Acute effect of low-flux hemodialysis process on the results of the interferon-gamma-based QuantiFERON®–TB Gold In-Tube test in end-stage renal disease patients.

Screening for latent tuberculosis infection before solid organ transplantation is mandatory, but this is not so easy in uremic patients on hemodialysis (HD) treatment. The newly developed interferon-gamma (IFN-γ)-based QuantiFERON^®–TB Gold In-Tube test (QFT-G) seems to be superior to the other available tests. Objective. To investigate the acute effect of the low-flux HD process on the results of the QFT-G assay. Methods. A total of 56 HD patients participated in this prospective study. They were dialyzed under low-flux HD for at least 1 month before blood sampling for QFT-G assay. This assay was performed before and after the 4-h low-flux HD session. Results. Compared with the pre-dialysis level, there was an obvious reduction in the IFN-γ production level (in response to the TB-antigen cocktails) after the HD process ( P=0.00). The pre-dialysis test result was negative in 21 (37.5%), positive in 33 (58.9%), and indeterminate in 2 (3.6%) patients. One pre-dialysis negative result changed to positive after the HD process. On the other hand, 7 pre-dialysis positive and 2 indeterminate results become negative after HD ( P=0.012). Conclusion. In order to maintain the sensitivity of QFT-G assay in chronic renal failure patients on low-flux HD treatment, it is better to perform the test immediately before (not after) the HD process. [ABSTRACT FROM AUTHOR]