Demographics and prevalence of positive QuantiFERON-TB Gold In-Tube test in renal transplant candidates.

BACKGROUND: Latent tuberculosis infection (LTBI) screening prior to solid organ transplantation is standard of care. QuantiFERON-TB Gold In-Tube (QFT-GIT) test is the preferred diagnostic test for renal transplant candidates (RTC). QFT-GIT reversions and the potential delay of living-donor kidney transplantation (LDKT) because of QFT-GIT positivity have not been examined previously in RTC.

METHODS: We evaluated the prevalence of positive QFT-GIT in RTC from January 1 through December 31, 2011. In addition, we examined the demographic and renal disease data differences between QFT-GIT-positive and -negative patients, changes in QFT-GIT results, and positive QFT-GIT results reverting to negative. Lastly, we evaluated if QFT-GIT-positive patients were less likely to undergo LDKT within 6 months of QFT-GIT testing.

RESULTS: In total, 722 RTC were analyzed, 16% of whom had positive QFT-GIT. The QFT-GIT-positive patients were more likely to be older and foreign-born, P < 0.0001. Haitians had the highest prevalence. Of the 119 QFT-GIT-positive patients, 25% had low/intermediate-positive results and were more likely to revert to negative, compared with patients with high-positive QFT-GIT results (50% vs. 0%, P = 0.01). A trend was seen toward fewer QFT-GIT-positive patients undergoing LDKT, compared with QFT-GIT-negative patients (0% vs. 3%, P = 0.09).

CONCLUSIONS: Our high prevalence was likely a result of the high number of foreign-born RTC. Half of our small subset of low/intermediate-positive QFT-GIT patients reverted to negative. QFT-GIT-positive patients were more likely to have their LDKT delayed.