Positive conversion of latent tuberculosis screening in patients with inflammatory bowel disease on antitumor necrosis factor alpha drugs: a systematic review and meta-analysis.

Inflammatory bowel disease (IBD) patients undergoing antitumor necrosis factor-alpha (anti-TNF) therapy are at increased risk of developing tuberculosis (TB), making screening before anti-TNF initiation mandatory. Repeated screening during treatment is not yet recommended because of a lack of studies to support this practice. We aimed to determine the proportion of patients who develop latent TB during anti-TNF therapy. We systematically searched studies from MEDLINE, Embase, and Lilacs, and performed a single-arm meta-analysis investigating the positive conversion rate in IBD patients under anti-TNF therapy with previous negative TB screening. We calculated the combined proportion with 95% confidence interval, using the random-effects model. A P value less than 0.05 was considered statistically significant for subgroup differences. We included 13 studies from nine countries with 1153 patients. The overall positive conversion rate was 9.20%. Portugal had 18.01% of positive conversion, Spain 4.51%, and the USA 1.11%. Tests for subgroup differences were statistically significant for subgroup analysis by country and consistency of test used (performig same test as baseline). Subgroup analyses by continent, study design, or specific test (tuberculin skin test or interferon-gamma release assay) showed no statistical difference. Meta-regression analysis showed a significant positive association between positive conversion and TB incidence. In conclusion, IBD patients on anti-TNF therapy can have a positive conversion rate of 9.20%. Higher conversion rates were seen in European and Asian studies compared with those in the Americas (particularly the USA). TB prevention strategies should, therefore, be individualized and based on geographic location and risk factors.