Prevalence of Latent Tuberculosis Infection Among Healthy Young Children and Adolescents and a Two-step Approach for the Diagnosis of Tuberculosis Infection in Chengdu, China

BACKGROUND

China has a high burden of tuberculosis and latent tuberculosis infection (LTBI). The aim of this study was to estimate the prevalence of LTBI among healthy young children and adolescents and test a 2-step approach to explore the threshold for the diagnosis of tuberculosis infection in Chengdu, China.

METHODS

Healthy preschool children and school-going children in Chengdu, Sichuan Province, were screened for LTBI using the tuberculin skin test (TST). Preschool children with TST ≥ 5 mm also underwent interferon-γ release assay (IGRA) to explore the threshold of this 2-step approach.

RESULTS

In total, 5667 healthy young children and adolescents completed TST test between July 2020 and January 2021 and were included in the present analysis. The age of the participants ranged from 2.4 to 18 years (median 7.25 ± 4.514 years), of which 2093 (36.9%) were younger than 5 years. The overall prevalence of LTBI was 6.37% and 6.64% in children younger than 5 years old. Fourteen of the 341 preschool children with TST ≥5 mm were interferon-γ release assay positive, of which 4 showed a TST result of 5-10 mm, and 6 preschool children received preventive treatment for LTBI.

CONCLUSIONS

Healthy young children and adolescents should also be considered as important target populations for LTBI screening. TST can be recommended for first-line screening as part of a 2-step approach for LTBI screening using a positive threshold of 5 mm.

Brief Report: Yield of Repeat Tuberculin Skin Testing for People Living With HIV in Brazil

OBJECTIVES

In Brazil, annual tuberculin skin tests (TSTs) are recommended for people living with HIV (PLWH) with CD4 >350, with tuberculosis preventive therapy provided on test conversion. We aimed to determine the yield of repeat TSTs for PLWH.

DESIGN

Secondary analysis of the stepped-wedge, cluster-randomized THRio trial for isoniazid preventive therapy (IPT) to prevent tuberculosis (TB).

METHODS

We analyzed data from newly registered PLWH with negative baseline TST results. We calculated the number of TST conversions after 1 and/or 2 years among patients eligible for follow-up TSTs, the proportion of converters initiating IPT, and incidence of TB/death.

RESULTS

Among 1770 PLWH with a negative baseline TST, 679 (38%) were female and median age was 36 years (IQR 29-43). Eighty-six (5%) developed TB or died within 1 year. Among 1684 eligible for a follow-up 1-year TST, 582 (35%) were tested and 53 (9%) were positive. Forty-nine converters (92%) started IPT. Of 529 patients with a negative 1-year TST, 7 (1%) developed TB or died over the following year. Of 522 patients eligible for a 2-year TST, 158 (30%) were tested and 13 (8%) were positive. Ten converters (77%) started IPT. Of 1102 patients who did not receive a 1-year TST, 33 (3%) developed TB or died. Of the 1069 patients eligible for a 2-year TST, 259 (24%) were tested and 34 (13%) were positive. Thirty converters (88%) started IPT.

CONCLUSIONS

In this cohort of PLWH in Brazil, TST conversion was high among those retested, but only 48% received a follow-up TST within 2 years.

IgG4-Related Disease With Tuberculosis: A Case Report and Retrospective Review of Patients in a Single Center

Background

IgG4-related disease (IgG4-RD) is a recently recognized systemic fibro-inflammatory disease of unknown cause involving many organs including pancreas, salivary glands, and lymph nodes. Chronic tuberculosis (TB) infection has been reported in IgG4-RD, but the prevalence of TB infection has not been evaluated in IgG4-RD.

Methods

Characterization of a patient with IgG4-RD by physical examination, laboratory tests, magnetic resonance imaging (MRI) and histological examination. TB infection was evaluated by medical history, radiological examinations, sputum examinations, tubercular skin test (TST) and interferon gamma (IFN-γ) release assay test (IGRA). Medical records of IgG4-RD patients were reviewed in our institute from February 2015 to September 2020 to explore the prevalence of TB infection in IgG4-RD.

Results

We described a 40-year-old Chinese man presented with headache and diplopia. Physical examination revealed bitemporal hemianopsia and limited abduction of both eyes. MRI revealed uniformly enhancing mass overlying clivus with dural tail sign. Laboratory data revealed elevation of IgG4 (1.9g/L), and TB-IGRA demonstrated significantly elevated IFN-γ (414.21 pg/ml). The clivus lesion was subtotally removed and IgG4 was strongly positive on immunohistochemical staining. The diagnosis of IgG4-RD was established, and the patient received treatment of corticosteroids, methotrexate, and cyclophosphamide with isoniazid prophylaxis. Consequently, the mass shrank remarkably within 3 months. A similar concurrence of TB disease or latent TB infection (LTBI) and IgG4-RD was present in 17/47 (36.2%) patients in our institute.

Conclusion

High frequency of TB/LTBI presented in patients with IgG4-RD. Patients with IgG4-RD and LTBI should be closely monitored for resurgence of TB. Whether TB represents a risk for IgG4-RD should be further investigated in prospective cohort.

Implementation of latent tuberculosis infection screening and treatment among newly arriving immigrants in the Netherlands: A mixed methods pilot evaluation

INTRODUCTION

To reach pre-elimination levels of tuberculosis (TB) incidence in the Netherlands, prevention of TB among immigrants through diagnosis and treatment of latent TB infection (LTBI) is needed. We studied the feasibility of a LTBI screening and treatment program among newly arriving immigrants for national implementation.

METHODS

We used mixed methods to evaluate the implementation of LTBI screening and treatment in five Public Health Services (PHS) among immigrants from countries with a TB incidence >50/100,000 population. We used Poisson regression models with robust variance estimators to assess factors associated with LTBI diagnosis and LTBI treatment initiation and reported reasons for not initiating or completing LTBI treatment. We interviewed five PHS teams using a semi-structured method to identify enhancing and impeding factors for LTBI screening and treatment.

RESULTS

We screened 566 immigrants; 94 (17%) were diagnosed with LTBI, of whom 49 (52%) initiated and 34 (69%) completed LTBI treatment. LTBI diagnosis was associated with male gender, higher age group, higher TB incidence in the country of origin and lower level of education. Treatment initiation was associated with PHS (ranging from 29% to 86%), lower age group, longer intended duration of stay in the Netherlands, and lower level of education. According to TB physicians, clients and their consulted physicians in the home country lacked awareness about benefits of LTBI treatment. Furthermore, TB physicians questioned the individual and public health benefit of clients who return to their country of origin within the foreseeable future.

CONCLUSIONS

Doubt of physicians in both host country and country of origin about individual and public health benefits of LTBI screening and treatment of immigrants hampered treatment initiation: the high initiation proportion in one PHS shows that if TB physicians are committed, the LTBI treatment uptake can be higher.

Role Of Tuberculin Test As A Diagnostic Tool For Tuberculosis

BACKGROUND

Childhood Tuberculosis remains one of the major public health concerns in developing countries like Pakistan and is responsible for high rates of morbidity and mortality in children. Although tuberculin skin test is very commonly used by physicians all over the world, its interpretation always remains difficult and challenging. The objective of this study was to determine the frequency of positive tuberculin skin test in vaccinated and unvaccinated children suffering from tuberculosis.

METHODS

This Cross-sectional study was conducted in the department of Paediatric Ayub Teaching Hospital, Abbottabad from 1st February 2015 to 30th April 2016. A total of 150 patients were observed in this study. Children of either gender who were aged 1-15 years admitted in ward with tuberculosis were included in the study by using nonprobability convenient sampling technique. We injected 0.1 ml (10 units) of tuberculin purified protein derivative (PPD) into the anterior surface of the forearm and induration was read at 72 hours after administration. Data was entered and analysed using SPSS version 10.

RESULTS

Out of 150 children, 84 (56%) were males and 66 (44%) were females. The mean age was 7.8±3.84 years. Of these 75 (50%) were vaccinated and 75 (50%) were unvaccinated. In vaccinated Group 5.3% children had positive tuberculin skin test while in unvaccinated Group 2.7% children had positive tuberculin skin test and this difference was found statistically insignificant (pvalue= 0.40). Pulmonary TB was the diagnosis in 67 (44.7%), TBM in 65 (43.3%), abdominal TB in 7 (4.7%), disseminated TB in 4 (2.7%) and military TB in 7 (4.7%) patients.

CONCLUSIONS

The positivity of tuberculin skin test in vaccinated and unvaccinated children suffering from tuberculosis was found to be insignificant in our study. We conclude that Tuberculin Skin Test should not be used as a sole diagnostic tool for diagnosing the disease in children of our region..

Care Cascade for targeted tuberculosis testing and linkage to Care in Homeless Populations in the United States: a meta-analysis

BACKGROUND

Homelessness increases the risk of tuberculosis (TB) disease and latent TB infection (LTBI), but persons experiencing homelessness often lack access to testing and treatment. We assessed the yield of TB testing and linkage to care for programs targeting homeless populations in the United States.

METHODS

We conducted a comprehensive search of peer-reviewed and grey literature, adapting Cochrane systematic review methods. Two reviewers independently assessed study eligibility and abstracted key data on the testing to care cascade: number of persons reached, recruited for testing, tested for LTBI, with valid test results, referred to follow-up care, and initiating care. We used random effects to calculate pooled proportions and 95% confidence intervals (CI) of persons retained in each step via inverse-variance weighted meta-analysis, and cumulative proportions as products of adjacent step proportions.

RESULTS

We identified 23 studies published between 1986 and 2014, conducted in 12 states and 15 cities. Among studies using tuberculin skin tests (TST) we found that 93.7% (CI 72.4-100%) of persons reached were recruited, 97.9% (89.3-100%) of those recruited had tests placed, 85.5% (78.6-91.3%) of those with tests placed returned for reading, 99.9% (99.6-100%) of those with tests read had valid results, and 24.7% (21.0-28.5%) with valid results tested positive. All persons testing positive were referred to follow-up care, and 99.8% attended at least one session of follow-up care. Heterogeneity was high for most pooled proportions. For a hypothetical cohort of 1000 persons experiencing homelessness reached by a targeted testing program using TST, an estimated 917 were tested, 194 were positive, and all of these initiated follow-up care.

CONCLUSIONS

Targeted TB testing of persons experiencing homelessness appears effective in detecting LTBI and connecting persons to care and potential treatment. Future evaluations should assess diagnostic use of interferon gamma release assays and completion of treatment, and costs of testing and treatment.

Tuberculosis screening among HIV-infected patients: tuberculin skin test vs. interferon-gamma release assay

National guidelines recommend screening for latent tuberculosis infection (LTBI) in all HIV-infected patients. Thus, the objective of this study was to measure protocol adherence to national guidelines regarding LTBI screening for HIV-infected patients entering care at an urban primary care clinic specializing in HIV care, identify clinical and other characteristics associated with adherence, and determine whether transitioning from the tuberculin skin test (TST) to the interferon-gamma release assay (IGRA) improved adherence. We conducted a retrospective study using protocol adherence to LTBI screening guidelines within twelve months of entering care at an HIV clinic as the primary outcome. Successful protocol adherence was defined as the placement and reading of a TST, performance of an IGRA, or a note in study clinic records documenting prior testing or treatment for tuberculosis in an outside setting. Multivariable modified Poisson regression models were used in analyses. Overall, 32% (n = 118/372) of patients received LTBI screening within twelve months of entering care. Protocol adherence to LTBI screening guidelines increased from 28% to 37% following the transition from TST to IGRA screening. IGRA screening [adjusted prevalence ratio: 1.45, 95% confidence limits: (1.07, 1.96)], male sex [1.47 (1.05, 2.07)], transfer patient status [1.51 (1.05, 2.18)], and greater than one year of clinic attendance [1.62 (1.06, 2.48)] were independently associated with protocol adherence. Among patients without prior LTBI screening or treatment, patients entering the clinic in 2013 under the IGRA screening protocol were more likely to be screened for LTBI compared to patients entering under the TST screening protocol (34.3% vs. 9.7%, p < 0.001). In conclusion, transitioning from TST to IGRA-based screening improved adherence to screening guidelines. However, further work on improving adherence to LTBI screening guidelines among HIV-infected patients is needed.

Use of tuberculin skin test for assessment of immune recovery among previously malnourished children in Ethiopia

OBJECTIVE

To compare levels of immunity in children recovering from severe acute malnutrition (cases) against those of community controls (controls).

RESULTS

At baseline children recovering from severe acute malnutrition had lower, mid upper arm circumference (122 mm for cases and 135 mm for controls; p < 0.001), weight-for-height Z-score (- 1.0 for cases and - 0.5 for controls; p < 0.001), weight-for-age Z-score (- 2.8 for cases and - 1.1 for controls; p < 0.001) and height/length-for-age Z-score (- 3.6 for cases and - 1.4 for controls; p < 0.001), than controls. Age and gender matched community controls. At baseline, prevalence of a positive tuberculin skin test, assessed by cutaneous delayed-type hypersensitivity reaction skin test, was very low in both cases (3/93 = 3.2%) and controls (2/94 = 2.1%) and did not significantly increase at 6 months follow up (6/86 = 7.0% in cases and 3/84 = 3.4% in controls). The incidences of common childhood morbidities, namely fever, diarrhoea and cough, were 1.7-1.8 times higher among cases than controls. In conclusion, these results show that tuberculin skin test does not enable any conclusive statements regarding the immune status of patients following treatment for severe acute malnutrition. The increased incidence of infection in cases compared to controls suggests persistence of lower resistance to infection even after anthropometric recovery is achieved.

National position statement for the management of latent tuberculosis infection

The primary role of any tuberculosis (TB) control program is to ensure the prompt identification and effective treatment of active disease. The host immune system often succeeds in containing the initial (or primary) infection with Mycobacterium tuberculosis (Mtb), but may fail to eliminate the pathogen. The persistence of viable organisms explains the potential for the development of active disease years or even decades after infection. This is known as latent tuberculosis infection (LTBI) although, rather than a distinct entity, this probably represents part of a dynamic spectrum. Individuals with LTBI are asymptomatic and it is therefore clinically undetectable. The World Health Organization (WHO) estimates that one-third of the global population has been infected with Mtb, with highest prevalence of LTBI in countries/regions with the highest prevalence of active disease. In 2013, 88% of 1322 notifications in Australia were in the overseas-born population (incidence 19.5 per 100,000 v. 1.0 per 100,000), with this proportion rising over the course of the last decade. Combined with epidemiological evidence of low local transmission, this strongly implies that the vast majority resulted from reactivation of latent infection acquired prior to immigration. Contrasting trends in TB incidence in other developed countries probably reflect differences in policy regarding LTBI.

CONCLUSION

The diagnosis and treatment of LTBI represents an important opportunity for intervention by jurisdictional TB control programs.

Comparing tuberculin skin test and interferon γ release assay (T-SPOT.TB) to diagnose latent tuberculosis infection in household contacts

BACKGROUND/AIMS

The tuberculin skin test (TST) and interferon γ release assay are currently used as diagnostic tools to detect latent tuberculosis (TB) infection; however, there are inconsistencies about the degree of agreement between the tests. We aimed to evaluate the concordance rate between the two tests in household contacts of a country with intermediate TB burden, where most people were vaccinated.

METHODS

We recruited household contacts who spent > 8 hours daily with patients with microbiologically confirmed active pulmonary TB, and received both TST and T-SPOT.TB (Oxford Immunotec) simultaneously. The degree of agreement was analysed according to TST cutoff and Bacille Calmette-Guerin (BCG) vaccination status. Relevant factors were analysed to establish the association with TST or T-SPOT.TB.

RESULTS

Among 298 household contacts, 122 (40.9%) were spouses, and 250 (83.9%) had received BCG vaccination. In the contact sources, 117 (39.3%) showed a positive result for acid-fast bacillus (AFB) sputum smear and 109 (36.6%) had cavities. The highest agreement rate of 69.5% and κ value of 0.378 were found with a 10 mm cutoff. Spouse, time interval from TB diagnosis to test, and AFB sputum smear positivity were significantly associated with a positive result for T-SPOT.TB. Sex, BCG vaccination, and cavity on chest computed tomography were related to TST positivity.

CONCLUSIONS

The present study suggested it was not possible for TST and T-SPOT.TB to replace each other because of considerable discrepancy between the two tests in household contacts in a country with intermediate TB prevalence.

Status of Tuberculosis services in Indian Prisons

INTRODUCTION

Prisons are known to be a high risk environment for tuberculosis (TB) due to overcrowding, low levels of nutrition, poor infection control and lack of accessible healthcare services. India has nearly 1400 prisons housing 0.37 million inmates. However, information on, availability of diagnostic and treatment services for TB in the prison settings is limited. This study examined the availability of TB services in prisons of India. Simultaneously, prison inmates were screened for tuberculosis.

METHOD

The study was conducted in 157 prisons across 300 districts between July-December 2013. Information on services available and practices followed for screening, diagnosis and treatment of TB was collected. Additionally, the inmates and prison staff were sensitised on TB using interpersonal communication materials. The inmates were screened for cough ≥2 weeks as a symptom of TB. Those identified as presumptive TB patients (PTBP) were linked with free diagnostic and treatment services.

RESULTS

Diagnostic and treatment services for TB were available in 18% and 54% of the prisons respectively. Only half of the prisons screened inmates for TB on entry, while nearly 60% practised periodic screening of inmates. District level prisons (OR, 6.0; 95% CI, 1.6-22.1), prisons with more than 500 inmates (OR, 52; 95% CI, 1.4-19.2), and prisons practising periodic screening of inmates (OR, 2.7; 95% CI, 1.0-7.2) were more likely to diagnose TB cases. 19% of the inmates screened had symptoms of TB (cough ≥2 weeks) and 8% of the PTBP were diagnosed with TB on smear microscopy.

CONCLUSION

The TB screening, diagnostic and treatment services are sub-optimal in prisons in India and need to be strengthened urgently.

Quantitative genetic analysis of the bTB diagnostic single intradermal comparative cervical test (SICCT)

BACKGROUND

Bovine tuberculosis (bTB) is a disease of significant economic importance and is a persistent animal health problem with implications for public health worldwide. Control of bTB in the UK has relied on diagnosis through the single intradermal comparative cervical test (SICCT). However, limitations in the sensitivity of this test hinder successful eradication and the control of bTB remains a major challenge. Genetic selection for cattle that are more resistant to bTB infection can assist in bTB control. The aim of this study was to conduct a quantitative genetic analysis of SICCT measurements collected during bTB herd testing. Genetic selection for bTB resistance will be partially informed by SICCT-based diagnosis; therefore it is important to know whether, in addition to increasing bTB resistance, this might also alter genetically the epidemiological characteristics of SICCT.

RESULTS

Our main findings are that: (1) the SICCT test is robust at the genetic level, since its hierarchy and comparative nature provide substantial protection against random genetic changes that arise from genetic drift and from correlated responses among its components due to either natural or artificial selection; (2) the comparative nature of SICCT provides effective control for initial skin thickness and age-dependent differences; and (3) continuous variation in SICCT is only lowly heritable and has a weak correlation with SICCT positivity among healthy animals which was not significantly different from zero (P > 0.05). These emerging results demonstrate that genetic selection for bTB resistance is unlikely to change the probability of correctly identifying non-infected animals, i.e. the test's specificity, while reducing the overall number of cases.

CONCLUSIONS

This study cannot exclude all theoretical risks from selection on resistance to bTB infection but the role of SICCT in disease control is unlikely to be rapidly undermined, with any adverse correlated responses expected to be weak and slow, which allow them to be monitored and managed.

Tuberculosis in Poland in 2014

AIM OF THE STUDY

To evaluate the main features of TB epidemiology in 2014 in Poland and to compare with the data on the same phenomena in EU/EEA countries.

METHODS

Analysis of case- based data on TB patients from National TB Register, data on anti-TB drugsusceptibility testing results in cases notified in 2014, data from National Institute of Public Health- NationalInstitute of Hygiene on cases of tuberculosis as AIDS-defining disease, data from Central Statistical Office ondeaths from tuberculosis based on death certificates, data from ECDC report „ European Centre for DiseasePrevention and Control/WHO Regional Office for Europe. Tuberculosis surveillance and monitoring in Europe 2016. Stockholm: European Centre for Disease Prevention and Control, 2016”.

RESULTS

6 698 TB cases were reported in Poland in 2014. The incidence rate was 17.4 cases per 100 000, withlarge variability between voivodeships from 9.3 to 26.5 per 100 000. The mean annual decrease of TB incidence in 2010- 2014 was 2.1%. 6 066 cases had no history of previous treatment i.e. 15.8 per 100 000. 632 cases i.e. 1.6 per 100 000 – 9.4% of all registered subjects were relapses. The number of all notified pulmonary tuberculosis cases in 2014 was 6311 i.e. 16.4 per 100 000. Pulmonary cases represented 94.2% of all TB cases. In the presented year 387 extrapulmonary TB cases were reported. Children with TB (70 cases) accounted for 1.0% of all cases notified in Poland. The incidence of tuberculosis increases with age from 1.2 per 100 000 among children to 30.4 per 100 000 among patients 65 years old and older. The incidence among men i.e. 24.6 per 100 000 was 2.3 times higher than among women i.e. 10.7 per 100 000. The biggest difference in the TB incidence between the two sex groups occurred in persons aged 45 to 49 years – 40.4 vs. 9.3. The TB incidence in rural population was lower than in urban, respectively 17.0 per 100 000 and 17.7 per 100 000. The number of all registered culture positive TB cases, including relapses, was 4 781. Culture-confirmed cases constituted 71.4% of all TB cases and 72.9% of all pulmonary TB cases. The number of smear-positive pulmonary TB cases reported in 2014 was 2800 i.e. 7.3 per 100 000 respectively what constituted 44.4% of all pulmonary TB cases. TB was initial AIDS indicative disease in 13 persons. In Poland in 2014 there were 35 cases with MDR-TB (including 7 patients of foreign origin) and 97 patients with resistance to isoniazid only, constituting respectively 0.8% and 2.2% of cases with known DST results (DSTs were done in 93.3% of all culture-confirmed TB cases). In 2014, there were 49 foreign-origin TB cases reported in Poland. There were 532 deaths due to tuberculosis reported in 2013 – 1.4 per 100 000; 518 and 14 from extrapulmonary tuberculosis. Mortality among males – 2.2 per 100.000 – was 3.6 X higher than among females – 0.6. 38,5% of all TB deaths were cases 65 years old and older – 3.7 per 100 000. There were no deaths from tuberculosis in children. TB was cause of death in one adolescent. TB mortality in 2013 constituted 0.14% of total mortality in Poland and 27.1% of mortality from infectious diseases.

CONCLUSIONS

In Poland in 2014 the incidence of tuberculosis was higher than the average in EU/EEA countries. The highest incidence rates occurred in older age groups. The incidence in men was more than 2 times higher than in women. In Poland, unfavorable phenomena as tuberculosis in children, tuberculosis in persons infected with HIV and MDR-TB are less common than in EU/EEA countries.

Evaluation of a diagnostic flow chart applying medical thoracoscopy, adenosine deaminase and T-SPOT.TB in diagnosis of tuberculous pleural effusion

OBJECTIVE

To evaluate a diagnostic flow chart applying medical thoracoscoy (MT), adenosine deaminase (ADA) and T-SPOT.TB in diagnosis of tuberculous pleural effusion (TPE) at a high TB burden country.

PATIENTS AND METHODS

136 patients with pleural effusion (PE) were enrolled and divided into TPE and Non-TPE group. MT (histology), PE ADA and T-SPOT.TB were conducted on all patients. ROC analysis was performed for the best cut-off value of PE ADA in detection of TPE. The diagnostic flow chart applying MT, ADA and T-SPOT.TB was evaluated for improving the limitations of each diagnostic method.

RESULTS

ROC analysis showed that the best cut-off value of PE ADA was 30U/L. The sensitivity and specificity of these tests were calculated respectively to be: 71.4% (58.5%-81.6%) and 100% (95.4-100.0%) for MT, 92.9% (83.0-97.2%) and 68.8% (57.9-77.9%) for T-SPOT.TB, and 80.0% (69.6-88.1%) and 92.9% (82.7-98.0%) for PE ADA. The sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, positive predictive value and negative predictive value of the diagnostic flow chart were 96.4% (87.9-99.0%), 96.3% (89.6-98.7%), 25.714, 0.037, 97.4 and 94.9, respectively.

CONCLUSIONS

The diagnostic flow chart applying MT, ADA and T-SPOT.TB is an accurate and rapid diagnostic method in detection of TPE.

Costs of Implementing and Maintaining a Tuberculin Skin Test Program in Hospitals and Health Departments

Objective:

To determine (1) the annual costs of implementing and maintaining tuberculin skin test (TST) programs at participating study sites, (2) the cost of the TST program per healthcare worker (HCW), and (3) the outcomes of the TST programs, including the proportion of HCWs with a documented TST conversion and the proportion who accepted and completed treatment for latent TB infection, before and after the implementation of staffTRAK-TB software (Centers for Disease Control and Prevention, Atlanta, GA).

Design:

Cost analysis in which costs for salaries, training, supplies, radiography, and data analysis were collected for two 12-month periods (before and after the implementation of staffTRAK-TB).

Setting:

Four hospitals (two university and two city) and two health departments (one small county and one big city).

Results:

The annual cost of implementing and maintaining a TST program ranged from $66,564 to $332,728 for hospitals and $92,886 to $291,248 for health departments. The cost of the TST program per HCW ranged from $41 to $362 for hospitals and $176 to $264 for health departments.

Conclusions:

Costs associated with implementing and maintaining a TST program varied widely among the participating study sites, both before and after the implementation of staffTRAK-TB. Compliance with the TB infection control guidelines of the Centers for Disease Control and Prevention may require a substantial investment in personnel time, effort, and commitment.

Utility of Dual Skin Tests to Evaluate Tuberculin Skin Test Reactions of 10 to 14 mm in Healthcare Workers

Objective:

To define the utility of 10- to 14-mm reactions to a Mycobacterium tuberculosis purified protein derivative (PPD) skin test for healthcare workers (HCWs).

Design:

Blinded dual skin testing, using PPD and M. avium sensitin, of HCWs at a single medical center who had a 10-to 14-mm reaction to PPD when tested by personnel from the Occupational Health Department as part of routine annual screening.

Setting:

A single tertiary-care academic medical center.

Participants:

Employees of the medical center who underwent routine annual PPD screening and were identified by the Occupational Health Department as having a reaction of 10 to 14 mm to PPD.

Results:

Nineteen employees were identified as candidates and 11 underwent dual skin testing. Only 4 (36%) had repeat results for PPD in the 10- to 14-mm range, whether read by Occupational Health Department personnel or study investigators. For only 5 (45%) of the subjects did the Occupational Health Department personnel and study investigators concur (± 3 mm) on the size of the PPD reaction. Two of the 4 subjects with reactions of 10 to 14 mm as measured by the study investigators were M. avium sensitin dominant, 1 was PPD dominant, and 1 was nondominant.

Conclusion:

A reaction of 10 to 14 mm to PPD should not be used as an indication for the treatment of latent tuberculosis (TB) infection in healthy HCWs born in the United States with no known exposure to TB.

Tuberculosis in Poland in 2013

AIM OF THE STUDY

To evaluate the main features of TB epidemiology in 2013 in Poland and to compare with the corresponding EU/EEA data.

METHODS

Analysis of case- based clinical and demographic data on TB patients from Central TB Register, of data submitted by laboratories on anti-TB drug susceptibility testing results in cases notified in 2013, data from National Institute of Public Health- National Institute of Hygiene on cases of tuberculosis as AIDS-defining disease, from Central Statistical Office on deaths from tuberculosis based on death certificates, data from ECDC report "European Centre for Disease Prevention and Control/WHO Regional Office for Europe. Tuberculosis surveillance and monitoring in Europe 2015. Stockholm: European Centre for Disease Prevention and Control, 2015".

RESULTS

7250 TB cases were reported in Poland in 2013. The incidence rate was 18.8 cases per 100 000, with large variability between voivodships from 9.9 to 27.4. The mean annual decrease of TB incidence in 2009-2013 was 2.0%. 6403 cases had no history of previous treatment (rate 16.6). The number of all notified pulmonary tuberculosis cases was 6835; 17.8 per 100 000. The proportion of extrapulmonary tuberculosis among all registered cases was 5.7% (415 cases). In 2013, 34 patients had fibrous-cavernous pulmonary tuberculosis (0.5% of all cases of pulmonary tuberculosis). TB was diagnosed in 116 children (1.6% of all cases, incidence 2.0). The incidence of tuberculosis increased progressively with age to 33.7 among patients 65 years old and older. The mean age of new TB cases was 53.5 years. The incidence among men (26.8) was more than two times higher than among women (11.4). The incidence rate in rural population was lower than in urban areas; 17.1 vs. 20.0. Bacteriologically confirmed pulmonary cases (4825) constituted 68,2% of all pulmonary TB cases. The number of smear positive pulmonary TB cases was 2859 (61.3% of culture confirmed pulmonary cases). There were 52 foreigners registered among all cases of tuberculosis in Poland (0.7%) and 250 cases registered among prisoners (rate 298.0). There were 40 patients with MDR-TB (0.8% of cases with known DST results). TB was AIDS indicative disease in 35 cases. There were 630 deaths due to tuberculosis in 2012 (1.6 TB deaths per 100 000). Mortality among males--2.6--was more than 3 times higher than among females--0.8.

CONCLUSIONS

In Poland in 2013 the incidence of tuberculosis was higher than the average in EU/EEA countries. The highest incidence rates occurred in older age groups. The incidence in men was more than 2 times higher than in women. The incidence of tuberculosis in children and the percentage of patients with drug- resistant tuberculosis are lower than average in the EU/EEA and that is favorable for epidemiological situation of tuberculosis in our country.

Quality of diagnostic and treatment practices of pulmonary tuberculosis management amongst health practitioners in Haryana, north India

INTRODUCTION

Early diagnosis and supervised treatment remains the mainstay for tuberculosis (TB) control in India.

METHODS

A facility-based cross-sectional study was conducted to assess diagnostic and treatment practices of tuberculosis management as per the Revised National Tuberculosis Control Programme at a secondary level health facility in north India. This hospital mostly caters to rural and peri-urban populations in the Ballabgarh block of Faridabad district, Haryana. A sample size of 244 was calculated. Consecutive chest symptomatic patients were recruited in the study. Information about socio-demographic characteristics and treatment was obtained from a routine history-taking process in the outpatient clinic. Results were expressed as mean, standard deviation (SD) and odds ratio (OR) with 95% confidence interval (CI).

RESULTS

A total of 250 pulmonary TB suspects were recruited, out of which 55.4% were males and mean age of study participants was 35.4 years (SD 14.6). Almost half (47.1%) of the participants had sought treatment from government hospitals, followed by 46.7% from private hospitals. Those who had visited a private facility were significantly more likely not to receive sputum acid-fast bacillus (AFB) diagnostic testing (OR=7.26, 95% CI 4.04-13.08), likely to be taking a second-line anti-TB drug as an antibiotic trial (OR=3.65, 95% CI 1.17-11.30), be empirically taking anti-TB drugs (OR=5.28, 95% CI 1.50-118.64) and getting a serological test done (OR=9.58, 95% CI 1.20-76.0) than those who went to a government health facility. Those who made at least three visits to a private facility were significantly more likely to have taken a second-line anti-TB drug as an antibiotic trial (OR=3.56, 95% CI 1.36- 9.28) and be empirically taking anti-TB drugs (OR=5.75, 95% CI 2.18-15.20) than those that made fewer than three visits.

CONCLUSIONS

This study documented inappropriate diagnostic and treatment practices in TB management and highlights the need to generate awareness about it among health practitioners in north India.

T-CELL RESPONSES ASSESSED USING IGRA AND TST ARE NOT CORRELATED WITH AFB GRADE AND CHEST RADIOGRAPH IN PULMONARY TUBERCULOSIS PATIENTS

A definitive marker determining the bacillary load of Mycobacterium tuberculosis (MTB), the causative agent of tuberculosis (TB), and hence disease severity, is required for patient monitoring and management. In this study, the association among T-cell responses based on the interferon-gamma release assay (IGRA) and the tuberculin skin test (TST), the sputum acid-fast bacilli (AFB) grade and types of radiological lesions were analyzed in new cases of pulmonary TB patients (n = 54) at Srinagarind Hospital, Khon Kaen, Thailand between September 1, 2012 and March 31, 2014. It was found that infiltrative and cavitary lesions from chest radiographs were associated with high sputum AFB grade (p = 0.048). T-cell responses from both IGRA and TST were not correlated with sputum AFB grade. Neither IGRA nor TST was correlated with the bacillary load as defined by AFB grade and chest radiographs. Patients with cavitary lesions on chest radiographs tended to have high IFN-γ concentrations and large TST indurations. In addition, TB patients with previous BCG vaccination showed significantly higher IFN-γ induction compared to the non-vaccinated group (p = 0.001). This study showed T-cell responses based on both IGRA and TST were not correlated with AFB grade and chest radiograph. In areas of high rates of BCG vaccination, as in Thailand, the BCG may affect IGRA and TST interpretations.

Comparison of interferon-γ release assay to two cut-off points of tuberculin skin test to detect latent Mycobacterium tuberculosis infection in primary health care workers

BACKGROUND

An interferon-γ release assay, QuantiFERON-TB (QFT) test, has been introduced an alternative test for the diagnosis of latent Mycobacterium tuberculosis infection (LTBI). Here, we compared the performance of QFT with tuberculin skin test (TST) measured at two different cut-off points among primary health care work (HCW) in Brazil.

METHODS

A cross-sectional study was carried out among HCWs in four Brazilian cities with a known history of high incidence of TB. Results of the QFT were compared to TST results based on both ≥5 mm and ≥10 mm as cut-off points.

RESULTS

We enrolled 632 HCWs. When the cut-off value of ≥10 mm was used, agreement between QFT and TST was 69% (k = 0.31), and when the cut-off of ≥5 mm was chosen, the agreement was 57% (k = 0.22). We investigated possible factors of discordance of TST vs QFT. Compared to the TST-/QFT- group, risk factors for discordance in the TST+/QFT- group with TST cut-off of ≥5 mm included age between 41-45 years [OR = 2.70; CI 95%: 1.32-5.51] and 46-64 years [OR = 2.04; CI 95%: 1.05-3.93], BCG scar [OR = 2.72; CI 95%: 1.40-5.25], and having worked only in primary health care [OR = 2.30; CI 95%: 1.09-4.86]. On the other hand, for the cut-off of ≥10 mm, BCG scar [OR = 2.26; CI 95%: 1.03-4.91], being a household contact of a TB patient [OR = 1.72; CI 95%: 1.01-2.92] and having had a previous TST [OR = 1.66; CI 95%: 1.05-2.62], were significantly associated with the TST+/QFT- group. No statistically significant associations were found among the TST-/QFT+ discordant group with either TST cut-off value.

CONCLUSIONS

Although we identified BCG vaccination to contribute to the discordance at both TST cut-off measures, the current Brazilian recommendation for the initiation of LTBI treatment, based on information gathered from medical history, TST, chest radiograph and physical examination, should not be changed.

Poor agreement between QuantiFERON-TB Gold test and tuberculin skin test results for the diagnosis of latent tuberculosis infection in rheumatoid arthritis patients and healthy controls

BACKGROUND/AIMS

We investigated the agreement between the QuantiFERON-TB Gold (QFT-Gold) test and the tuberculin skin test (TST) in the diagnosis of latent tuberculosis infection in patients with rheumatoid arthritis (RA), compared with healthy controls, in Korea.

METHODS

We recruited 64 patients with RA and 79 healthy controls at two university hospitals in South Korea. The participants underwent both the QFT-Gold test and the TST simultaneously between August 2006 and February 2009. All patients were diagnosed using the classification criteria for RA revised in 1987 by the American College of Rheumatology. Bacillus Calmette-Guérin vaccination status and current medications were evaluated, and disease activities were assessed using the Disease Activity Score in 28 joints. Eleven patients with RA produced indeterminate QFT-Gold test results and were thus excluded from the kappa analysis.

RESULTS

Based on an induration of 10 mm in diameter as the TST cutoff value, the QFT-Gold test and TST demonstrated 75.0% agreement (κ = 0.23) in patients with RA and 75.9% agreement (κ = 0.19) in healthy controls. Among the 56 patients with RA who had negative TST results, 11 patients (17.2%) also yielded indeterminate QFT-Gold results.

CONCLUSIONS

Our study showed poor agreement between the results of the QFT-Gold test and the TST in both RA patients and healthy controls. Based on these findings, we emphasize the importance of making clinical decisions in the diagnosis of latent tuberculosis in Koreans with or without RA.

Interferon γ in patients with HIV/AIDS and suspicion or latent tuberculosis infection

OBJECTIVE

To assess the usefulness of IGRA test (QuantiFERON(®)-Cell mediated immune) compared with the tuberculin skin test.

METHODS

A cross-sectional study was carried out in Mexico, 25 infected patients with HIV-AIDS and the suspicion or with latent tuberculous infection (LTBI) who were >18 years of age and without treatment for tuberculosis (TB), were enrolled in the study.

RESULTS

Median cluster of differentiation (CD4) count was 364 cells/μ L and median HIV viral load was 50 copies/mL. Overall, 20 patients (80%) had at least one positive diagnostic test for LTBI: four (16%) had a positive tuberculin skin test and 19 (76%), a positive QuantiFERON(®)-tuberculosis.

CONCLUSIONS

No agreement is found between the two diagnostic tests: k = -0.004, 95% confidence interval (-0.2219, 0.2210). Additional longitudinal studies among HIV-infected populations with high prevalence of TB are needed to further assess the usefulness of IGRAs in this patient population.