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

  • Clinical and Epidemiological Study
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Abstract

Purpose

Regular monitoring of latent tuberculosis (TB) infection in healthcare workers (HCWs) is recommended, but the view about the effective method and performance of serial monitoring is controversial. The aim of this study was to determine differences in conversion rates according to TB exposure risk using the tuberculin skin test (TST) and the QuantiFERON-TB Gold In-Tube (QFT-GIT), and to evaluate the reproducibility and within-subject variability of the QFT-GIT in South Korea.

Methods

Fifty-three HCWs were grouped according to their risk for TB exposure: group 1, high risk (n = 21); group 2, low risk (n = 32). Baseline and follow-up TSTs and QFT-GITs were performed from June 2009 to July 2011. Enzyme-linked immunosorbent assays (ELISAs) were repeated for the second QFT-GIT and a third QFT-GIT was performed after 8 weeks when discordant results of the second TST and QFT-GIT or a conversion or reversion were observed.

Results

No difference in the QFT-GIT conversion rate was evident between the two groups (15.4 vs. 6.5 %, p = 0.57), and no TST conversion was observed. The rate of QFT-GIT positivity was higher in the high-risk group (first QFT-GIT: 38.1 vs. 3.1 %, p = 0.002; second QFT-GIT: 33.3 vs. 9.4 %, p = 0.039). The re-test reproducibility of QFT-GIT results was high (100 %), and the within-subject results of repetitive QFT-GITs were variable.

Conclusions

Stricter prevention strategies remain necessary in HCWs at high risk of TB exposure, and serial interferon-γ release assays (IGRAs) should be interpreted with caution in HCWs.

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References

  1. Menzies D, Fanning A, Yuan L, Fitzgerald M. Tuberculosis among health care workers. N Engl J Med. 1995;332:92–8.

    Article  PubMed  CAS  Google Scholar 

  2. Menzies D, Joshi R, Pai M. Risk of tuberculosis infection and disease associated with work in health care settings. Int J Tuberc Lung Dis. 2007;11:593–605.

    PubMed  CAS  Google Scholar 

  3. Jensen PA, Lambert LA, Iademarco MF, Ridzon R; CDC. Guidelines for preventing the transmission of Mycobacterium tuberculosis in health-care settings, 2005. MMWR Recomm Rep. 2005;54:1–141.

    PubMed  Google Scholar 

  4. Sepulveda RL, Ferrer X, Latrach C, Sorensen RU. The influence of Calmette–Guérin bacillus immunization on the booster effect of tuberculin testing in healthy young adults. Am Rev Respir Dis. 1990;142:24–8.

    Article  PubMed  CAS  Google Scholar 

  5. Huebner RE, Schein MF, Bass JB Jr. The tuberculin skin test. Clin Infect Dis. 1993;17:968–75.

    Article  PubMed  CAS  Google Scholar 

  6. Wang L, Turner MO, Elwood RK, Schulzer M, FitzGerald JM. A meta-analysis of the effect of Bacille Calmette Guérin vaccination on tuberculin skin test measurements. Thorax. 2002;57:804–9.

    Article  PubMed  CAS  Google Scholar 

  7. Menzies D. Interpretation of repeated tuberculin tests. Boosting, conversion, and reversion. Am J Respir Crit Care Med. 1999;159:15–21.

    Article  PubMed  CAS  Google Scholar 

  8. Pai M, Zwerling A, Menzies D. Systematic review: t-cell-based assays for the diagnosis of latent tuberculosis infection: an update. Ann Intern Med. 2008;149:177–84.

    Article  PubMed  Google Scholar 

  9. Pai M, Riley LW, Colford JM Jr. Interferon-gamma assays in the immunodiagnosis of tuberculosis: a systematic review. Lancet Infect Dis. 2004;4:761–76.

    Article  PubMed  CAS  Google Scholar 

  10. Menzies D, Pai M, Comstock G. Meta-analysis: new tests for the diagnosis of latent tuberculosis infection: areas of uncertainty and recommendations for research. Ann Intern Med. 2007;146:340–54.

    Article  PubMed  Google Scholar 

  11. Mazurek GH, Jereb J, Vernon A, LoBue P, Goldberg S, Castro K; IGRA Expert Committee; Centers for Disease Control and Prevention (CDC). Updated guidelines for using interferon gamma release assays to detect Mycobacterium tuberculosis infection—United States, 2010. MMWR Recomm Rep. 2010;59:1–25.

    PubMed  Google Scholar 

  12. Ringshausen FC, Nienhaus A, Torres Costa J, Knoop H, Schlösser S, Schultze-Werninghaus G, et al. Within-subject variability of Mycobacterium tuberculosis-specific gamma interferon responses in German health care workers. Clin Vaccine Immunol. 2011;18:1176–82.

    Article  PubMed  CAS  Google Scholar 

  13. van Zyl-Smit RN, Pai M, Peprah K, Meldau R, Kieck J, Juritz J, et al. Within-subject variability and boosting of T-cell interferon-gamma responses after tuberculin skin testing. Am J Respir Crit Care Med. 2009;180:49–58.

    Article  PubMed  Google Scholar 

  14. World Health Organization (WHO). Global tuberculosis control: WHO report 2011. WHO/HTM/TB/2011.16. Geneva, Switzerland: WHO. 2011.

  15. Jo KW, Woo JH, Hong Y, Choi CM, Oh YM, Lee SD, et al. Incidence of tuberculosis among health care workers at a private university hospital in South Korea. Int J Tuberc Lung Dis. 2008;12:436–40.

    PubMed  Google Scholar 

  16. Kim SJ, Lee SH, Kim IS, Kim HJ, Kim SK, Rieder HL. Risk of occupational tuberculosis in National Tuberculosis Programme laboratories in Korea. Int J Tuberc Lung Dis. 2007;11:138–42.

    PubMed  CAS  Google Scholar 

  17. Joint Committee for the Development of Korean Guidelines for Tuberculosis, Korea Centers for Disease Control and Prevention. Korean guidelines for tuberculosis, 1st edition 2011.

  18. Lee KJ, Kang YA, Kim YM, Cho SN, Moon JW, Park MS, et al. Screening for latent tuberculosis infection in South Korean healthcare workers using a tuberculin skin test and whole blood interferon-gamma assay. Scand J Infect Dis. 2010;42:672–8.

    Article  Google Scholar 

  19. American Thoracic Society, CDC. Targeted tuberculin testing and treatment of latent tuberculosis infection. This official statement of the American Thoracic Society was adopted by the ATS Board of Directors, July 1999. This is a Joint Statement of the American Thoracic Society (ATS) and the Centers for Disease Control and Prevention (CDC). This statement was endorsed by the Council of the Infectious Diseases Society of America. (IDSA), September 1999, and the sections of this statement. Am J Respir Crit Care Med. 2000;16:S221–47.

    Google Scholar 

  20. Lee K, Han MK, Choi HR, Choi CM, Oh YM, Lee SD, et al. Annual incidence of latent tuberculosis infection among newly employed nurses at a tertiary care university hospital. Infect Control Hosp Epidemiol. 2009;30:1218–22.

    Article  PubMed  Google Scholar 

  21. Park HY, Jeon K, Suh GY, Kwon OJ, Chung DR, Yoonchang SW, et al. Interferon-gamma release assay for tuberculosis screening of healthcare workers at a Korean tertiary hospital. Scand J Infect Dis. 2010;42:943–5.

    Article  PubMed  Google Scholar 

  22. Skodric-Trifunovic V, Markovic-Denic L, Nagorni-Obradovic L, Vlajinac H, Woeltje KF. The risk of occupational tuberculosis in Serbian health care workers. Int J Tuberc Lung Dis. 2009;13:640–4.

    PubMed  CAS  Google Scholar 

  23. Pai M, Joshi R, Dogra S, Mendiratta DK, Narang P, Kalantri S, et al. Serial testing of health care workers for tuberculosis using interferon-gamma assay. Am J Respir Crit Care Med. 2006;174:349–55.

    Article  PubMed  CAS  Google Scholar 

  24. Hill PC, Brookes RH, Fox A, Jackson-Sillah D, Jeffries DJ, Lugos MD, et al. Longitudinal assessment of an ELISPOT test for Mycobacterium tuberculosis infection. PLoS Med. 2007;4:e192.

    Article  PubMed  Google Scholar 

  25. Park JS, Lee JS, Kim MY, Lee CH, Yoon HI, Lee SM, et al. Monthly follow-ups of interferon-gamma release assays among healthcare workers in contact with TB patients. Chest. 2012. doi:10.1378/chest.11-3299.

    Google Scholar 

  26. Veerapathran A, Joshi R, Goswami K, Dogra S, Moodie EE, Reddy MV, et al. T-cell assays for tuberculosis infection: deriving cut-offs for conversions using reproducibility data. PLoS One. 2008;3:e1850.

    Article  PubMed  Google Scholar 

  27. Detjen AK, Loebenberg L, Grewal HM, Stanley K, Gutschmidt A, Kruger C, et al. Short-term reproducibility of a commercial interferon gamma release assay. Clin Vaccine Immunol. 2009;16:1170–5.

    Article  PubMed  CAS  Google Scholar 

  28. Grindulis H, Baynham MI, Scott PH, Thompson RA, Wharton BA. Tuberculin response two years after BCG vaccination at birth. Arch Dis Child. 1984;59:614–9.

    Article  PubMed  CAS  Google Scholar 

  29. Hadfield JW, Allan J, Windebank WJ. Sensitivity of neonates to tuberculin after BCG vaccination. Br Med J (Clin Res Ed). 1986;292:990–1.

    Article  CAS  Google Scholar 

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The authors declare that they have no conflict of interest.

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Correspondence to Y. A. Kang.

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Kim, S.Y., Park, M.S., Kim, Y.S. et al. Conversion rates of an interferon-γ release assay and the tuberculin skin test in the serial monitoring of healthcare workers. Infection 41, 511–516 (2013). https://doi.org/10.1007/s15010-012-0356-0

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  • DOI: https://doi.org/10.1007/s15010-012-0356-0

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