A regression predictive model for QuantiFERON-TB Gold Plus indeterminate results in immunosuppressed patients.

Background: Screening for latent tuberculosis infection using Interferon-Gamma Release Assays is a routine procedure prior to the initiation of anti-tumor necrosis factor (TNF) biotherapy or immunosuppressive therapy. However, indeterminate results are relatively frequent and are an obstacle to treatment initiation.

Aim: The aim of this cross-sectional study was to estimate the frequency of indeterminate QuantiFERON-TB Gold Plus test results in Tunisian patients, and to analyze the potential clinico-biological risk factors associated with these indeterminate results.