A Summary of Meeting Proceedings on Addressing Variability around the Cut Point in Serial Interferon-γ Release Assay Testing

2013 ◽  
Vol 34 (6) ◽  
pp. 625-630 ◽  
Author(s):  
Charles L. Daley ◽  
Randall R. Reves ◽  
Melodie A. Beard ◽  
Jeffrey Boyle ◽  
Richard B. Clark ◽  
...  
Keyword(s):  
Healthcare Workers ◽  
Interferon Γ ◽  
Treatment Algorithms ◽  
Laboratory Science ◽  
Serial Testing ◽  
Key Stakeholders ◽  
National Guidance ◽  
Research Findings ◽  
Release Assay ◽  
Positive Results

On June 13, 2012, a group of key stakeholders, leaders, and national experts on tuberculosis (TB), occupational health, and laboratory science met in Atlanta, Georgia, to focus national discussion on the higher than expected positive results occurring among low-risk, unexposed healthcare workers undergoing serial testing with interferon-γ release assays (IGRAs). The objectives of the meeting were to present the latest clinical and operational research findings on the topic, to discuss evaluation and treatment algorithms that are emerging in the absence of national guidance, and to develop a consensus on the action steps needed to assist programs and physicians in the interpretation of serial testing IGRA results. This report summarizes its proceedings.

scholarly journals Serial testing with the interferon-γ release assay in Portuguese healthcare workers

2010 ◽  
Vol 84 (4) ◽  
pp. 461-469 ◽  
Author(s):  
José Torres Costa ◽  
Rui Silva ◽  
Raul Sá ◽  
Maria João Cardoso ◽  
Albert Nienhaus
Keyword(s):  
Healthcare Workers ◽  
Interferon Γ ◽  
Serial Testing ◽  
Release Assay

scholarly journals Discordant QuantiFERON-TB Gold Test Results Among US Healthcare Workers With Increased Risk of Latent Tuberculosis Infection: A Problem or Solution?

2008 ◽  
Vol 29 (9) ◽  
pp. 878-886 ◽  
Author(s):  
Nira R. Pollock ◽  
Antonio Campos-Neto ◽  
Suely Kashino ◽  
Danielle Napolitano ◽  
Samuel M. Behar ◽  
...  
Keyword(s):  
Healthcare Workers ◽  
Latent Tuberculosis Infection ◽  
Latent Tuberculosis ◽  
Interferon Γ ◽  
Tuberculosis Infection ◽  
Test Results ◽  
Negative Results ◽  
Increased Risk ◽  
Release Assay ◽  
Positive Results

Objective.In late 2006, our hospital implemented use of the QuantiFERON-TB Gold (QFT-G) assay, a whole-blood interferon-γ release assay, for detection of tuberculosis infection. All newly hired healthcare workers (HCWs) with positive Mantoux tuberculin skin test (TST) results were routinely tested with the QFT-G assay, to take advantage of its higher specificity. We then undertook a quality assurance review to evaluate the QFT-G test results in HCWs with multiple risk factors for latent tuberculosis infection (LTBI).Methods.The clinical records for TST-positive HCWs tested with the QFT-G assay were reviewed. HCWs with 2 or more risk factors commonly associated with LTBI were classified as “increased risk” (IR). IR HCWs who had negative QFT-G test results underwent repeat QFT-G testing and were offered testing with a different interferon-γ release assay (T-SPOT.TB) and with extended T cell stimulation assays.Results.Ofl43 TST-positive HCWs tested with the QFT-G assay, 26 (18%) had positive results, 115 (81%) had negative results, and 2 (1 %) had indeterminate results. Of 82 IR HCWs, 23 (28%) had positive QFT-G test results, and 57 (70%) had negative results. Of the 57 IR HCWs with negative results, 43 underwent repeat QFT-G testing: 41 had negative results again, and 2 had positive results. These 43 HCWs were also offered additional testing with the T-SPOT.TB diagnostic, and 36 consented: 31/36 tested negative, and 5/36 tested positive. Extended assays using the antigens ESAT-6 and CFP-10 confirmed the positive results detected by the overnight assays and yielded positive results for an additional 7/36 (19%) of individuals; strikingly, all 36 HCWs had strongly positive test results with assays using purified protein derivative.Conclusions.The extreme discordance between the results of our clinical diagnostic algorithm and the results of QFT-G testing raises concern about the sensitivity of the QFT-G assay for detection of LTBI in our HCWs. Results of extended stimulation assays suggest that many of our IR HCWs have indeed been sensitized to Mycobacterium tuberculosis. It is possible that the QFT-G assay identifies those at higher reactivation risk rather than all previously infected, but, in the absence of long-term follow-up data, we should interpret negative QFT-G results with some caution.

scholarly journals Comparative Evaluation of Standard E TB-Feron ELISA and QuantiFERON-TB Gold Plus Assays in Patients with Tuberculosis and Healthcare Workers

Diagnostics ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1659
Author(s):  
In Young Yoo ◽  
Jaewoong Lee ◽  
Ae Ran Choi ◽  
Yoon Hee Jun ◽  
Hwa Young Lee ◽  
...  
Keyword(s):  
Healthcare Workers ◽  
Interferon Γ ◽  
Low Risk ◽  
Igra Test ◽  
Kappa Value ◽  
Control And Prevention ◽  
Release Assay ◽  
Positive Results ◽  
Very High ◽  
Negative Conversion

Recently, the American Thoracic Society/Infectious Diseases Society of America/Centers for Disease Control and Prevention advised against performing the interferon-γ-release assay (IGRA) test for individuals with a low risk of TB, and also recommended retesting low-risk individuals with an initial positive IGRA result. However, to evaluate both sensitivity and specificity of available tests, we compared the performance of the Standard E TB-Feron (TBF) and QuantiFERON-TB Gold Plus (QFT-Plus) assays in healthcare workers (HCWs) and tuberculosis (TB) patients. We also retrospectively investigated diabetes mellitus (DM) comorbidity among the enrolled TB patients. We prospectively collected samples from 177 HCWs and 48 TB patients. The TBF and QFT-Plus tests were performed and analyzed according to the manufacturers’ instructions. We also defined IGRA results between 0.2 and 0.7 IU/mL as ‘borderline’. The agreement rate between TBF and QFT-Plus was 92.0% (207/225) with a Cohen’s kappa value of 0.77 (95% CI, 0.68–0.87). While the majority (26/31, 83.9%) of borderline TBF results were in HCWs, the majority (14/19, 73.7%) of borderline QFT-Plus results were in TB patients. Discordant results were found in 18 samples, with TBF-positive/QFT-Plus-negative or indeterminate results in 11 HCWs and seven TB patients. After resampling from 10 HCWs (seven borderline-positive and three positive results, all <1.0), six reverted to negative. The prevalence of DM comorbidity was very high (35.4%). In summary, TBF showed substantial agreement with the QFT-Plus assay but had a higher positivity rate in both HCWs and TB patients. The negative conversion rate was high (60%) among HCWs whose initial (TB Ag-nil) result was <1.0.

Use of a T Cell Interferon-γ Release Assay to Evaluate Tuberculosis Risk in Newly Qualified Physicians in Singapore Healthcare Institutions

2009 ◽  
Vol 30 (9) ◽  
pp. 870-875 ◽  
Author(s):  
C. B. E. Chee ◽  
L. K. Y. Lim ◽  
T. M. Barkham ◽  
D. R. Koh ◽  
S. O. Lam ◽  
...  
Keyword(s):  
Healthcare Workers ◽  
Latent Tuberculosis ◽  
Risk Groups ◽  
Interferon Γ ◽  
Public Hospitals ◽  
High Rate ◽  
Assay Result ◽  
Release Assay ◽  
Baseline Test ◽  
Tuberculosis Risk

Background.Surveillance for latent tuberculosis in high-risk groups such as healthcare workers is limited by the nonspecificity of the tuberculin skin test (TST) in BCG-vaccinated individuals. The Mycobacterium tuberculosis antigen-specific interferon-γ release assays (IGRAs) show promise for more accurate latent tuberculosis detection in such groups.Objective.To compare the utility of an IGRA, the T-SPOT.TB assay, with that of the TST in healthcare workers with a high rate of BCG vaccination.Methods.Two hundred seven medical students from 2 consecutive cohorts underwent the T-SPOT.TB test and the TST in their final year of study. Subjects with negative baseline test results underwent repeat testing after working for 1 year as junior physicians in Singapore's public hospitals.Results.The baseline TST result was an induration 10 mm or greater in diameter in 177 of the 205 students who returned to have their TST results evaluated (86.3%), while the baseline T-SPOT.TB assay result was positive in 9 (4.3%) of the students. Repeat T-SPOT.TB testing in 182 baseline-negative subjects showed conversion in 9 (4.9%). A repeat TST in 18 subjects with baseline-negative TST results did not reveal any TST result conversion.Conclusions.The high rate of positive baseline TST results in our BCG-vaccinated healthcare workers renders the TST unsuitable as a surveillance tool in this tuberculosis risk group. Use of an IGRA has enabled the detection and treatment of latent tuberculosis in this group. Our T-SPOT.TB conversion rate highlights the need for greater tuberculosis awareness and improved infection control practices in our healthcare institutions.

Interferon-γ release assay for tuberculosis screening of healthcare workers at a Korean tertiary hospital

2010 ◽  
Vol 42 (11-12) ◽  
pp. 943-945 ◽  
Author(s):  
Hye Yun Park ◽  
Kyeongman Jeon ◽  
Gee Young Suh ◽  
O Jung Kwon ◽  
Doo Ryeon Chung ◽  
...  
Keyword(s):  
Healthcare Workers ◽  
Tertiary Hospital ◽  
Interferon Γ ◽  
Tuberculosis Screening ◽  
Release Assay

Comparison of interferon-γ release assay and tuberculin test for screening in healthcare workers

2010 ◽  
Vol 16 (2) ◽  
pp. 211-221
Author(s):  
José Torres Costa ◽  
Rui Silva ◽  
Raul Sá ◽  
Maria João Cardoso ◽  
Carla Ribeiro ◽  
...  
Keyword(s):  
Healthcare Workers ◽  
Tuberculin Test ◽  
Interferon Γ ◽  
Release Assay

Rate of Latent Tuberculosis Infection Detected by Occupational Health Screening of Nurses New to a London Teaching Hospital

2009 ◽  
Vol 30 (6) ◽  
pp. 581-584 ◽  
Author(s):  
Priya Khanna ◽  
Vladyslav Nikolayevskyy ◽  
Fiona Warburton ◽  
Elek Dobson ◽  
Francis Drobniewski
Keyword(s):  
Tuberculin Skin Test ◽  
Skin Test ◽  
Latent Tuberculosis Infection ◽  
Latent Tuberculosis ◽  
Interferon Γ ◽  
Tuberculosis Infection ◽  
Release Assay ◽  
Ifn Γ ◽  
Positive Results ◽  
Tuberculosis Prevalence

The prevalence of latent tuberculosis infection in a cohort of nurses new to a London hospital was 7.6% (13 of 171), using an interferon-γ(IFN-γ) release assay, and 16.2% (24 of 148), using the tuberculin skin test. On multivariate analysis, birth in a country with tuberculosis prevalence of more than 40 cases per 100,000 population was associated with positive results of both the IFN-γ release assay and the tuberculin skin test.

Conversion rates of an interferon-γ release assay and the tuberculin skin test in the serial monitoring of healthcare workers

Infection ◽  
2012 ◽  
Vol 41 (2) ◽  
pp. 511-516 ◽  
Author(s):  
S. Y. Kim ◽  
M. S. Park ◽  
Y. S. Kim ◽  
S. K. Kim ◽  
J. Chang ◽  
...  
Keyword(s):  
Tuberculin Skin Test ◽  
Skin Test ◽  
Healthcare Workers ◽  
Interferon Γ ◽  
Conversion Rates ◽  
Release Assay
Sign in / Sign up

Export Citation Format

Share Document