Cost effectiveness of interferon-γ release assay for TB screening of HIV positive pregnant women in low TB incidence countries.

OBJECTIVE

To assess the cost effectiveness for tuberculosis (TB) screening of high-risk human immunodeficiency virus (HIV) positive pregnant women by using interferon-gamma release assays (IGRAs) compared to the tuberculin skin test (TST) in low TB incidence countries.

METHODS

We constructed Markov models using a public health payer perspective. The target population was a hypothetical cohort of 20 year-olds HIV positive pregnant women until age 50 years in three most common screening situations; close contacts, immigrants from high burden countries and occasional screenings. BCG vaccination status was considered. Five strategies; TST, QuantiFERON®-TB Gold In-Tube (QFT), T-SPOT®. TB (T-SPOT), TST followed by QFT and TST followed by T-SPOT were modeled. The main outcome measure of effectiveness was quality-adjusted life-years (QALYs) gained. The incremental cost effectiveness ratio (ICER) of each screening arm was applied and compared.

RESULTS

In the base case analyses of close contacts, T-SPOT yielded the greatest benefits at the lowest cost. In the base case analyses of immigrants and occasional screenings, TST followed by QFT yielded the greatest benefits at the lowest cost.

CONCLUSIONS

Using an IGRA for TB screening of high-risk HIV positive pregnant women is recommended on the basis of the cost effectiveness in low TB incidence countries.