The impact, effectiveness and outcomes of targeted screening thresholds for programmatic latent tuberculosis infection testing in HIV.

BACKGROUND: Screening and treatment for latent tuberculosis infection (LTBI) are key for TB control. In the UK, the National Institute for Health and Care Excellence (NICE) and the British HIV Association (BHIVA) give conflicting guidance on which groups of people with HIV (PWH) should be screened, and previous national analysis demonstrated heterogeneity in how guidance is applied. There is an urgent need for a firmer clinical effectiveness evidence base on which to build screening policy. METHODS: We conducted a systematic, programmatic LTBI-screening intervention for all PWH receiving care in Leicester, UK. We compared yields (percentage IGRA positive) and number of tests required when applying the NICE and BHIVA testing strategies, as well as strategies targeting screening by TB incidence in patients' countries of birth. RESULTS: Of 1053 PWH tested, 118 were IGRA-positive (11.2%). Positivity was associated with higher TB incidence in country-of-birth [adjusted odds ratio, 50-149 cases compared with <50 cases/100 000: 11.6; 95% confidence interval (CI) 4.79-28.10)]. There was high testing uptake (1053/1069, 98.5%). Appropriate chemoprophylaxis was commenced in 100 of 117 (85.5%) patients diagnosed with LTBI, of whom 96 of 100 (96.0%) completed treatment. Delivering targeted testing to PWH from countries with TB incidence greater than 150 per 100 000 population or any sub-Saharan African country, would have correctly identified 89.8% of all LTBI cases while cutting tests required by 46.1% compared with NICE guidance, performing as well as BHIVA 2018 guidance. CONCLUSION: Targeting screening to higher risk PWH increases yield and reduces the number requiring testing. Our proposed 'PWH-LTBI streamlined guidance' offers a simplified approach, with the potential to improve national LTBI-screening implementation.

Latent tuberculosis screening and treatment in HIV: highly acceptable in a prospective cohort study.

Background: People living with HIV (PLWH) are at increased risk of re-activation of latent tuberculosis infection (LTBI). Although UK and international guidelines identify this group as a priority for LTBI screening and treatment, data on attitudes of PLWH to this policy recommendation are lacking. Methods: A five-point, Likert-style questionnaire was administered to PLWH to assess views and intentions towards accepting LTBI screening and treatment. Subsequent interferon-γ release assay (IGRA) testing was offered, and chemoprophylaxis if required. Influencing demographic and psychological associations with planned, and actual, testing and treatment uptake were assessed using multivariable logistic regression. Results: 444 out of 716 (62%) patients responded. 417 out of 437 (95.4%) expressed intention to accept LTBI testing. The only significant association was the perceived importance of testing to the individual (adjusted odds ratio (aOR) 8.98, 95% CI 2.55-31.67). 390 out of 393 (99.2%) accepted appropriate IGRA screening; 41 out of 390 (10.5%) were positive. 397 out of 431 (92.1%) expressed intention to accept chemoprophylaxis, associated with perceived importance of treatment (aOR 3.52, 95% CI 1.46-8.51), a desire to have treatment for LTBI (aOR 1.77, 95% CI 0.99-3.15) and confidence in taking treatment (aOR 3.77, 95% CI 1.84-7.72). Of those offered chemoprophylaxis, 36 out of 37 (97.3%) accepted and 34 out of 36 (94.4%) completed treatment. There were no correlates with actual screening acceptance. Conclusions: LTBI is common amongst PLWH, highlighting the importance of robust screening and treatment programmes. This study shows that screening and treatment for LTBI is highly acceptable to PLWH and provides strong, objective evidence for policy-makers developing guidelines in this cohort.

Tuberculosis incidence in country of origin is a key determinant of the risk of active tuberculosis in people living with HIV: Data from a 30-year observational cohort study.

INTRODUCTION: People living with HIV (PLWH) are at high risk of active tuberculosis (TB) but this risk in the era of antiretroviral treatment (ART) remains unclear. It is critical to identify the groups who should be prioritised for latent TB (LTBI) screening. In this study we identified the risk factors associated with developing incident TB disease, by analysing a 30-year observational cohort. METHODS: We evaluated PLWH in Leicester, UK, between 1983 and 2017 to ascertain those who developed active TB and the timing of this in relation to HIV diagnosis; whether before, concurrently with, or more than 3 months after the diagnosis of HIV (incident TB). Predictors of incident TB were ascertained using Cox proportional hazards models. RESULTS: In all, 325 out of 2158 (15.1%) PLWH under care had had active TB; 64/325 (19.7%) prior to HIV diagnosis, 161/325 (49.5%) concurrently with/within 3 months of HIV diagnosis and 100/325 (30.8%) had incident TB. Incident TB risk was 4.57/1000 person-years. Increased TB incidence in the country of birth was associated with an increased risk of developing incident TB [50-149/100 000 population, adjusted hazard ratio (AHR) = 3.10, 95% CI: 0.94-10.20; 150-249/100 000 population, AHR = 7.14, 95% CI: 3.46-14.74; 250-349/100 000 population, AHR = 5.90, 95% CI: 2.32-14.99; ≥ 350/100 000 population, AHR = 3.96, 95% CI: 1.39-11.26]. CONCLUSIONS: Tuberculosis risk remains high among PLWH and is related to TB incidence in the country of birth. Further work is required to determine whether specific groups of PLWH should be targeted for programmatic LTBI screening, and whether it will result in high uptake and completion of chemoprophylaxis and is cost-effective for widespread implementation.

Maximising the opportunity of a self-administration outpatient parenteral antimicrobial therapy pathway.

BACKGROUND: The University Hospitals of Leicester NHS Trust outpatient parenteral antimicrobial therapy (OPAT) service has expanded rapidly with more nurse-led direction. AIMS: A retrospective study between 1 July 2014 and 31 December 2019 was undertaken to assess the impact of OPAT expansion on beds released for further utilisation, clinical outcomes, adverse vascular access device (VAD) outcome, and self- and family-administered parenteral antimicrobial therapy. METHOD: Data were extracted from the OPAT Patient Management System and from a patient questionnaire survey. FINDINGS: 1084 completed patient episodes were recorded in 958 patients, rising from 39 episodes in 2014 to 265 in 2019. The number of beds released for further utilisation correspondingly rose from 828 in 2014 to 8462 in 2019. The proportion of patients/family members trained to self-administer rose from 25% to 75%, with clinical cure/improvement of infection remaining high at between 84.6% and 92.8% of patients annually. Serious adverse VAD events remained low throughout. The patient response was generally positive. CONCLUSION: Nurse empowerment within OPAT can lead to significant improvements and patient benefits, while maintaining clinical outcomes.

Health economic analyses of latent tuberculosis infection screening and preventive treatment among people living with HIV in lower tuberculosis incidence settings: a systematic review.

Introduction: In lower tuberculosis (TB) incidence countries (<100 cases/100,000/year), screening and preventive treatment (PT) for latent TB infection (LTBI) among people living with HIV (PLWH) is often recommended, yet guidelines advising which groups to prioritise for screening can be contradictory and implementation patchy. Evidence of LTBI screening cost-effectiveness may improve uptake and health outcomes at reasonable cost. Methods: Our systematic review assessed cost-effectiveness estimates of LTBI screening/PT strategies among PLWH in lower TB incidence countries to identify model-driving inputs and methodological differences. Databases were searched 1980-2020. Studies including health economic evaluation of LTBI screening of PLWH in lower TB incidence countries (<100 cases/100,000/year) were included. Study quality was assessed using the CHEERS checklist. Results: Of 2,644 articles screened, nine studies were included. Cost-effectiveness estimates of LTBI screening/PT for PLWH varied widely, with universal screening/PT found highly cost-effective by some studies, while only targeting to high-risk groups (such as those from mid/high TB incidence countries) deemed cost-effective by others. Cost-effectiveness of strategies screening all PLWH from studies published in the past five years varied from US$2828 to US$144,929/quality-adjusted life-year gained (2018 prices). Study quality varied, with inconsistent reporting of methods and results limiting comparability of studies. Cost-effectiveness varied markedly by screening guideline, with British HIV Association guidelines more cost-effective than NICE guidelines in the UK. Discussion: Cost-effectiveness studies of LTBI screening/PT for PLWH in lower TB incidence settings are scarce, with large variations in methods and assumptions used, target populations and screening/PT strategies evaluated. The limited evidence suggests LTBI screening/PT may be cost-effective for some PLWH groups but further research is required, particularly on strategies targeting screening/PT to PLWH at higher risk. Standardisation of model descriptions and results reporting could facilitate reliable comparisons between studies, particularly to identify those factors driving the wide disparity between cost-effectiveness estimates. Registration: PROSPERO CRD42020166338 (18/03/2020).

Prevention of perinatal hepatitis B virus transmission: are we following guidelines?

It is recommended that infants born to women with hepatitis B infection should have serological review following completion of a four dose vaccination schedule. A review was undertaken on 102 neonates who received hepatitis B immunoglobulin to ascertain the proportion that were fully immunised and then followed up. Of the 66 infants for whom data were available, 65 (98.5%) had appropriately received four doses of hepatitis B vaccine in infancy and a further child had received three doses. Only 19/66 (29%; 95%CI: 18-41%) infants had documented follow-up serology results, one of whom was infected and one of whom was immune through clearance of infection. All children who had no serology documented were traced and offered testing in primary care. Our results demonstrate that although adherence to the vaccination schedule in this group of infants was good, mechanisms for ensuring that infants receive serology testing need to be strengthened.

Latent tuberculosis infection screening and treatment in HIV: insights from evaluation of UK practice.

Latent TB infection (LTBI) screening and treatment in HIV-positive individuals in the UK is advocated by the British HIV Association (BHIVA) and National Institute for Health and Care Excellence (NICE), although each recommends differing strategies. We undertook an evaluation of UK practice, relating the responses to the local HIV/TB disease burden. 162 of 188 (86%) UK geographical areas responded; only 93/162 (57.4%) offer LTBI testing with considerable heterogeneity in practice, and no difference in HIV/TB burden between areas offering testing and those who do not. Only 33/93 (35.5%) and 6/93 (6.5%) reported full compliance with BHIVA and NICE guidance respectively. A uniform national guideline is required.