OBJECTIVES

: Tuberculosis has an important burden of disease in developing countries. The aim of this study was to estimate the prevalence of latent tuberculosis infection (LTBI) in a cohort of patients with rheumatoid arthritis (RA) in a specialized center of excellence.

METHODS

: We conducted a retrospective study to explore the prevalence of LTBI in patients with RA in a single setting located in Bogota, Colombia. Under a Treat to Target model we followed patients diagnosed with RA who received biological and conventional therapy treated in 2017. Patients were tested using tuberculin skin test (TST). Thresholds of this test were defined according to CDC recommendations. We stratified the analysis by sex, type of treatment (conventional and biological therapy) and negative and positive LTBI. Means and standard deviations were reported for continuous variables and categorical variables were presented as percentages.

RESULTS

: We included 329 patients diagnosed with AR who were tested for LTBI, 60,2% were women. Mean age was 67.1 years (standard deviation 10.4). According to the therapy, 77.2% were treated with biological and 22.8% with conventional therapy. As far as diseases were concerned including RA, some comorbidities were assessed at the beginning of the follow-up, showing that 26.4% (87/329) had hypertension, 6.1% (20/329) diabetes mellitus and 6,4% (21/329) Sjogren syndrome. As main result, the prevalence of LTBI in patients was 8.2% (27/329) (295 patients had a negative TST, 12 had a TST from 10mm to 15, and 15 patients had a TST >15mm).

CONCLUSIONS

: This study is one of the first approach in Colombia to estimate the prevalence of latent tuberculosis infection. Our estimation of LTBI prevalence was similar to the findings in other studies. Further attention should be paid to elderly patients who have relatively higher rates of LTBI in developing countries.