Turning Off the Tap: Using the FAST Approach to Stop the Spread of Drug-Resistant Tuberculosis in the Russian Federation

Accuracy of digital chest x-ray analysis with artificial intelligence software as a triage and screening tool in hospitalized patients being evaluated for tuberculosis in Lima, Peru

Tuberculosis (TB) transmission in healthcare facilities is common in high-incidence countries. Yet, the optimal approach for identifying inpatients who may have TB is unclear. We evaluated the diagnostic accuracy of qXR (Qure.ai, India) computer-aided detection (CAD) software versions 3.0 and 4.0 (v3 and v4) as a triage and screening tool within the FAST (Find cases Actively, Separate safely, and Treat effectively) transmission control strategy. We prospectively enrolled two cohorts of patients admitted to a tertiary hospital in Lima, Peru: one group had cough or TB risk factors (triage) and the other did not report cough or TB risk factors (screening). We evaluated the sensitivity and specificity of qXR for the diagnosis of pulmonary TB using culture and Xpert as primary and secondary reference standards, including stratified analyses based on risk factors. In the triage cohort (n = 387), qXR v4 sensitivity was 0.91 (59/65, 95% CI 0.81-0.97) and specificity was 0.32 (103/322, 95% CI 0.27-0.37) using culture as reference standard. There was no difference in the area under the receiver-operating-characteristic curve (AUC) between qXR v3 and qXR v4 with either a culture or Xpert reference standard. In the screening cohort (n = 191), only one patient had a positive Xpert result, but specificity in this cohort was high (>90%). A high prevalence of radiographic lung abnormalities, most notably opacities (81%), consolidation (62%), or nodules (58%), was detected by qXR on digital CXR images from the triage cohort. qXR had high sensitivity but low specificity as a triage in hospitalized patients with cough or TB risk factors. Screening patients without cough or risk factors in this setting had a low diagnostic yield. These findings further support the need for population and setting-specific thresholds for CAD programs.

Accuracy of digital chest x-ray analysis with artificial intelligence software as a triage and screening tool in hospitalized patients being evaluated for tuberculosis in Lima, Peru

Introduction

Tuberculosis (TB) transmission in healthcare facilities is common in high-incidence countries. Yet, the optimal approach for identifying inpatients who may have TB is unclear. We evaluated the diagnostic accuracy of qXR (Qure.ai, India) computer-aided detection (CAD) software versions 3.0 and 4.0 (v3 and v4) as a triage and screening tool within the FAST (Find cases Actively, Separate safely, and Treat effectively) transmission control strategy.

Methods

We prospectively enrolled two cohorts of patients admitted to a tertiary hospital in Lima, Peru: one group had cough or TB risk factors (triage) and the other did not report cough or TB risk factors (screening). We evaluated the sensitivity and specificity of qXR for the diagnosis of pulmonary TB using culture and Xpert as primary and secondary reference standards, including stratified analyses based on risk factors.

Results

In the triage cohort (n=387), qXR v4 sensitivity was 0.91 (59/65, 95% CI 0.81-0.97) and specificity was 0.32 (103/322, 95% CI 0.27-0.37) using culture as reference standard. There was no difference in the area under the receiver-operating-characteristic curve (AUC) between qXR v3 and qXR v4 with either a culture or Xpert reference standard. In the screening cohort (n=191), only one patient had a positive Xpert result, but specificity in this cohort was high (>90%). A high prevalence of radiographic lung abnormalities, most notably opacities (81%), consolidation (62%), or nodules (58%), was detected by qXR on digital CXR images from the triage cohort.

Conclusions

qXR had high sensitivity but low specificity as a triage in hospitalized patients with cough or TB risk factors. Screening patients without cough or risk factors in this setting had a low diagnostic yield. These findings further support the need for population and setting-specific thresholds for CAD programs.

Feasibility of Find cases Actively, Separate safely and Treat effectively (FAST) strategy for early diagnosis of TB in Nepal: An implementation research

Introduction

Tuberculosis is one of the leading causes of death worldwide. Diagnosing TB in an early stage and initiating effective treatment is one of the best ways to reduce the burden of tuberculosis. Feasibility of Find cases Actively, Separate safely and Treat effectively (FAST) Strategy helps to improve the early diagnosis of tuberculosis cases among inpatient settings as well as out patient department patients and prevent TB transmission in hospital. This study aimed to assess the feasibility of the FAST strategy, organizational factors, technical factors, barriers and enablers for the proper implementation of the FAST strategy in Nepal.

Methods

A qualitative study was conducted from April 2019 to August 2019. Data was collected by using focus group discussion, key informant interviews, and client exit interviews. A retrospective research was conducted in different hospitals in Nepal where FAST strategy was implemented. The patients, health care workers, province, district, and National level stakeholders were interviewed. Thematic analysis was used to assess the feasibility as well as barriers and enablers of the FAST strategy.

Results

Study identified that the ‘current setting’ of implementation and service delivery arrangement at hospitals were not well arranged as per requirements. The research findings showed hospital ownership is crucial for mobilizing staff and proper space management inside hospitals. Study identified that unavailability of a separate room, limited capacity of GeneXpert machine, irregular supply of GeneXpert cartridge, and insufficient human resources for screening and counseling are the major barriers of FAST implementation in Nepal.

Conclusion

FAST strategy is feasible to implement in healthcare settings in Nepal although the technical and organizational factors should be managed to ensure effective function of the strategy as per the approach. Hospital ownership is essential to mobilize health workers, improve client flow system and proper space management for FAST services.

FAST tuberculosis transmission control strategy speeds the start of tuberculosis treatment at a general hospital in Lima, Peru

Objective:

To evaluate the effect of the FAST (Find cases Actively, Separate safely, Treat effectively) strategy on time to tuberculosis diagnosis and treatment for patients at a general hospital in a tuberculosis-endemic setting.

Design:

Prospective cohort study with historical controls.

Participants:

Patients diagnosed with pulmonary tuberculosis during hospitalization at Hospital Nacional Hipolito Unanue in Lima, Peru.

Methods:

The FAST strategy was implemented from July 24, 2016, to December 31, 2019. We compared the proportion of patients with drug susceptibility testing and tuberculosis treatment during FAST to the 6-month period prior to FAST. Times to diagnosis and tuberculosis treatment were also compared using Kaplan-Meier plots and Cox regressions.

Results:

We analyzed 75 patients diagnosed with pulmonary tuberculosis through FAST. The historical cohort comprised 76 patients. More FAST patients underwent drug susceptibility testing (98.7% vs 57.8%; OR, 53.8; P < .001), which led to the diagnosis of drug-resistant tuberculosis in 18 (24.3%) of 74 of the prospective cohort and 4 (9%) of 44 of the historical cohort (OR, 3.2; P = .03). Overall, 55 FAST patients (73.3%) started tuberculosis treatment during hospitalization compared to 39 (51.3%) controls (OR, 2.44; P = .012). FAST reduced the time from hospital admission to the start of TB treatment (HR, 2.11; 95% CI, 1.39–3.21; P < .001).

Conclusions:

Using the FAST strategy improved the diagnosis of drug-resistant tuberculosis and the likelihood and speed of starting treatment among patients with pulmonary tuberculosis at a general hospital in a tuberculosis-endemic setting. In these settings, the FAST strategy should be considered to reduce tuberculosis transmission while simultaneously improving the quality of care.

Preventing Transmission of Mycobacterium Tuberculosis-A Refocused Approach

Traditional tuberculosis (TB) infection control focuses on the known patient with TB, usually on appropriate treatment. A refocused, intensified TB infection control approach is presented. Combined with active case finding and rapid molecular diagnostics, an approach called FAST is described as a convenient way to call attention to the untreated patient. Natural ventilation is the mainstay of air disinfection in much of the world. Germicidal ultraviolet technology is the most sustainable approach to air disinfection under resource-limited conditions. Testing and treatment of latent TB infection works to prevent reactivation but requires greater risk targeting in both low- and high-risk settings.

Treatment as prevention and other interventions to reduce transmission of multidrug-resistant tuberculosis

Drug-resistant tuberculosis (DR-TB) represents a major programmatic challenge at the national and global levels. Only ∼30% of patients with multidrug-resistant TB (MDR-TB) were diagnosed, and ∼25% were initiated on treatment for MDR-TB in 2016. Increasing evidence now points towards primary transmission of DR-TB, rather than inadequate treatment, as the main driver of the DR-TB epidemic. The cornerstone of DR-TB transmission prevention should be earlier diagnosis and prompt initiation of effective treatment for all patients with DR-TB. Despite the extensive scale-up of Xpert^® MTB/RIF testing, major implementation barriers continue to limit its impact. Although there is longstanding evidence in support of the rapid impact of treatment on patient infectiousness, delays in the initiation of effective DR-TB treatment persist, resulting in ongoing transmission. However, it is also imperative to address the burden of latent drug-resistant tuberculous infection because it is estimated that many DR-TB patients will become infectious before seeking care and encounter various diagnostic delays before treatment. Addressing latent DR-TB primarily consists of identifying, treating and following the contacts of patients with MDR-TB, typically through household contact evaluation. Adjunctive measures, such as improved ventilation and use of germicidal ultraviolet technology can further reduce TB transmission in high-risk congregate settings. Although many gaps remain in our biological understanding of TB transmission, implementation barriers to early diagnosis and rapid initiation of effective DR-TB treatment can and must be overcome if we are to impact DR-TB incidence in the short and long term.

Reducing tuberculosis transmission: a consensus document from the World Health Organization Regional Office for Europe

Evidence-based guidance is needed on 1) how tuberculosis (TB) infectiousness evolves in response to effective treatment and 2) how the TB infection risk can be minimised to help countries to implement community-based, outpatient-based care.This document aims to 1) review the available evidence on how quickly TB infectiousness responds to effective treatment (and which factors can lower or boost infectiousness), 2) review policy options on the infectiousness of TB patients relevant to the World Health Organization European Region, 3) define limitations of the available evidence and 4) provide recommendations for further research.The consensus document aims to target all professionals dealing with TB (e.g TB specialists, pulmonologists, infectious disease specialists, primary healthcare professionals, and other clinical and public health professionals), as well as health staff working in settings where TB infection is prevalent.

What can National TB Control Programmes in low- and middle-income countries do to end tuberculosis by 2030?

The international community has committed to ending the tuberculosis (TB) epidemic by 2030. This will require multi-sectoral action with a focus on accelerating socio-economic development, developing and implementing new tools, and expanding health insurance coverage. Within this broad framework, National TB Programmes (NTPs) are accountable for delivering diagnostic, treatment, and preventive services. There are large gaps in the delivery of these services, and the aim of this article is to review the crucial activities and interventions that NTPs must implement in order to meet global targets and milestones that will end the TB epidemic. The key deliverables are the following: turn End TB targets and milestones into national measurable indicators to make it easier to track progress; optimize the prompt and accurate diagnosis of all types of TB; provide rapid, complete, and effective treatment to all those diagnosed with TB; implement and monitor effective infection control practices; diagnose and treat drug-resistant TB, associated HIV infection, and diabetes mellitus; design and implement active case finding strategies for high-risk groups and link them to the treatment of latent TB infection; engage with the private-for-profit sector; and empower the Central Unit of the NTP particularly in relation to data-driven supportive supervision, operational research, and sustained financing. The glaring gaps in the delivery of TB services must be remedied, and some of these gaps will require new paradigms and ways of working which include patient-centered and higher-quality services. There must also be fast-track ways of incorporating new diagnostic, treatment, and prevention tools into program activities so as to rapidly reduce TB incidence and mortality and meet the goal of ending TB by 2030.