Interferon Gamma Release Assays Based on M. tuberculosis-specific Antigens in Sarcoidosis Patients

Abstract

Interferon gamma release assays based on M. tuberculosis--specific antigens in sarcoidosis patientsTesty oparte na wydzielaniu interferonu gamma pod wpływem antygenów swoistych dla M. tuberculosis u chorych na sarkoidozęThe authors declare no finacial disclosure AbstractIntroduction: This study is a part of the project on interferon gamma release assays performed in the group of untreated sarcoidosis patients formerly BCG vaccinated. The aim of the study was to assess the rate of positive commercial interferon g release assays in sarcoidosis patients. We discussed the results in the context of hypothesis that M. tuberculosis antigens may play a role in the pathogenesis of sarcoidosis. Material and methods: 151 patients, mean age 38 ± 10.3, treatment naive, with newly diagnosed pulmonary sarcoidosis were enrolled into the study. All participants underwent QFT-GIT assay. A subgroup of 81 patients underwent also T-SPOT.TB assay. Results: QFT-GIT was positive in 7/151. T-SPOT.TB was positive in 3/81. There were no indeterminate results in both IGRAs. There was no statistically significant relationship between IGRAs results and sarcoidosis parameters such as the radiologic stage, disease duration and the presence of Löfgren's syndrome. Conclusions: In sarcoidosis patients formerly BCG vaccinated, positive rate of IGRAs was 4.6% for QFT-GIT and 3.7% for T-SPOT. TB. We did not find the influence of the selected parameters of sarcoidosis on IGRAs results. Key words: sarcoidosis, interferon gamma release assays, latent tuberculosis infectionPneumonol Alergol Pol 2015; 83: 126-134 Streszczenie Wstęp: Prezentowana praca jest częścią projektu dotyczącego testów opartych na wydzielaniu interferonu gamma pod wpływem antygenów swoistych dla prątka gruźlicy przeprowadzonego na dużej grupie nieleczonych chorych na sarkoidozę w populacji powszechnie i wielokrotnie szczepionej przeciwko gruźlicy. Celem pracy była ocena wyników testów IGRA w tej grupie chorych. W pracy dyskutowany jest problem przydatności testów IGRA w wykrywaniu zakażenia prątkiem gruźlicy w kontekście współ-cześnie prezentowanych poglądów dotyczących roli antygenów prątka gruźlicy w etiopatogenezie sarkoidozy. Materiał i metody: W badaniu uczestniczyło 151 chorych na sarkoidozę, w wieku 38 ± 10,3 roku, nigdy nieleczonych. Wszyscy uczestnicy badania mieli wykonany test QFT-GIT. Z grupy badanej utworzono podgrupę 81 chorych na sarkoidozę, którym wykonano w tym samym czasie drugi test IGRA: T-SPOT.TB. Wyniki: Dodatni wynik testu QFT-GIT stwierdzono u 7/151 badanych, a wynik testu T-SPOT-TB u 3/81 badanych. Nie stwierdzono wyników nieokreślonych. Nie stwierdzono statystycznie istotnej zależności pomiędzy wynikiem testu IGRA a wybranymi parametrami klinicznymi sarkoidozy. Wnioski: U chorych na sarkoidozę szczepionych w przeszłości przeciwko gruźlicy szczepionką BCG odsetek dodatnich wyników IGRA wynosił 4,6% dla QFT-GIT oraz 3,7% dla T-SPOT.TB. Nie wykazano wpływu wybranych parametrów klinicznych sarkoidozy na wynik testów IGRA.Słowa kluczowe: sarkoidoza, testy opart...

QuantiFERON-TB-GOLD In-Tube in Patients with Sarcoidosis

“…Results obtained by other authors are similar: low incidence of positive results among Danish sarcoidosis patients [11] or high (however, corresponding to high incidence of TB in the studied society) frequency of positive results documented by authors from India [12]. In the study performed by other researchers among Polish, formerly vaccinated sarcoidosis patients, the percentage of positive results was 4.6 when assessed by QFT, and 3.7 when assessed by T-SPOT TB test [13]. Although the percentage of positive outcomes in our sarcoidosis group was slightly higher than in the control group, it well matched the 20.4% prevalence of latent TB reported for Polish blood donors [15].…”

“…The results of already published studies into the use of IGRA tests in the diagnosis of latent TB infection in sarcoidosis patients are not fully conclusive [11][12][13]. Although the authors are concordant as to the fact that positive results are not more frequent than in non-sarcoidosis control subjects, none of these studies provided data on sarcoidosis patients with suspected coexistent tuberculosis on the basis of positive culture results.…”

Simultaneous amplification and testing method forMycobacterium tuberculosisrRNA to differentiate sputum-negative tuberculosis from sarcoidosis

“…In this study, the positive rate of the T-SPOT TB test was 77.8% (7/9) for sputum-negative TB, which was higher than that for sarcoidosis (33.3%, 7/21). Kempisty and colleagues found a lower positive rate (3.7%) of T-SPOT TB in sarcoidosis (15). However, positive T-SPOT TB can still be found in some sarcoidosis patients.…”

Sarcoidosis detected after COVID‑19 with T‑SPOT.TB positive: A case report

“…By contrast, in another study, the sensitivity was reported to be 87.5% whereas the specificity was 86% ( 25 ). In addition, there appeared to be a low rate of T-SPOT.TB positivity in patients with sarcoidosis regardless of the stage, where the possible mechanism may be associated with shared immune response ( 26 ). According to the WHO-consolidated guidelines on tuberculosis, Module 3: Diagnosis-Tests for tuberculosis infection ( 27 ), T-SPOT.TB can be used to test for tuberculosis infection but with exceptionally low certainty of evidence.…”