Evaluation of interferon-gamma release assays in the diagnosis of recent tuberculosis infection in health care workers
Casas, Irma (Universitat Autònoma de Barcelona. Departament de Pediatria, Obstetrícia i Ginecologia i de Medicina Preventiva i Salut Pública)
Latorre, Irene (Institut Germans Trias i Pujol. Hospital Universitari Germans Trias i Pujol)
Esteve Pardo, Ma. Guadalupe (Institut Germans Trias i Pujol. Hospital Universitari Germans Trias i Pujol)
Ruiz-Manzano, Juan (Institut Germans Trias i Pujol. Hospital Universitari Germans Trias i Pujol)
Rodriguez, Dora (Institut Germans Trias i Pujol. Hospital Universitari Germans Trias i Pujol)
Prat, Cristina (Institut Germans Trias i Pujol. Hospital Universitari Germans Trias i Pujol)
García-Olivé, Ignasi (Institut Germans Trias i Pujol. Hospital Universitari Germans Trias i Pujol)
Lacoma, Alicia (Institut Germans Trias i Pujol. Hospital Universitari Germans Trias i Pujol)
Ausina, Vicente (Institut Germans Trias i Pujol. Hospital Universitari Germans Trias i Pujol)
Domínguez, José (Institut Germans Trias i Pujol. Hospital Universitari Germans Trias i Pujol)

Date:	2009
Abstract:	Background: Health care workers (HCWs) are a group at risk of latent tuberculosis infection (LTBI). The aims of this study were to determine IFN-γ response by QuantiFERON-TB GOLD In Tube (QFN-G-IT) and T-SPOT. TB in HCWs, comparing the results with tuberculin skin test (TST); and to analyze the capacity of IFN-γ tests to detect recent versus remote LTBI with a prolonged stimulation test (PST). Methodology/Principal Findings: A total of 147 HCWs were enrolled; 23 of whom were BCG vaccinated. 95 HCWs (64. 6%) had a previous positive TST and were not retested; and 52 HCWs had a previous negative TST or were tested for the first time. When we analysed individuals without previous positive TST, the number of positive results for T-SPOT. TB was 12/52 (23. 1%); and for QFN-G-IT, 9/52 (17. 3%). The global concordance (κ) between T-SPOT. TB and QFN-G-IT with TST was 0. 754 and 0. 929 respectively. Of individuals with previous positive TST, T-SPOT. TB and QFN-G-IT were negative in 51. 6% (49/95) and 62. 1% (59/95) respectively, decreasing the concordance to 0. 321 and 0. 288, respectively. In non-BCG vaccinated HCWs with previous positive TST a positive IFN-γ test was associated with degree of exposure and diameter of TST. PST was performed in 24 HCW with previous positive TST and negative IFN-γ tests. PST was developed in 3 cell cultures stimulated with medium alone, ESAT-6 and CFP-10, respectively. In the third and sixth day of incubation period, part of the supernatants were replaced with complete medium supplemented with (rIL)-2. On day 9, ELISPOT assay was performed. In 14 samples PST was not valid due to not having enough cells. In 8 cases, the response was negative, and in 2 cases positive, suggesting that these patients were infected with Mycobacterium tuberculosis in some point in the past. Conclusions: Both IFN-γ tests showed a similar number of positive results, and concordance between the tests was excellent. None of the tests was affected by prior BCG vaccination. IFN-γ tests are a useful tool for detecting recent infection in HCW population.
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Published in:	PloS one, Vol. 4 Núm. 8 (Aug. 2009) , art. e6686, ISSN 1932-6203

DOI: 10.1371/journal.pone.0006686
PMID: 19701460

9 p, 201.6 KB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Health sciences and biosciences > Institut d'Investigació en Ciencies de la Salut Germans Trias i Pujol (IGTP)
Articles > Research articles
Articles > Published articles