Predictive value of the tuberculin skin test and QuantiFERON-tuberculosis Gold In-Tube test for development of active tuberculosis in hemodialysis patients.

BACKGROUND

Hemodialysis (HD) patients are at increased risk of reactivation of latent tuberculosis infection (LTBI) compared with the general population. QuantiFERON-TB Gold (QFT-G) for LTBI detection is more promising than tuberculin skin test (TST) in HD patients.

AIM

In our study, we evaluated the value of the TST and QFT-G In-Tube (QFG-IT) test in the development of active tuberculosis (TB), in the HD patients, and in healthy controls.

METHODS

The study enrolled 95 HD patients and ninety age-matched, healthy controls. The TST and QFG-IT were performed. All the subjects were followed up 5 years for active TB disease.

RESULTS

Compared to the healthy controls, a high prevalence of LTBI was found in the HD patients by QFG-IT (41% vs. 25%). However, no significant difference was detected by TST (32% vs. 31%). Four HD patients and one healthy control progressed to active TB disease within the 5-year follow-up. For active TB discovered subjects, QFG-IT was positive in all, but TST was positive in two (one patient and one healthy control). In HD patients; sensitivity, specificity, positive and negative predictive values of QFG-IT, and TST for active TB was 100% and 25%, 62% and 67%, 10%, and 3%, and 100% and 95%, respectively. Receiver operating curve analysis revealed that the results are significantly different (P = 0.04).

CONCLUSION

QFG-IT test is a more useful diagnostic method than TST for detecting those who will progress to active TB in HD patients.