No influence of haemodialysis on interferon production in the QuantiFERON-TB Gold-In-Tube test.

BACKGROUND

Immunodeficiency in end-stage renal disease (ESRD) can be aggravated by haemodialysis (HD). This results in an increased incidence of reactivation of tuberculosis (TB) in HD patients. The tuberculin skin test to detect a latent TB infection (LTBI) has its limitations in these patients because of a high rate of false negative results due to anergy of T cells. Data on the influence of HD on the performance of interferon-gamma release assays are limited. The aim of this study was to determine the effect of HD on the performance of the QuantiFERON-TB Gold (QFT-G) assay in ESRD patients before, during and after the HD session.

METHODS

In HD patients older than 18 years without immunosuppressive medication or other immunocompromising conditions, the QFT-G assay was performed just before starting HD, 30 minutes after start and immediately after the finish of the HD session.

RESULTS

Twenty patients were included. No statistically significant differences were found in interferon-gamma production in the nil- and antigen tubes between pre-HD, during and after HD. In 1 patient the predialysis result was indeterminate (one of 60 samples, 1.67%). In all 3 patients with a history of LTBI, the QFT-G test tube results were positive at all time points. In the other 16 patients, all test tubes showed negative results.

CONCLUSIONS

The QFT-G assay could be a useful test for the evaluation of the immunological response against Mycobacterium tuberculosis in HD patients. The time point of blood sampling does not seem to affect the interpretation of test results.