Consensus Document on Prevention and Treatment of Tuberculosis in Patients for Biological Treatment

Dual latent tuberculosis screening with tuberculin skin tests and QuantiFERON-TB assays before TNF-α inhibitor initiation in children in Spain

Tumor-necrosis-factor-α inhibitors (anti-TNF-α) are associated with an increased risk of tuberculosis (TB) disease, primarily due to reactivation of latent TB infection (LTBI). We assessed the performance of parallel LTBI screening with tuberculin skin test (TST) and QuantiFERON-TB Gold In-Tube assays (QFT-GIT) before anti-TNF-α treatment in children with immune-mediated inflammatory disorders in a low TB-burden setting. We conducted a multicenter cohort study involving 17 pediatric tertiary centers in Spain. LTBI was defined as the presence of a positive TST and/or QFT-GIT result without clinical or radiological signs of TB disease. A total of 270 patients (median age:11.0 years) were included, mainly with rheumatological (55.9%) or inflammatory bowel disease (34.8%). Twelve patients (4.4%) were diagnosed with TB infection at screening (LTBI, n = 11; TB disease, n = 1). Concordance between TST and QFT-GIT results was moderate (TST+/QFT-GIT+, n = 4; TST-/QFT-GIT+, n = 3; TST+/QFT-GIT-, n = 5; kappa coefficient: 0.48, 95% CI: 0.36-0.60). Indeterminate QFT-GIT results occurred in 10 patients (3.7%) and were associated with young age and elevated C-reactive protein concentrations. Eleven of 12 patients with TB infection uneventfully completed standard LTBI or TB treatment. During a median follow-up period of 6.4 years, only 2 patients developed TB disease (incidence density: 130 (95% CI: 20-440) per 100,000 person-years), both probable de novo infections.

CONCLUSION

A substantial number of patients were diagnosed with LTBI during screening. The dual strategy identified more cases than either of the tests alone, and test agreement was only moderate. Our data show that in children in a low TB prevalence setting, a dual screening strategy with TST and IGRA before anti-TNF-α treatment is effective.

WHAT IS KNOWN

• The optimal screening strategy for latent tuberculosis in children with immune-mediated inflammatory disorders remains uncertain. • Children receiving anti-TNF-α drugs are at increased risk of developing severe tuberculosis disease.

WHAT IS NEW

• A dual screening strategy, using TST and an IGRA assay, identified more children with latent tuberculosis than either of the tests alone. • Identification and treatment of latent tuberculosis before initiation of anti-TNF-α therapy averted incident tuberculosis cases.

Review article: latent tuberculosis in patients with inflammatory bowel diseases receiving immunosuppression-risks, screening, diagnosis and management

BACKGROUND

One quarter of the world's population has latent tuberculosis infection (LTBI). Systemic immunosuppression is a risk factor for LTBI reactivation and the development of active tuberculosis. Such reactivation carries a risk of significant morbidity and mortality. Despite the increasing global incidence of inflammatory bowel disease (IBD) and the use of immune-based therapies, current guidelines on the testing and treatment of LTBI in patients with IBD are haphazard with a paucity of evidence.

AIM

To review the screening, diagnostic practices and medical management of LTBI in patients with IBD.

METHODS

Published literature was reviewed, and recommendations for testing and treatment were synthesised by experts in both infectious diseases and IBD.

RESULTS

Screening for LTBI should be performed proactively and includes assessment of risk factors, an interferon-gamma releasing assay or tuberculin skin test and chest X-ray. LTBI treatment in patients with IBD is scenario-dependent, related to geographical endemicity, travel and other factors. Ideally, LTBI therapy should be used prior to immune suppression but can be applied concurrently where urgent IBD medical treatment is required. Management is best directed by a multidisciplinary team involving gastroenterologists, infectious diseases specialists and pharmacists. Ongoing surveillance is recommended during therapy. Newer LTBI therapies show promise, but medication interactions need to be considered. There are major gaps in evidence, particularly with specific newer therapeutic approaches to IBD.

CONCLUSIONS

Proactive screening for LTBI is essential in patients with IBD undergoing immune-suppressing therapy and several therapeutic strategies are available. Reporting of real-world experience is essential to refining current management recommendations.

Recommendations for prevention of infection in systemic autoimmune rheumatic diseases

OBJECTIVES

To develop recommendations for the prevention of infection in adult patients with systemic autoimmune rheumatic diseases (SARD).

METHODS

Clinical research questions relevant to the objective of the document were identified by a panel of experts selected based on their experience in the field. Systematic reviews of the available evidence were conducted, and evidence was graded according to the Scottish Intercollegiate Guidelines Network criteria. Specific recommendations were made.

RESULTS

Five questions were selected, referring to prevention of infection by Pneumocystis jirovecii with trimethoprim/sulfamethoxazole, primary and secondary prophylactic measures against hepatitis B virus, vaccination against human papillomavirus, vaccination against Streptococcus pneumoniae and vaccination against influenza virus, making a total of 18 recommendations, structured by question, based on the evidence found for the different SARD and/or expert consensus.

CONCLUSIONS

There is enough evidence on the safety and efficacy of vaccinations and other prophylactic measures against the microorganisms reviewed in this document to specifically recommend them for patients with SARD.

[Translated article] Diagnosis of tuberculous infection in immunosuppressed patients and/or candidates for biologics using a combination of 2 IGRA tests: T-SPOT.TB/QuantiFERON TB Gold In-Tube vs. T-SPOT.TB/QuantiFERON TB Gold Plus

INTRODUCTION

The diagnosis of latent tuberculous infection (LTI) by IGRA continues to generate debate. Experience in the simultaneous use of 2 IGRA tests is scant. The aim of this study was to compare the results of 2 versions of QuantiFERON-TB Gold (In-Tube/Plus) with those of T-SPOT.TB, and to analyse the effectiveness of a dual strategy (T-SPOT.TB + QTF) for the diagnosis of LTI in an immunosuppressed population.

METHODS

We conducted a prospective study (May 2015-June 2017) that included 2999 immunosuppressed patients and/or candidates for biologics, in whom 2 simultaneous IGRA tests were performed: Group 1 (1535 patients): T-SPOT.TB + QuantiFERON-TB Gold-In-Tube (QTF-GIT); Group 2 (1464 patients): T-SPOT.TB + QuantiFERON-TB Gold Plus (QTF-Plus.

RESULTS

The concordance between QTF-GIT and T-SPOT.TB was 83.19% (κ = 0.532). The percentage of positive, negative, and indeterminate results were, respectively: 14.33% vs. 17.06%; 82.41% vs. 74.46%; and 3.25% vs. 8.46%. The concordance between QTF-Plus and T-SPOT.TB was 87.56% (κ = 0.609). The percentage of positive, negative, and indeterminate results were, respectively: 15.02% vs. 15.36%; 82.92% vs. 79.37%; and 2.04% vs. 5.25%. Discrepancies between T-SPOT.TB and QTF-Plus were 12.43%, suggesting that 103 patients were positive and another 79 were negative due exclusively to 1 of the 2 IGRAs.

CONCLUSIONS

Greater concordance was found between QTF-Plus and T-SPOT.TB than between QTF-GIT and T-SPOT.TB. However, we believe that the proportion of discrepancies between T-SPOT.TB and QTF-Plus is sufficiently important from a clinical point of view to justify the simultaneous use of 2 IGRA in this specific patient group.

Diagnostic Value of Interferon-Gamma Release Assays for Tuberculosis in the Immunocompromised Population

Interferon-gamma release assays (IGRAs) are widely used in the diagnosis of Mycobacterium tuberculosis (M. tuberculosis) infection by detecting interferon-γ released by previously sensitized T-cells in-vitro. Currently, there are two assays based on either enzyme-linked immunosorbent assay (ELISA) or enzyme-linked immunospot (ELISPOT) technology, with several generations of products available. The diagnostic value of IGRAs in the immunocompromised population is significantly different from that in the immunocompetent population because their results are strongly affected by the host immune function. Both physiological and pathological factors can lead to an immunocompromised situation. We summarized the diagnostic value and clinical recommendations of IGRAs for different immunocompromised populations, including peoplewith physiological factors (pregnant and puerperal women, children, and older people), as well as people with pathological factors (solid organ transplantation recipients, combination with human immunodeficiency virus infection, diabetes mellitus, end-stage renal disease, end-stage liver disease, and chronic immune-mediated inflammatory diseases). Though the performance of IGRAs is not perfect and often requires a combination with other diagnostic strategies, it still has some value in the immunocompromised population. Hopefully, the newly developed IGRAs could better target this population.

Position statement of the Spanish Society of Pediatric Rheumatology on infection screening, prophylaxis, and vaccination of pediatric patients with rheumatic diseases and immunosuppressive therapies: Part 1 (screening)

This study provides practical recommendations on infection screening in pediatric patients with immune-mediated rheumatic diseases and immunosuppressive therapies. For this reason, a qualitative approach was applied. A narrative literature review was performed via Medline. Primary searches were conducted using Mesh and free texts to identify articles that analyzed data on infections and vaccinations in pediatric patients with immune-mediated rheumatic diseases and immunosuppressive therapies. The results were presented and discussed in a nominal group meeting, comprising a committee of 12 pediatric rheumatologists from the infections prevention and treatment working group of the Spanish Society of Pediatric Rheumatology. Several recommendations were generated. A consensus procedure was implemented via a Delphi process that was extended to members of the Spanish Society of Pediatric Rheumatology and Vaccine Advisory Committee of the Spanish Association of Pediatrics. Participants to the process produced a score ranging from 0 = totally disagree to 10 = totally agree. Agreement was considered if at least 70% of participants voted ≥ 7. The literature review included more than 400 articles. Overall, 63 recommendations were generated (21 on infection screening) voted by 59 pediatric rheumatologists and other pediatric specialists, all of them achieving the pre-established agreement level. The recommendations on screening cover all the procedures (serology, assessment of risk factors, and other clinical activities) connected with the screening for infections including tuberculosis; hepatitis A, B, and C viruses; measles; mumps; rubella; diphtheria; and other infections. Conclusion: Screening for infections is an essential part of risk management in pediatric patients with immune-mediated rheumatic diseases and immunosuppressive therapies. What is Known: • Infectious diseases and related complications are a major cause of morbidity and mortality in patients with immune-mediated rheumatic diseases. • At present, practical information on infectious prophylaxis in children with rheumatic diseases is limited, and often extrapolated from children with cancer. What is New: • In the absence of evidence, a literature review and a Delphi survey were conducted to establish a series of expert recommendations that would be useful in clinical practice, providing a practical and simple day-to-day approach to be used by pediatric rheumatologists.

Recommendations for prevention of infection in systemic autoimmune rheumatic diseases

OBJECTIVES

To develop recommendations for the prevention of infection in adult patients with systemic autoimmune rheumatic diseases (SARD).

METHODS

Clinical research questions relevant to the objective of the document were identified by a panel of experts selected based on their experience in the field. Systematic reviews of the available evidence were conducted, and evidence was graded according to the Scottish Intercollegiate Guidelines Network criteria. Specific recommendations were made.

RESULTS

Five questions were selected, referring to prevention of infection by Pneumocystis jirovecii with trimethoprim/sulfamethoxazole, primary and secondary prophylactic measures against hepatitis B virus, vaccination against human papillomavirus, vaccination against Streptococcus pneumoniae and vaccination against influenza virus, making a total of 18 recommendations, structured by question, based on the evidence found for the different SARD and/or expert consensus.

CONCLUSIONS

There is enough evidence on the safety and efficacy of vaccinations and other prophylactic measures against the microorganisms reviewed in this document to specifically recommend them for patients with SARD.

Usefulness of screening tests for diagnosis of latent tuberculosis infection in children

BACKGROUND

The aim of this study is to provide a basis for the development of appropriate screening strategies and evaluate the indications of the interferon-gamma release assay (IGRA) in Bacillus Calmette-Guérin (BCG)-vaccinated children.

METHODS

Children who were examined with both IGRA (QuantiFERON®-TB Gold Plus) and tuberculin skin test (TST) for tuberculosis infection were included in the study. Underlying medical conditions of the patients were recorded. Cohen's κ was run to determine if there was an agreement between TST and IGRA.

RESULTS

A total of 220 patients with a mean age of 11.05 ± 4.43 years (2.5-18 years) were analyzed. Ninety-nine patients were immunocompromised and 121 patients were immunocompetent. TSTs and IGRA showed none to the slight agreement in both of the immunocompromised and immunocompetent patients. In the immunocompromised group, 43/99 (43.4%) and the immunocompetent group 35/121 (28.9%) of the tests did not show any correlation.

CONCLUSION

In a high-risk setting where the BCG vaccine is mandatory, it may be beneficial to use IGRA primarily in immunocompetent patients. In immunocompromised patients, the use of both the TST and IGRA could increase the efficacy of screening for latent tuberculosis infection.

Recommendations of the Spanish Working Group on Crohn's Disease and Ulcerative Colitis (GETECCU) on screening and treatment of tuberculosis infection in patients with inflammatory bowel disease

There is evidence that following the recommendations on screening and treatment of tuberculosis infection does not completely prevent the onset of tuberculosis in patients with inflammatory bowel disease. This fact, and the increasing use of new biologics and immunomodulators, has led the Spanish Group Working on Crohn's Disease and Ulcerative Colitis to update their recommendations for the prevention of tuberculosis in patients with inflammatory bowel disease. Diagnostic methods for latent tuberculosis infection, different scenarios in which screening is to be performed, strategies to reduce the risk of tuberculosis once biological treatment is initiated and chemoprophylaxis guidelines for latent tuberculosis infection are reviewed, as well as the management of active tuberculosis during biological treatment. Finally, there is a summary of the current recommendations within the paper and in an algorithm.

Diagnosis of Tuberculous Infection in Immunosuppressed Patients and/or Candidates for Biologics Using a Combination of 2 IGRA Tests: T-SPOT.TB/QuantiFERON TB Gold In-Tube vs. T-SPOT.TB/QuantiFERON TB Gold Plus

INTRODUCTION

The diagnosis of latent tuberculous infection (LTI) by IGRA continues to generate debate. Experience in the simultaneous use of 2 IGRA tests is scant. The aim of this study was to compare the results of 2 versions of QuantiFERON-TB Gold (In-Tube/Plus) with those of T-SPOT.TB, and to analyse the effectiveness of a dual strategy (T-SPOT.TB + QTF) for the diagnosis of LTI in an immunosuppressed population.

METHODS

We conducted a prospective study (May 2015-June 2017) that included 2,999 immunosuppressed patients and/or candidates for biologics, in whom 2 simultaneous IGRA tests were performed: Group 1 (1535 patients): T-SPOT.TB + QuantiFERON-TB Gold-In-Tube (QTF-GIT); Group 2 (1464 patients): T-SPOT.TB + QuantiFERON-TB Gold Plus (QTF-Plus).

RESULTS

The concordance between QTF-GIT and T-SPOT.TB was 83.19% (κ=0.532). The percentage of positive, negative, and indeterminate results were, respectively: 14.33% vs. 17.06%; 82.41% vs. 74.46%; and 3.25% vs. 8.46%. The concordance between QTF-Plus and T-SPOT.TB was 87.56% (κ=0.609). The percentage of positive, negative, and indeterminate results were, respectively: 15.02% vs. 15.36%; 82.92% vs. 79.37%; and 2.04% vs. 5.25%. Discrepancies between T-SPOT.TB and QTF-Plus were 12.43%, suggesting that 103 patients were positive and another 79 were negative due exclusively to 1 of the 2 IGRAs.

CONCLUSIONS

Greater concordance was found between QTF-Plus and T-SPOT.TB than between QTF-GIT and T-SPOT.TB. However, we believe that the proportion of discrepancies between T-SPOT.TB and QTF-Plus is sufficiently important from a clinical point of view to justify the simultaneous use of 2 IGRA in this specific patient group.

Screening for latent tuberculosis infection in patients with inflammatory bowel disease: Can interferon-gamma release assays replace the tuberculin skin test?

BACKGROUND/AIMS

Screening for latent tuberculosis infection is mandatory before starting anti-tumor necrosis factor therapy. New assays based on interferon-γ (IFN-γ) release have recently become available and may be more accurate. The aim of this study was to compare QuantiFERON-TB and tuberculin skin test in screening for latent infection in patients with inflammatory bowel disease.

MATERIALS AND METHODS

We prospectively screened 138 patients with inflammatory bowel disease for latent tuberculosis infection with chest X-ray, tuberculin skin test, and a third-generation QuantiFERON-TB test. The association of the results in both tests with immunosuppression or inflammatory activity was determined by logistic regression.

RESULTS

The tuberculin skin test and QuantiFERON-TB were positive in 21.7% and 24.6% of the patients, respectively. Overall, 71% patients were receiving immunosuppressants. Concordance between the two tests was moderate (κ=0.59; 95% confidence interval (CI), 0.43-0.75) and was higher in immunosuppressant-naïve patients (κ=0.75; 95% CI, 0.52-0.97) than in immunosuppressed patients (κ=0.51; 95% CI, 0.30-0.72). In both the tests, disease activity and receiving immunosuppression were not associated with the test results. Nevertheless, QuantiFERON-TB was negatively influenced with two or more immunosuppressive drugs.

CONCLUSION

Concordance between the two tests was moderate, and it appears lower with immunosuppression. QuantiFERON-TB alone may be appropriate in immunosuppressant-naïve patients. Both tests should be considered in immunosuppressed patients.

Immune Functional Assays, From Custom to Standardized Tests for Precision Medicine

The immune response is a dynamic system that maintains the integrity of the body, and more specifically fight against infections. However, an unbalanced host immune response is highlighted in many diseases. Exacerbated responses lead to autoimmune and allergic diseases, whereas, low or inefficient responses favor opportunistic infections and viral reactivations. Conflicting situations may also occur, such as in sepsis where inflammation and compensatory immunosuppression make it difficult to deploy the appropriate drug treatment. Until the current day, assessing the immune profile of patients remains a challenge. This is especially due to the inter-individual variability—a key feature of the immune system—which hinders precise diagnosis, prognosis, and therapeutic stratification. Our incapacity to practically interpret the host response may contribute to a high morbidity and mortality, such as the annual 6 million worldwide deaths in sepsis alone. Therefore, there is a high and increasing demand to assess patient immune function in routine clinical practice, currently met by Immune Functional Assays. Immune Functional Assays (IFA) hold a plethora of potentials that include the precise diagnosis of infections, as well as prediction of secondary and latent infections. Current available products are devoted to indirect pathogen detection such as Mycobacteria tuberculosis interferon gamma release assays (IGRA). In addition, identifying the status and the underlying factors of immune dysfunction (e.g., in septic patients) may guide immune targeted therapies. Tools to monitor and stratify the immune status are currently being studied but they still have many limitations such as technical standardization, biomarkers relevance, systematic interpretation and need to be simplified, in order to set the boundaries of “healthy,” “ill,” and “critically ill” responses. Thus, the design of new tools that give a comprehensive insight into the immune functionality, at the bedside, and in a timely manner represents a leap toward immunoprofiling of patients.

Epidemiology and risk factors of asthma-chronic obstructive pulmonary disease overlap in low- and middle-income countries

BACKGROUND

Asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) represents the confluence of bronchial airway hyperreactivity and chronic airflow limitation and has been described as leading to worse lung function and quality of life than found with either singular disease process.

OBJECTIVE

We aimed to describe the prevalence and risk factors for ACO among adults across 6 low- and middle-income countries (LMICs).

METHODS

We compiled cross-sectional data for 11,923 participants aged 35 to 92 years from 4 population-based studies in 12 settings. We defined COPD as postbronchodilator FEV₁/forced vital capacity ratio below the lower limit of normal, asthma as wheeze or medication use in 12 months or self-reported physician diagnosis, and ACO as having both.

RESULTS

The prevalence of ACO was 3.8% (0% in rural Puno, Peru, to 7.8% in Matlab, Bangladesh). The odds of having ACO were higher with household exposure to biomass fuel smoke (odds ratio [OR], 1.48; 95% CI, 0.98-2.23), smoking tobacco (OR, 1.28 per 10 pack-years; 95% CI, 1.22-1.34), and having primary or less education (OR, 1.35; 95% CI, 1.07-1.70) as compared to nonobstructed nonasthma individuals. ACO was associated with severe obstruction (FEV₁ %, <50; 31.6% of ACO vs 10.9% of COPD alone) and severe spirometric deficits compared with participants with asthma (-1.61 z scores FEV₁; 95% CI, -1.48 to -1.75) or COPD alone (-0.94 z scores; 95% CI, -0.78 to -1.10).

CONCLUSIONS

ACO may be as prevalent and more severe in LMICs than has been reported in high-income settings. Exposure to biomass fuel smoke may be an overlooked risk factor, and we favor diagnostic criteria for ACO that include environmental exposures common to LMICs.

Screening and prevention for latent tuberculosis in immunosuppressed patients at risk for tuberculosis: a systematic review of clinical practice guidelines

OBJECTIVE

Immunosuppressed individuals are at a high risk of latent tuberculosis infection (LTBI) and clinical practice guidelines for the screening and management of LTBI in at-risk patients have been developed. We assessed the scope, quality and consistency of clinical practice guidelines on screening for LTBI and the prevention of tuberculosis infection (TB) in high-risk patient populations.

DESIGN

We conducted a systematic review of clinical practice guidelines. Methodological quality of these guidelines was assessed using the Appraisal of Guidelines for Research and Education (AGREE) II instrument. Textual synthesis was used to summarise and compare the recommendations.

DATA SOURCES

Electronic databases (MEDLINE, EMBASE, PsycINFO) and guideline registries were searched from inception to December 2017.

RESULTS

Thirty-eight guidelines were included. Nineteen focused on patients receiving medical immunosuppression, seven on transplantation, three on patients with HIV and nine were generalised across all at risk populations. Most guidelines (n=32, 84%) used a systematic approach to identify and appraise the evidence. The methodological quality of the guidelines varied with the overall mean AGREE II scores ranging from 35% to 80%. Guidelines performed poorly in terms of editorial independence (average score 35%, range 0%-92%); however, most were robust in defining their scope and purpose (average score 80%, range 56%-100%). Guidelines recommended either or both the tuberculin skin test and the interferon gamma release assay for screening. Treatment of LTBI with isoniazid was consistently recommended.

CONCLUSION

Clinical practice guidelines on LTBI vary in quality and scope. The recommendations for screening varied across guidelines, while recommendations for treatment were largely consistent. Improving the consistency and quality of guidelines may help to optimise the screening and management of LTBI for improved patient outcomes.

Screening for Latent Tuberculosis Infection in Patients who are Candidate for Biological Therapies in Spain? A Multidisciplinary Survey

INTRODUCTION

Treatment with biological therapies increases the incidence of tuberculous disease. The introduction of systematic screening for latent tuberculosis infection in patients who are to receive these therapies has reduced this risk. In 2016, the consensus document on the prevention and treatment of tuberculosis in patients who are candidates for biological treatment was published in Spain. The main objective of this study was to evaluate adherence to these guidelines.

METHODS

Multicenter, descriptive, observational study via an anonymous online survey sent to medical societies involved in biologics.

RESULTS

We received 747 responses. Most respondents performed screening at the right time in the right patients (93.7%). Only 36.6% of respondents requested the appropriate diagnostic test, while 56.3% correctly recommended chemoprophylaxis. Up to 96% were familiar with the recommended chemoprophylaxis regimens, while only 63.9% initiated them at the right time. The specialist area that participated most and screened most patients for latent tuberculosis infection was rheumatology (54%). In most cases, pulmonologists were involved in an advisory capacity.

CONCLUSIONS

This study shows poor overall adherence to recommendations, with only 56% of respondents reporting appropriate compliance. The incidence of tuberculous disease in patients who are to receive biological therapies could be reduced further by emphasizing the importance of the right diagnostic test and use of the diagnostic algorithm for latent tuberculosis infection.

High rates of tuberculin skin test positivity due to methotrexate therapy: False positive results?

RATIONALE

The tuberculin skin test (TST) and interferon ? release assays (IGRAs) are commonly used for latent tuberculosis infection (LTBI) screening. Unexpectedly high TST positivity rates have been reported in patients with rheumatic diseases, and methotrexate is frequently used in this population. We hypothesized that methotrexate use could be associated with false-positive TST results.

OBJECTIVES

To investigate whether treatment with methotrexate and other factors are associated with false-positive TST results in patients with rheumatic diseases.

METHODS

Prospective single-center study conducted between April 2013 and March 2016. Adult patients with rheumatic diseases were evaluated with a TST and two IGRAs for LTBI screening. We compared TST and IGRA results in patients treated and not treated with methotrexate and analyzed for factors associated with positive TST results.

CONCLUSIONS

Our data suggest false-positive TST results associated with methotrexate therapy. Thus, we recommend against using the TST for LTBI screening in patients receiving methotrexate and the preferential use of IGRAs in such patients.

MEASUREMENTS AND MAIN RESULTS

We studied 393 patients with rheumatic diseases, including ankylosing spondylitis (ASP, n = 90), rheumatoid arthritis (RA; n = 120), psoriatic arthritis (PA, n = 126), and other disorders (n = 57). The rate of TST positivity varied across the groups: ASP 22.2%, RA 25%, PA 35.7%, and other disorders (22.8%). Positivity rates were lower with IGRAs. Methotrexate use was associated with a statistically significant two-fold increase in the risk of a positive TST and a dose\x96 response relationship was observed. We found no statistically significant associations between methotrexate use and IGRA test positivity.

Tuberculosis associated with tumor necrosis factor-α antagonists, case description and analysis of reported cases in Colombia

Tumor necrosis factor-α (TNF-α) is an important fundamental cytokine during the immune response against cancer and infections such as tuberculosis. This molecule also plays a key pathogenic role in complex and difficult-to-treat diseases such as rheumatoid arthritis, ankylosing spondylitis, Crohn's disease, psoriasis and ulcerative colitis. The treatment of these diseases frequently needs TNF-α antagonists, which has been related to an increased risk of developing tuberculosis, mycoses, and other severe infections.We report the case of a 68-year-old man with Crohn's disease, who developed  disseminated tuberculosis due to anti-TNF-α immunosuppressive therapy. The diagnosis was based on the histopathological findings and molecular biology assays.We discuss the clinical presentation and workup of this case, and we present a comparative analysis of tuberculosis cases associated with anti-TNF-α reported in Colombia during the last 10 years emphasizing on the diagnosis and treatment of latent tuberculosis.

Early Tuberculin Skin Test for the Diagnosis of Latent Tuberculosis Infection in Patients with Inflammatory Bowel Disease

BACKGROUND AND AIM

Sensitivity of tuberculin skin test [TST] during screening for latent tuberculosis infection [LTBI] is affected by steroid and/or immunosuppressant therapy. The aim of this study was to compare performance of the two-step TST in inflammatory bowel disease patients immediately before anti-tumour necrosis factor [TNF] therapy as part of routine screening for LTBI vs control patients when the TST was carried out at an early stage.

METHODS

In this multicentre prospective controlled study, we evaluated the performance of two-step TST with 5-mm threshold. Factors associated with TST results were determined by logistic regression.

RESULTS

We evaluated 243 candidates for anti-TNF therapy and 337 control patients. Overall, 105 patients [18.1%] had an induration ≥ 5 mm in the first TST or in TST retest. LTBI was diagnosed in 25% of patients by TST retest. Twenty-eight [11.5%] anti-TNF group patients vs 77 [22.8%] control patients had a positive TST (odds ratio [OR] 0.44, 95% confidence interval [CI] 0.28-0.70; P < 0.001]. In multivariate analysis, positive TST was associated with higher age [OR 2.63, 95% CI 1.21-5.72; P < 0.001] and 5-aminosalicylate therapy [OR 1.86, 95% CI 1.14-3.05; P = 0.013]. Negative TST was associated with steroid therapy [OR 0.36, 95% CI 0.16-0.83; P = 0.016], immunosuppressant therapy [OR 0.36, 95% CI 0.21-0.62; P < 0.001], or steroids + immunosuppressant therapy [OR 0.20, 95% CI 0.07-0.59; P = 0.004].

CONCLUSIONS

The sensitivity of routine TST performed just before starting anti-TNF therapy is low. TST performed at an early stage enables screening in the absence of immunosuppressive treatment and thus maximises the diagnostic yield of TST for detecting LTBI.