Cited 4 times since 2019 (0.8 per year) source: EuropePMC Journal of clinical tuberculosis and other mycobacterial diseases, Volume 15, 25 4 2019, Pages 100089 Abnormalities suggestive of latent tuberculosis infection on chest radiography; how specific are they? Uzorka JW, Kroft LJM, Bakker JA, van Zwet EW, Huisman E, Prins C, van der Zwan CJ, Ottenhoff THM, Arend SM
Background
Several radiological features have been reported in association with latent tuberculosis infection (LTBI) but it has not been studied which are specific. The aim of this study was to evaluate allegedly characteristic abnormalities on chest radiography (CXR) in patients with LTBI compared to uninfected controls.
Methods
From 236 patients tested with QuantiFERON-TB Gold In-Tube (QFT), the CXR was re-evaluated in a blinded fashion for fibrotic scarring, (non-)calcified nodules and pleural thickening. LTBI was defined as presence of a positive QFT result and/or positive tuberculin skin test result stratified by Bacille Calmette-Guérin-vaccination status.
Results
Any predefined abnormality of LTBI was observed in 116/236 (49.2%) patients, the frequency not being different between groups. However, the specificity for LTBI of a fibrotic scar ≥ 2 cm2 was 100% [95% CI: 92.0%-100%] and of a calcified nodule ≥1.5 mm was 95.7% [95% CI: 85.2%-99.5%]. The frequency of non-calcified nodules and pleural thickening did not differ between groups.
Conclusion
Only a fibrotic scar ≥ 2 cm2 and/or a calcified nodule ≥1.5 mm were significantly associated with LTBI. This finding is clinically relevant mainly in patients who are at significant risk of TB reactivation and in whom indirect diagnostic tests may be unreliable.
