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Physicians and clinical employees at a children's hospital were surveyed to compare their tuberculosis (TB) screening and immunization statuses. Failure to offer screening and immunization services to non-employee physicians was associated with lower rates of reported immunity to several vaccine-preventable diseases and with markedly lower rates of TB screening.

Cheng-Rang Li, Qiu-Xia Mao, Min Chen, Wei-Xue Jia, Xu Yao, Su-Ying Feng, Hong Jia, Juan-Qin Gong, Xue-Yuan Yang Institute of Dermatology, Chinese Academy of Medical Sciences & Peking Union Medical College, Nanjing, Jiangsu, People’s Republic ofChina Background: TNF-α plays a key role in host defense against mycobacterial infection, and patients receiving TNF-α blocker treatment have increased susceptibility to tuberculosis disease. In the People’s Republic of China, an intermediate tuberculosis-burden country, the latent tuberculosis infection (LTBI) risk in patients with psoriasis who are treated with etanercept, the safest kind of TNF-α blocker, is unknown.Objectives: This study reports the LTBI risk in patients with psoriasis after etanercept treatment and aims to answer the question of how often rescreening for LTBI should be done in order to reduce active tuberculosis infection of patients and further reduce the incidence of active tuberculosis disease.Patients and methods: This retrospective review evaluated patients with moderate-to-severe chronic plaque psoriasis between 2009 and 2013. All patients were excluded tuberculosis infection and received etanercept 25mg twice weekly, then the patients were checked for LTBI 3months after etanercept treatment to observe the incidence of LTBI and assess the need for rescreening for LTBI every 3months.Results: We retrospectively analyzed 192 patients with psoriasis with moderate-to-severe chronic plaque whose tuberculin skin test and chest X-rays were negative and who received etanercept 25mg twice weekly. Eighteen of them were excluded because they received less than 3months of etanercept therapy. After treatment with etanercept, four patients were found to have LTBI.Conclusion: In this study, the incidence of LTBI after 3months was four in 192 (2.1%), which is higher than the annual incidence of LTBI in the People’s Republic of China (0.72%), so LTBI could be expected to occur within 3months in psoriasis patients on etanercept. Periodic screening for LTBI in the therapy course, as well as before initiating treatment, is necessary in those patients who use a TNF-α blocker. We recommend rescreening for LTBI every 3months. Keywords: TNF receptor, TNFR, fusion protein, treatment, LTBI, TB screening

Background: We obtained estimates of the incidence of tuberculosis (TB) among patients receiving HIV Treatment. We also modeled the relationship between incident TB and change in CD4 count over the follow-up period. Methods: We analyzed the incidence of TB over 10 years from initiation of HIV treatment among 345 HIV treatment-naοve persons, who were enrolled in a cohort in Kano, Nigeria. We used Generalized Estimating Equation [GEE] to identify determinants of TB incidence and model the relationship between the occurrences of TB with change in CD4 count over the follow-up period. We created Kaplan-Meier curves stratified by anti-retroviral therapy (ART) treatment failure status to examine the effect of first line ART treatment failure on occurrence of TB. Result: During the 10-year period, 47(13.62%) had TB [incidence was 7.43 per (1,000) person year)]. It is associated with decreasing age (OR = 0.98), female gender (OR = 0.83), being on first line ART other than AZT (OR = 0.87), poor adherence (OR = 1.25), change in ART regimen (OR = 2.3) and ART treatment failure (OR = 1.51). Odds of TB occurrence was also associated with CD4 increment at 10 years (OR = 0.99). Those with TB/HIV co-infection tend to have statistically significant shorter time to failing first line ART regimen compared to those with HIV infection alone. Conclusion: There was high incidence of TB in the studied HIV cohort with a deleterious effect on the outcome of ART treatment. There is need for early TB screening and re-screening among all HIV patients.

Reactivation of tuberculosis (TB) is a major concern during treatment with TNF inhibitors.1 Different guidelines to detect active and latent TB have been recommended in various countries before starting treatment with these drugs. There is evidence that their application has led to a significant reduction in the number of cases of TB,2 but we do not know which is the most cost effective strategy. In our department 69 consecutive patients with rheumatoid arthritis (n = 53), ankylosing spondylitis (n = 10), and psoriatic arthritis (n = 6) considered for treatment with TNF inhibitors …

In 2004, two employees in a skilled nursing facility developed active pulmonary tuberculosis (TB). Both employees were purified protein derivative (PPD) test positive for more than 10 years before developing the disease. Four employees converted to positive PPD status during the exposure investigation—two at baseline and two at the 12-week follow up. No additional cases of active TB were found. Several changes and additions have been made to the TB screening protocol after these two index cases were discovered.

Background The proportion of tuberculosis (TB) cases diagnosed among residents of correctional facilities in Arizona increased from 2.7% in 1993 to 8.0% in 2000, while the national average remained at approximately 4%. The purpose of this study was to determine the proportion of TB cases in Maricopa County, Arizona with a history of incarceration in the local county jail, and to describe missed opportunities for the prevention and early detection of active TB cases in this population. Methods A cross-match was used to identify persons reported to have TB in Maricopa County in 1999 and 2000 who also had a history of incarceration in the county jail. Jail medical records of cases were reviewed to determine if they had been screened for TB while incarcerated and the type of screening received. TB isolates for cases who had been in jail were genotyped using IS6110 restriction fragment-length polymorphism (RFLP) with secondary spoligotyping. Results Nearly one quarter (24.3%) of TB cases had a history of incarceration in the county jail. Most (82.8%) received no TB screening while in jail. Of 34 cases with available isolates, six shared a single genotype by RFLP and spoligotyping. Conclusions Increased screening and treatment of latent TB infection in jails might assist with TB control in the community.

A series of 3- or 4-phenyl-1,8-naphthyridine derivatives variously substituted in the positions 2, 6 and 7 were synthesized and evaluated for in vitro evaluation for their antimycobacterial activity as part of a TAACF TB screening program under the direction of the US National Institute of Health, NIAID division. Several compounds showed an interesting activity when tested at a concentration of 6.25 μg/ml against Mycobacterium tuberculosis H37Rv and in particular compounds 2a, 4a,d, 8a,d and 8i, exhibit a % inhibition from 91 to 99. Among these, compounds 2a, 8a and 8d appeared to have a good activity with minimum inhibitory concentrations (MICs) of 6.25 μg/ml. On the basis of the biological results, the most effective substituent in position 2 or 7 seems to be the piperidinyl group. The introduction of a morpholinyl group either in position 2 or 7 of the heterocycle ring caused a decrease in activity. The 1,8-naphthyridine derivatives were also tested in vitro for their antimicrobial activity against Staphylococcus aureus as Gram-positive bacteria and Escherichia coli as Gram-negative bacteria.

In support of the urgent need for improvements to new entrant TB screening,1 which must encourage the diagnosis of both active and latent forms of TB, we would like to offer two audits of new entrant screening from an area with a low TB incidence (4.3/100 000).2 In 2006, we audited 29 new entrant referrals, all of whom had a chest x-ray reported by the Port Health Control Unit at Heathrow Airport as ‘abnormal’ (predominantly hilar calcification).3 Of the 29 referrals, …

Tuberculosis (TB) remains the leading cause of death in the world from a single infectious disease, and the threat is becoming more critical with the spread of multi-drug resistant Tuberculosis (MDR-TB). TB detection, and susceptibility testing for drug resistant strain identification, is advancing with the development of Luciferase Reporter Mycobacteriophages (LRM). LRM will emit visible light at very low intensity when in the presence of live mycobacteria cells such as Tuberculosis strains. InterScience, Inc., together with its collaboration, is developing a highly sensitive, real-time digital detection system for the analysis of luminescent assays. Recent advances in system sensitivity, design, and implementation, as well as preliminary results of the development of individual test cartridges, will be presented. The ultimate goal of this work is to provide a versatile luminescence detection tool for widespread research and clinical applications.

There has been a rise in tuberculosis (TB) cases in the United States and there is a potent link between human immunodeficiency virus (HIV) and tuberculosis. In New York City it is estimated that 40% of the 200,000 injecting drug users are infected with HIV. In addition, the tuberculosis case rate is approximately four times the national average, and one third of these cases occurred in those persons infected with HIV. Drug users have a high prevalence of latent tuberculous infection and are at high risk for progression to active tuberculosis. Drug users are at high risk for both HIV and TB. Although studies have shown the value of incorporating TB services into drug treatment programs, the majority of drug users in the United States are not in drug treatment. We have been evaluating the feasibility of conducting TB screening and directly observed TB preventive therapy for active injecting drug users at a syringe exchange program in New York City. This paper describes issues relating to the implementation of the TB screening program and discusses general and operational issues relevant to integrating medical and public health programs into existing programs serving drug using individuals.

Introduction and Objectives NICE (2011) and the Department of Health (2007) provide guidance for occupational health departments for TB clearance in healthcare workers. Previous work from the London Consortium of Occupational Health Providers (LCOHPS) shows a marked variation in practice, notably in the criteria for defining high risk individuals. The length of time in the UK for an individual from a high TB endemic area (defined as an incidence of 40 per 100,000 or greater) to be considered as low risk ranges from 6 months to >5 years. We performed a retrospective study of new trust employees to see if changing the definition of a high risk individual would impact on the effectiveness of our screening programme. Methods We performed a retrospective study of 40 new employees at our trust between 2008 and 2012. Cases were selected on the basis of a positive QuantiFERON-TB Gold test at occupational health screening. Demographic data, including date of UK entry, were collected and analysed. Results Results are summarised in Table 1. Conclusions Changing the definition of a high risk individual by reducing the cut-off time since entry to the UK may have both financial and time-saving consequences. However, our data show that a significant proportion of healthcare workers with latent TB infection, and in some cases active TB infection, would be missed by reducing the cut-off to 1 year. Screening of healthcare workers is an important aspect in the prevention and control of TB. Reducing the effectiveness of this screening exposes patients to increased risk. In view of these data, we would not recommend reducing the cut-off time for the definition of a high risk individual to less than 5 years.

Introduction Best practise guidelines recommend that all patients starting Anti-TNF therapies should be pre-screened and vaccinated to reduce risk of opportunistic infections (ECCO guidelines 2009) and should be counselled re potential risks and benefits of treatments. Aims/Background To review documentation of anti-TNF therapy information provision and compliance with ECCO guidelines in prevention of opportunistic infections. Method We reviewed retrospectively the notes of all patients receiving infliximab therapy between Sep 2009 and Sep 2012 in BSH GI unit, Cork. Results 327 no of infusions was given to 39 patients (16 crohns/23 UC, M:F ratio 21:18) over study period. Discussion re treatment risks was clearly documented in 32/37(86%) patients, in 84% cases by IBD specialist nurse. Screening for opportunistic infections was incomplete. TB screening was undertaken in 100% (37/37) of cases but HIV testing was not routinely undertaken. 65%(24/37) patients had Hep B immunity status assessed but none were referred for vaccination programme. Varicella immunity was checked in 46% (17/37) patients, 2/17 (11.8%) patients non-immune! New tick-box proforma designed. Conclusion Rolling out of new guidelines which encorporate new practise is challenging and difficult to coordinate. In an effort to standardise approach we have designed a tick box proforma to use as part of our initial assessment of IBD patients. Our aim is to screen all patients at point of diagnosis of illness rather than at point of prescribing therapy so that vaccination can be coordinated when necessary in anticipation of requirement of therapies. Further studies will be required to look at success of this measure.

Background The accuracy of screening tests for latent tuberculosis infection (LTBI) such as TST and IGRAs and their agreement are varied according to study. Objectives We conducted meta-analysis on the positivity of LTBI screening tests and the level of agreement between them in the patients prior to use of anti-TNF agents. Then, we further analyzed the difference in agreement according to underlying rheumatic diseases and the prevalence of TB in each country. Methods OVID-MEDLINE, EMBASE, and Cochrane Library were searched for LTBI screening in patients with rheumatic diseases, including RA, AS, JIA, and PsA, through Nov 21st 2012. Among 135 literatures retrieved, 18 English original research articles were selected excluding non-FDA approved method, non-rheumatic disease(e.g. IBS, autoimmune diseases), and screenings after TNF-alpha inhibitor use. Heterogeneity was evaluated using the Cochran Q statistic. A random effect model was constructed in STATA 10®. Results In the pooled analysis, 4764 patients across all rheumatic diseases underwent both TST and one of IGRAs (4334 patients measured by QFT-GIT, and 711 by TSPOT) prior to use of anti-TNF agents. The positivity of TST (>5mm), TSPOT, and QFT-GIT among all patients were estimated as 34.7% [95% CI: 25.7-43.6], 16.1% [7.0-25.1], and 20.7% [14.8-26.6], respectively. The percent agreement between TST and QFT-GIT was 69.8% [64.3-75.3]. In low-to moderate endemic subjects (n=854), positive rate of TST, TSPOT, and QFT-GIT were35.6% [23.3-47.9], 15.5%[10.1-20.8], and 17.5% [9.5-25.5], wherease those of high endemic subjects (n=1010) were 33.6% [24.2-43.0], 23.9% [12.6-38.8], and 30.5% [23.6-37.3], respectively. Percent agreement between TST and QTF-GIT was lower in low-to-moderate endemic area than high endemic area (66.1% [56.5-75.6] vs. 72.7% [65.8-79.6]). In RA subjects (n=1073 patients of 8 studies), the positivity of TST, TSPOT, and QFT-GIT was 31.3% [25.0-37.6], 22.2% [3.0-41.4] and 27.3% [20.1-34.6]. In AS patients (n=317 patients of 3 studies; all high endemics), the positivity of TST, and QFT-GIT was 56.8% [35.0-78.7], and 26.3% [13.5-39.2], and agreement between TST and QFT-GIT was 54.9% [43.9-65.9]. Only sub-analyses by underlying diseases presented non-heterogeneities across literatures measured by Q statistics. Conclusions Among patients with rheumatic diseases, the screening results of TST and IGRAs are inconsistent across the underlying disease and endemic area. Specifically, a lower level of agreement between TST and IGRAs was found among patients with JIA and AS than RA population. Also, populations originated from low-to-moderate endemic regions, presented more disagreements, mainly due to similar positive rates of TST with lower rates by IGRAs, than patients of high endemic origins. It suggests different strategies are needed for each patient group to detect LTBI in clinical settings considering endemic origins. Disclosure of Interest None Declared

Introduction The effect of using a borderline zone for the interpretation of the interferon-γ release assay (IGRA) on the prediction of progression to active tuberculosis (TB) in healthcare workers (HCW) is analysed. Methods Data from a published study on TB screening in Portuguese HCW is reanalysed using a borderline zone for the interpretation of the IGRA. Testing was performed with the QuantiFERON-TB Gold In-Tube (QFT). The borderline zone for the QFT was defined as interferon (INF) in QFT ≥0.2 to Results The cohort comprised 2,884 HCW with a QFT that could be interpreted. In 1,780 (61.7%) HCW, the QFT was 0.7 IU/mL in 763 (26.3%) HCW. Fifty-seven HCW had a TB in their medical history, eight had a TB at the time of screening and progression to active TB was observed in four HCW. Two out of eight HCW (25%) with active TB at the time of screening had a QFT result falling into the borderline zone. One out of four HCW (25%) who progressed towards active TB after being tested with QFT had QFT results falling into the borderline zone. A second IGRA was performed in 1,199 HCW. In total, 292 (24.4%) HCW had at least one of the two IGRA results pertaining to the borderline zone. Conclusion Using a borderline zone for the QFT from 0.2 to 0.7 IU/mL should be administered with care, as active TB as well as progression to active TB might be overlooked. Therefore, the borderline zone should be restricted to populations with a low TB risk only.

Objectives: To describe the epidemiology of foreign-born tuberculosis (TB) cases in Los Angeles County and to evaluate current TB screening and follow-up of immigrants and refugees (I&R) to the USA. Design: Retrospective analysis of the Los Angeles County TB registry between October 1992 and December 1994. We matched all cases who entered the USA during fiscal year 1993 (FY93) with a database from the tracking system of I&R with suspected TB. Results: Foreign-born persons accounted for 64% of all reported TB cases. Half were born in Mexico or Central America. Standardized incidence rates were 3–5 times higher than those of US-born persons for Mexicans and Central Americans, 6–7 times higher for North-east Asians, and 10–15 times higher for Southeast Asians. Among foreign-born cases who arrived during FY93, 5% of the Mexicans and Central Americans, 48% of the North-east Asians and 67% of the South-east Asians were registered by the tracking system. Conclusion: Mexicans and Central Americans accounted for the majority of cases but had a lower incidence of TB than Asians. The current screening procedures identify a large proportion of cases among recently arrived South-east Asians, but contribute little to the control of TB among Mexicans and Central Americans.

Background Tuberculosis (TB) notifications in the UK continue to rise due to disease in the foreign-born immigrant population. UK guidelines on immigrant screening have recently been revised but accurate calculation of cost-effectiveness is hampered by a lack of empiric data on the comparative performance of tuberculin skin test (TST) and interferon-γ release-assays (IGRA) in immigrants arriving from countries with varying TB incidence. Methods Prospective evaluation of TST and two commercially available IGRAs (QuantiFERON Gold in-tube (QFN-GIT) and T-SPOT.TB) in recent immigrants aged =16 years to quantify test positivity, concordance and factors associated with a positive result for all three tests. We computed yields at different incidence thresholds and the relative cost-effectiveness, using a decision-analysis-model stratified by HIV/drug-resistance, of screening using different latent TB infection (LTBI) screening modalities at varying incidence thresholds supplemented with/without port-of-arrival chest radiography. Results 231 immigrants included; median age 29 (IQR 24–37). TST accepted by 80.9%, read in 93.6%; 30.3% positive. QFN-GIT and T-SPOT.TB positive in 16.6% and 22.5% respectively. Positive TST, QFN-GIT and T-SPOT.TB independently associated with increasing TB incidence in immigrants9 countries of origin (p=0.008, 0.007 and 0.01 respectively). Implementing current guidance (depending on test) would identify 98%–100% of LTBI but also require 97%–99% of the immigrant cohort to be tested; raising the threshold to 150/100 000 (includes immigrants from Indian Subcontinent) would identify 49%–71% of LTBI but require half the cohort to be screened. The three most cost-effective screening strategies (which were more cost-effective than current guidance) were: no CXR at port-of-entry and screen with single-step QFN-GIT at 250/100 000 (Incremental cost-effective ratio (ICER) £21 565.3/per case averted), no CXR at port-of-entry and screen with single-step QFN-GIT at 150/100 000 (averted additional 7.8 cases of active TB, ICER of £31 867.1/per case averted) and no CXR at port-of-entry and screen with single-step QFN-GIT at 40/100 000 which averted a further 9.4 cases (ICER £34 753.5/per case averted). Conclusions Immigrant screening in the UK could cost-effectively and safely eliminate mandatory CXR on arrival by emphasising systematic screening for LTBI with single-step IGRA. An intermediate incidence threshold for screening balances the need to identify as much imported LTBI as possible against limited service capacity.

Introduction In 2006, 72% of active TB cases in the UK occurred in people born overseas (HPA 2008). 48% of new entrants with TB were diagnosed within 5 years of entering the UK and 19% within 2 years (HPA 2008). It is a priority therefore, to identify and appropriately treat those infected with latent TB infection through TB screening programmes (DH 2004). NICE (2006) TB new entrant screening guidelines allow certain groups of new entrants to be screened solely via chest x-ray (CXR), omitting a Tuberculin Skin Test (TST). This potentially under-diagnoses latent TB Infection (LTBI). The aim of this study was to determine whether NICE (2006) criteria are adequate in detecting latent TB. Method A retrospective case-note analysis of new entrants over a 44-month period (2006–2009). All patients were screened using a locally developed ‘Dorset’ algorithm that combined CXR and TST unless contraindicated (see Abstract P54 Figure 1). Each case was then re-evaluated using the NICE algorithm. This allowed direct comparison of each algorithm to detect LTBI. Results 547 new entrants were referred locally for TB screening (2006–2009). 397 attended. 41 (10.3%) patients (all HIV−ve) were diagnosed with LTBI, based on the following outcomes: Abnormal CXR and strongly positive TST=14 (34%). Normal CXR but strongly positive TST=18 (44%). Abnormal CXR but normal TST=9 (22%). Comparison of the two algorithms showed that while all 41 cases were detected using the Dorset algorithm, only 27 cases (65.8 %) were detected using the NICE algorithm. This represents a 34.1% shortfall in LTBI detection using NICE (95% CI 19.63% to 48.67%, 99% CI 15.04% to 53.26%). Discussion This study demonstrated that through the omission of TST, the NICE algorithm missed 14 (34.1%) cases of LTBI compared with the Dorset algorithm. While alternative screening methods such as IGRA are increasing in recognition, these continue to be an expensive option if not provided locally. Therefore TB services without routine access to IGRA can significantly improve their detection of latent TB by simply combining their existing screening tools.

Introduction Using French cut-offs for the Tuberculin Skin Test (TST), results of the TST were compared with the results of an Interferon-γ Release Assay (IGRA) in Healthcare Workers (HCW) after contact to AFB-positive TB patients. Methods Between May 2006 and May 2007, a total of 148 HCWs of the University Hospital in Nantes, France were tested simultaneously with IGRA und TST. A TST was considered to indicate recent latent TB infection (LTBI) if an increase of >10 mm or if TST ≥ 15 mm for those with no previous TST result was observed. For those with a positive TST, chest X-ray was performed and preventive chemotherapy was offered. Results All HCWs were BCG-vaccinated. The IGRA was positive in 18.9% and TST ≥ 10 mm was observed in 65.5%. A recent LTBI was believed to be highly probable in 30.4% following TST. Agreement between IGRA and TST was low (kappa 0.041). In 10 (16.7%) out of 60 HCWs who needed chest X-ray following TST the IGRA was positive. In 9 (20%) out of 45 HCWs to whom preventive chemotherapy was offered following TST the IGRA was positive. Of those considered TST-negative following the French guidelines, 20.5% were IGRA-positive. In a two-step strategy - positive TST verified by IGRA - 18 out of 28 (64.3%) IGRA-positive HCWs would not have been detected using French guidelines for TST interpretation. Conclusion The introduction of IGRA in contact tracings of BCG-vaccinated HCWs reduces X-rays and preventive chemotherapies. Increasing the cut-off for a positive TST does not seem to be helpful to overcome the effect of BCG vaccination on TST.

To the Editor. —The Office of Migrant Health, Department of Health and Human Services, estimates there to be more than 4 million migrant and seasonal farmworkers in the United States. Among other health problems, these workers suffer a significantly higher rate of tuberculosis (TB) infection compared with the general population. This also includes a high rate of asymptomatic TB, found to be 33% in Hispanic migrant workers in one typical study. 1 With a lifetime risk of 10% for developing active TB, it is understandable that this high-risk population constitutes one of the top priorities of the Advisory Council for Elimination of Tuberculosis, Department of Health and Human Services. In attempting to comply with Centers for Disease Control and Prevention recommendations for TB screening, 2 our mobile migrant worker clinic in north central Ohio offered Mantoux tuberculin skin testing to farmworkers and their families from June through September 1993. Approximately

Background : An estimated 2.47 million (2.0-3.1 million) people were living with HIV/AIDS in India by the end of 2006. Among those HIV infected individuals, TB was the commonest opportunistic infection and leading cause of mortality. HIV infection makes a person susceptible to both pulmonary and extra pulmonary forms of TB. Various studies have documented the occurrence of TB from 46 to 65 percent. However, provision of HIV screening services for Tuberculosis out patient attendees is limited at present. Aims : To study feasibility of counseling for HIV screening and document the prevalence of HIV among TB out patient attendees. Methods : This prospective explorative study included persons who sought TB screening at TB unit, Madurai from Jan 2003- Feb 2004. An interview schedule was developed to obtain information on socio-demographic profi le, risk behavior profi le and test results. Information collected includes socio-demographic profile, risk behavior profi le and reaction to test results. Univariata and bivariate analyses were performed using Epi-info 6.04 (CDC, Atlanta, GA, July 1996). Chi-square test, student "t" test and one way ANOVA tests were performed to establish statistical signifi cance between dependent and independent variables Results : This study has found 57.66% chest symptomatic attending TB out patient ward were HIV positive. An analysis of risk profile versus positive results showed that 47(n=75) and 48(n=90) who admitted and denied high-risk behavior respectively, found to be positive to HIV screening test. Conclusion : The researchers suggest that HIV counseling and testing services can be offered to all chest symptomatic attending TB out patient ward. This structural change will make HIV screening more effective and benefi cial to patient community by ensuring early detection HIV infection. DOI: 10.3126/saarctb.v6i1.3060 SAARC J. Tuber. Lung Dis. HIV/AIDS 2009 VI (1) 16-24

Background The compliance of screening for latent tuberculosis (TB) with the tuberculin purified protein derivative (PPD) test is very low among healthcare workers (HCWs) in Israel. Methods This randomized controlled study uses the Health Belief Model (HBM) as a conceptual framework to examine whether providing more information about latent TB and the PPD test increases the response rate for PPD screening among HCWs. All candidate HCWs for latent TB screening were randomly allocated to one of the following two invitations to perform the PPD test: regular letter (control group, n = 97), and a letter with information about latent TB and the PPD test (intervention group, n = 196). Results 293 HCWs were included (185 nurses, and 108 physicians). Overall, 36 (12.3%) HCWs were compliant with the PPD test screening. Compliance with PPD testing in the intervention group was not statistically different from the control group, RR 0.87 (95% CI, 0.46–1.65). Conclusions Compliance for latent TB screening is low among HCWs in northeastern Israel. Providing detailed information about latent TB was not associated with increased test compliance. Understanding existing disparities in screening rates and potential barriers to latent TB screening among HCWs is important in order to move forward and successfully increase screening rates.

Tuberculosis (TB) skin-testing practices in long-term care facilities (LTCFs) in North Carolina (NC) were assessed from a 56% (148/263) response to a comprehensive TB screening questionnaire. TB skin tests were administered to employees on initial employment by 98% and annually by 97% of the LTCFs, generally (74%) by the Mantoux method. Employee skin tests were read at the appropriate time interval of 48 to 72 hours by 91%, but less than half used diameter of induration when interpreting reactive tests. The booster test was performed on new employees at eight (6%) of the LTCFs. TB skin tests were routinely performed on newly admitted residents by 56% or conditionally required by 18%, generally (73%) by the Mantoux method. Resident skin tests were read at the appropriate time interval of 48 to 72 hours by 92%, but again only half correctly interpreted reactive tests as significant. Residents received routine annual skin tests at 71% of the LTCFs, generally (80%) by the Mantoux method. Eight (6%) facilities routinely performed the booster test on newly admitted residents. TB infection prevalence in new employees during 1983 was 8.1% (47/578) in seven LTCFs and in newly admitted residents was 6.4% (7/110) in three LTCFs supplying this data. The five-year mean TB skin test conversion rate among employees was 1.1% (101/9545) in 12 LTCFs and among residents was 0.9% (46/5216) in nine LTCFs supplying this data. Lack of compliance to established TB skin-testing guidelines in NC LTCF was prevalent. In recognition of described endemic and epidemic spread of TB in LTCFs, residents and employees of LTCFs should be screened for TB utilizing established skin-testing practices.

While it is known that a substantial proportion of individuals with tuberculosis disease (TB) present subclinically, usually defined as bacteriologically-confirmed but negative on symptom screening, considerable knowledge gaps remain. Our aim was to review data from TB prevalence population surveys and generate a consistent definition and framework for subclinical TB, enabling us to estimate the proportion of TB that is subclinical, explore associations with overall burden and program indicators, and evaluate the performance of screening strategies. We extracted data from all publicly available prevalence surveys conducted since 1990. Between 36.1% and 79.7% (median, 50.4%) of prevalent bacteriologically confirmed TB was subclinical. No association was found between prevalence of subclinical and all bacteriologically confirmed TB, patient diagnostic rate, or country-level HIV prevalence (P values, .32, .4, and .34, respectively). Chest Xray detected 89% (range, 73%–98%) of bacteriologically confirmed TB, highlighting the potential of optimizing current TB case-finding policies., Our analysis of tuberculosis prevalence surveys showed that a median of 50.4% of prevalent bacteriologically confirmed tuberculosis was subclinical, meaning negative on symptom screening. Chest X ray detected 89% of cases. This could potentially suggest a change in tuberculosis case-finding policies.

Background To inform the choice of an appropriate screening and diagnostic algorithm for tuberculosis (TB) screening initiatives in different epidemiological settings, we compare algorithms composed of currently available methods. Methods Of twelve algorithms composed of screening for symptoms (prolonged cough or any TB symptom) and/or chest radiography abnormalities, and either sputum-smear microscopy (SSM) or Xpert MTB/RIF (XP) as confirmatory test we model algorithm outcomes and summarize the yield, number needed to screen (NNS) and positive predictive value (PPV) for different levels of TB prevalence. Results Screening for prolonged cough has low yield, 22% if confirmatory testing is by SSM and 32% if XP, and a high NNS, exceeding 1000 if TB prevalence is ≤0.5%. Due to low specificity the PPV of screening for any TB symptom followed by SSM is less than 50%, even if TB prevalence is 2%. CXR screening for TB abnormalities followed by XP has the highest case detection (87%) and lowest NNS, but is resource intensive. CXR as a second screen for symptom screen positives improves efficiency. Conclusions The ideal algorithm does not exist. The choice will be setting specific, for which this study provides guidance. Generally an algorithm composed of CXR screening followed by confirmatory testing with XP can achieve the lowest NNS and highest PPV, and is the least amenable to setting-specific variation. However resource requirements for tests and equipment may be prohibitive in some settings and a reason to opt for symptom screening and SSM. To better inform disease control programs we need empirical data to confirm the modeled yield, cost-effectiveness studies, transmission models and a better screening test. Electronic supplementary material The online version of this article (doi:10.1186/1471-2334-14-532) contains supplementary material, which is available to authorized users.