Latent tuberculosis infection in Inflammatory Bowel Disease on the background of immunosuppressive therapy

Abstract

Latent TB infection (LTBI) - persistent non-communicable asymptomatic conditionthat can be transformed into a particular clinical form of TB months oryears later. Until recently the tuberculin skin test (TST) was the only method ofdiagnosis LTBI. Skin sensitivity to tuberculin develops in 2-10 weeks after infection.However, some infected people, including patients with various disordersof the immune system and healthy people, there is no answer to the tuberculintest. Method QuantiFERONR-TB Gold IT is designed to assess the cellularimmune response to stimulation by peptide antigens, mycobacterial proteins(ESAT-6, CFP-10, TB7.7 (p4)). The test is based on the quantification of IFN-c.However, the treatment or conditions that weaken the immune system canpotentially reduce the response to IFN-c. Long-term immunosuppressive therapy, by suppressing the immune system may contribute to reactivation oflatent tbc-infection.OBJECTIVE: to study the frequency of detection of latent tuberculosis in inflammatorybowel disease (IBD) in the presence of the combined long-term immunosuppressivetherapy.MATERIALS AND Methods: We examined 28 patients with chronic IBD constantlyrelapsing, treated at the Department of Pathology TSNIIG intestine, with diseaseduration of 3 years or more, including 15 patients with ulcerative colitis (UC) (8men, 7 women) and 13 - Crohn's disease (CD) (8 men, 5 women). The age ofpatients was 16-70 years, mean age -43, 062, 5 (M6r). The diagnosis was verifieddata of clinical, laboratory, histological, and instrumental methods. Patients, depending on the therapy were divided into 3 groups: group 1 (6 pts.) transplantationmesenchymal stem cells (MSCs) in group 2 (17pts.) - patients who receivedinfliximab in group 3 (5 pts.) - by the standard therapy (5-ASA, steroids and/orimmunosuppressive). To identify LTBI method was used QuantiFERONR-TB Gold IT(Nil Control + TB-antigen mitogen Nil + Nil) were measured in blood plasma ofpatients using ELISA test kits «Cellestis» (Sweden). The result is considered positiveif TB-antigen minus Nil> 0, 35 IU/ml, Mitogen Nil-minus any IU/ml. A negativeresult is provided TB-antigen minus Nil <0, 35 IU / ml, Mitogen minus Nil> 0, 5IU/ml. Statistical data processing was carried out using a computer program«STATISTICA 6.0»Results: Among the 28 patients with IBD on a background of prolonged andcombined immunosuppressive therapy in 6 (21.4%) revealed LTBI average concentrationof TB-antigen was Nil - 2, 461, 3 IU/ml, normal <0.35 IU/ml and theaverage concentration of Mitogen Nil - 7, 7621, 4 IU/ml. Of the 15 patients withUC LTBI detected in 2 (13.3%), with mean concentrations of TB-antigen andmitogen Nil Nil amounted to 0, 8460, 5 IU/ml and 6, 563, 3 IU/ ml. Among the13 patients with BC LTBI detected in 4 (30.7%), average concentrations of TBantigenand mitogen Nil Nil amounted to 3, 261, 9 IU/ml and 8, 361, 6 IU/ml. Inthe group treated with Remicade, from 17 patients revealed LTBI in 4 (23.5%)receiving combination immunosuppressive therapy: 2 patients receiving Remicade+ immunosuppressive and two other steroids, Remicade +the averageconcentration of TB-antigen, they amounted to Nil 3, 261, 9 IU/ml, and the averageconcentration of mitogen Nil was -8, 361, 6 IU/ml. In the group treated withMSCs among the 6 patients LTBI found in one case (16.6%) during therapy withMSCs + steroids, the concentration of TB-antigen Nil in this case was 0.36 IU/mland mitogen Nil-3, 15 IU/ml. In the group receiving standard therapy of5 patients LTBI found in one case (5-ASA+metipred), the concentration of TBantigenwas Nil - 1.33 IU/ml and mitogen Nil - 9, 84 IU/ml. It should be emphasizedthat the latent TB infection was detected predominantly in patients withIBD with a total failure, severe relapsing continuously, with the formation ofhormone-dependent and hormone-against the background of long-term combinedimmunosuppressive therapy. Conclusion: In patients with inflammatory bowel disease latent tuberculosisdetected in 21.4% of cases. This fact should be considered when assigning acombination of prolonged immunosuppressive therapy.