[Detection of latent tuberculosis infection in peritoneal dialysis patients: new methods]

The risk for tuberculosis (TB) is increased in patients with chronic renal failure and dialysis. Tuberculin skin test (TST) is the classical diagnostic method for screening despite its low sensitivity. New methods based on interferon-gamma have been developed. The aim of this study was to evaluate if Quantiferon® TB-gold In Tube (QFT-GIT) could be useful in the diagnosis of TB infection in patients on peritoneal dialysis (PD).

Fifty-four patients on PD were included in the study. They were evaluated for latent tuberculosis with QFT-GIT, TST and an assessment by an expert pulmonologist using patient's medical history and x-rays. Agreement between test results was determined.

The prevalence of a positive TST was 29.6% for the first test and 31.5% for the second (booster effect). A positive chest x-ray increased the rate of detection of patients with latent TB infection up to 42.6% and the expert physician's evaluation to 44.4%. The correlation between QFT-GIT and TST was fair (k=0.36; P=.006), as it was between TST and expert physician's evaluation (k=0.257; P=.06).

According to our experience QFT-GIT represents an important advantage in the diagnosis of latent TB infection in chronic renal failure patients on PD. It may complement but not replace TST.