Interferon-gamma release assays as a tool for differential diagnosis of gastrointestinal tuberculosis

In this editorial,we comment on an article published in a recent issue of the World Journal of Clinical Cases.There is a pressing need for reliable tools for diagnosing tuberculosis(TB)of the gastrointestinal tract.Despite advancements in the diagnosis and treatment,TB remains a global health challenge.Ali et al demon-strated that TB may mimic gastrointestinal conditions,such as gastric outlet obstruction,causing a delay in the diagnosis.Furthermore,the latter complication is frequently observed during infections,including Helicobacter pylori,and rarely is related to TB,as in the presented case.In line with this,we think that laboratory tests based on interferon-gamma release assays can be a helpful tool for diagnosing latent TB paced in the gastrointestinal tract.Innovative strategies and approaches for diagnosing latent/active extra pulmonary TB are crucial for establishing the diagnosis early and enhancing treatment strategies to mitigate the global burden of TB.

Performance of QuantiFERON(R)-TB Gold In-Tube assay in children receiving disease modifying anti-rheumatic drugs

Background:To evaluate the performance of theQuantiferon(R)-TB Gold In-Tube (QFT-IT) interferon (IFN)-7 assay for the detection of latent tuberculosis infection (LTBI)in children receiving anti-rheumatic treatment in a tertiary referral hospital of Northern Greece.Methods:A total of 79 consecutive children receiving anti-rheumatic treatment [of which 18 screened prior to antitumor necrosis factor (TNF)-α treatment] were tested using Mantoux tuberculin skin test (TST) and QFT-IT.Association of both tests with risk factors for latent tuberculosis and Bacillus Calmette-Guerin immunization was determined.Influence of age,TNF-α inhibitors,systemic corticosteroids,conventional disease modifying anti-rheumatic drugs (DMARDs) and total duration of therapy on the QFT-IT mitogen-induced response was evaluated.Results:Agreement between TST and QFT-IT results was moderate (k=0.38).Frequency of QFT-IT indeterminate results was low (2.5%).In patients with risk factors for LTBI,the odds of a positive IFN-7 assay was increased by a factor of 27.6 (P=0.002),whereas there was no positive TST.There was a significant difference in the mitogeninduced IFN-7 secretion among various treatments (P=0.038).TNF-α inhibitors were associated with increased mitogen-induced IFN-7 secretion compared to monotherapy with conventional DMARDs (P=0.008).All children screened prior to anti-TNF-a treatment exhibited a negative QFT-IT and no active TB disease was detected during a 2-year follow-up.Conclusions:QFT-IT may be a more reliable test than TST for detection of LTBI in children with rheumatic diseases receiving anti-rheumatic treatment.Drug regimen might influence the mitogen-induced IFN-γ secretion and the effect of TNF-α inhibitors might vary according to the specific agent administered.