Tuberculosis in inflammatory bowel disease patients from a referral center in Salvador-Bahia, Brazil
BACKGROUND: In the last decade, potent immunosuppressive therapy has become the standard treatment for inflammatory bowel disease (IBD).1 However, the increasingly use of immunomodulators associated to biological therapy - especially the inhibitors of tumor necrosis factor alpha (TNF-?) - have considerably increased the cases of tuberculosis (TB) in IBD patients.2,3 Meanwhile, Brazil is a high TB burden country, with 87,000 new cases per year, and the state of Bahia reports more than 3,600 new cases annually.4,5
METHODS: Were included IBD patients under treatment followed at a referral center from August 2017 to July 2018. The IBD was diagnosed according to the guideline criteria of was according to the criteria the European Crohn's and Colitis Organizsation. Diagnosis of latent TB infection (LTBI) was based on tuberculin skin test (TST) induration ? 5mm without evidence of clinically manifested active tuberculosis (TB). The development of active TB, diagnosed during the treatment for inflammatory bowel disease, was based on symptoms, TST,, chest X ray and laboratory finding. In addition, Sstatistical analysies was performed using the statistical software package SPSS version 21.0 for Windows. A p-value less than 0.05 was considered statistically significant.
RESULTS: Of the 302 patients evaluated, 185 were submitted to screening for LTBI and 24 (12.9%) were positive. Of the total sample, eight (2.6%) developed active TB during treatment for IBD. Six cases occurred despite theof negative screening for LTBI and two cases occurred even after chemoprophylaxis with isoniazid. Among 186 UC patients, 4 (2.1%) developed active TB and all cases were pulmonary TB. Two patients were under azathioprine monotherapy (?) with azathioprine and two were using 5-ASA derivatives without immunosuppressant. Among 116 Crohn disease (CD) patients, 4 (3.4%) developed active TB, two cases of pulmonary TB and two cases of pleural TB. All patients with CD who developed active TB were under anti-TNF therapy, two under treatment with infliximab monotherapy and two with adalimumab combotherapy associated with azathioprine. In total, 63 (20.9%) patients were under biological therapy. The frequency of active TB disease among patients exposed to anti-TNF when compared to patients not exposed was 6.3% (4/63) and 1.7% (4/239), respectively, and the difference was significant (p=0,047) between those groups. The median time between initiation of anti-TNF therapy and the diagnosis of TB was 19 months (range: 3.0-45.0).
CONCLUSION(S): The frequency of latent TB in our center is comparable to the frequency described in IBD patients from endemic countries. It was observed a high frequency of active TB in IBD patients under anti-TNF therapy from a reference center in Brazil.
Acknowledgment – Fellowship Program from University of the State of Bahia (PICIN UNEB)
REFERENCES:
1. Van Assche G, Vermeire S, Rutgeerts. Curr Drug Targets 2010; 11: 227–33.
2. Jauregui-Amezaga A, et al. J Crohns Colitis (2013) 7, 208–212
3. Abreu C, et al. J Crohns Colitis (2013) 7, e486–e492.
4. Global tuberculosis report 2017. Geneva: World Health Organization; 2017.
5. Secretaria de Vigilância em Saúde - Ministério da Saúde. Boletim epidemiológico da tuberculose. 2017; 8:1-10.
