of utilizing SMS technology to deliver TB test results during routine TB diagnostic evaluation in Uganda. METHODS: We conducted a single arm interventional pilot study at four community health centers in Uganda that referred sputum samples to a district hospital for GeneXpert-MTB/RIF (Xpert) testing (Cepheid, USA). Using existing GxAlert-software (SystemOne,USA), we set up an automated SMS platform to send Xpert results to patients and referring health centers. We assessed each step of the SMS delivery cascade for consecutive patients who presented to these four community health centers between December 2015 and March 2016 and underwent Xpert testing. RESULTS: Of 233 patients enrolled, 161 (69%) had phone numbers recorded on individual Xpert referral forms. Phone numbers were entered into Xpert device software in the correct format for 152 (94%) patients. GxAlert-software generated an automated SMS reporting Xpert results for 151 (99%) patients and delivered it successfully to mobile phone service providers for 145/151 (96%). Of the 123 patients reached by phone to determine receipt of test results, 114 (93%) confirmed SMS receipt. SMS-based delivery of Xpert results was verified for 114/233 (49%) patients overall. In contrast, phone calls to health centers confirmed that health centers received messages for 222/233 (95%) patients. CONCLUSION: Reporting Xpert results via automated SMS is technically feasible and results in approximately half of patients receiving their test results immediately. Additional research should be done to address process inefficiencies in order to maximize impact of this technology and link its successful utilization to improved patient outcomes.

Quality of care for patients evaluated for tuberculosis in the context of Xpert MTB/RIF scale-up.

RATIONALE: Many high-burden countries are scaling-up Xpert MTB/RIF using a hub-and-spoke model. We evaluated the quality of care for patients undergoing TB evaluation at microscopy centers (spokes) linked to Xpert testing sites (hubs) in Uganda. OBJECTIVES: To characterize the extent to which patients were receiving care in accordance with international and national guidelines. METHODS: We conducted a prospective cohort study of all adults with presumptive pulmonary TB at 24 health centers linked to Xpert testing sites. Health center staff photographed TB registers, and uploaded photos to a secure server bi-weekly. We assessed the proportion of patients (1) initiating testing; (2) completing testing; and (3) treated for confirmed TB within 14 days. MEASUREMENTS AND MAIN RESULTS: Between January to December 2017, 6744 patients underwent evaluation for pulmonary TB. Only 1316 patients had sputum referred for Xpert testing, including 1075/3229 (33.3%) people living with HIV and 241/3515 (6.9%) without HIV. Of 119 patients confirmed to have TB by Xpert testing, 44 (36%) did not initiate treatment. There were significant losses along the entire diagnostic cascade of care, with only 5330/6744 (79.0%) patients having samples referred for sputum-based testing, 2978/5330 (55.9%) patients completing recommended testing if referred, and 313/418 (74.9%) patients initiating treatment within 14 days if confirmed to have TB. CONCLUSIONS: Although coverage of Xpert testing services across Uganda is high, the quality of care delivered to patients undergoing TB evaluation remains poor. Further research is needed to identify health system interventions to facilitate uptake of Xpert testing and high-quality care.