Professional paper

The use of an interferon gamma release assay (IGRA) in the immunodiagnosis of tuberculosis

Brigita Tićac ; Katedra za mikrobiologiju i parazitologiju, Medicinski fakultet Sveučilišta u Rijeci, Rijeka
Jasmina Mahmić ; Katedra za mikrobiologiju i parazitologiju, Medicinski fakultet Sveučilišta u Rijeci, Rijeka
Sandra Barac ; Nastavni zavod za javno zdravstvo Primorsko-goranske županije u Rijeci,
Vojko Rožmanić ; Katedra za pedijatriju, Medicinski fakultet Sveučilišta u Rijeci, Rijeka

Abstract

Aim: Tuberculosis (TB) remains a major global public health problem. Screening for latent tuberculosis infection (LTB) usually involves risk assessment, chest X-ray, the tuberculin skin/PPD (Purified Protein Derivate) test, and/or interferon-gamma release assay (IGRA), according to country-specific guidelines. This paper describes the frequency of application and the results obtained by enzyme-linked immunosorbent IGRA assay for M. tuberculosis. Methods: We conducted a retrospective analysis of the results obtained using Quantiferon-TB Gold In-Tube (QFT-GIT) analysis at the Laboratory for the diagnosis of tuberculosis – Teaching Institute of Public Health County Primorsko-goranska (Croatia). Results: In the seven-year period
(2007–2013) QFT-GIT analysis were processed in 2110 blood samples of patients from different age groups (aged 1 month-95 years; x̄ = 41.9 years; SD = 29.1; mode 56 years). Results were positive in 585 (27.7 %) samples, whereas negative results were found in 1498 (71 %) cases, and in 27 (1.3 %) samples the results were indeterminate. Positive results were distributed equally among males (29 % of 1058 samples) and females (26 % of 1052 samples). Higher incidence of positive results was observed in people over the age of 56, especially in the age group between 81-85 years (61 % of 44 tests). Positive results were most common in the group of hyperreactors (40.5 % of 84 tests) then in TB contacts (35.1 % of 464 tests), as well as health workers (34.9 % of 43 tests). Discussion and Conclusions: Applying in vitro IGRA QFT-GIT test in combination with conventional methods is recognized as a diagnostic method that plays an important role in uncovering LTB and as such represents an important step in prevention of tuberculosis, especially in high-risk groups.

Keywords

interferon-gamma release tests; latent infection; tuberculosis

Hrčak ID:

139476

URI

https://hrcak.srce.hr/139476

Publication date:

1.6.2015.

Article data in other languages: croatian

Visits: 5.242 *