Nontuberculous mycobacterial infection in rheumatoid arthritis patients: a single-center experience in South Korea

Clinical characteristics and prognostic factors of non-tuberculous mycobacterial disease in patients with rheumatoid arthritis

BACKGROUND/AIMS

This study aimed to identify the clinical characteristics of patients with concurrent rheumatoid arthritis (RA) and suspected non-tuberculous mycobacterial (NTM) infections as well as determine their prognostic factors.

METHODS

We retrospectively reviewed the medical records of 91 patients with RA whose computed tomography (CT) findings suggested NTM infection. Subsequently, we compared the clinical characteristics between patients with and without clinical or radiological exacerbation of NTM-pulmonary disease (PD) and investigated the risk factors for the exacerbation and associated mortality.

RESULTS

The mean age of patients with RA and suspected NTM-PD was 65.0 ± 10.2 years. The nodular/bronchiectatic (NB) form of NTM-PD was the predominant radiographic feature (78.0%). During follow-up, 36 patients (41.9%) experienced a radiological or clinical exacerbation of NTM-PD, whereas 12 patients (13.2%) died. Combined interstitial lung disease (ILD), microbiologically confirmed NTM-PD, and NB with the fibrocavitary (FC) form on chest CT were identified as risk factors for the clinical or radiological exacerbation of NTM-PD. Hydroxychloroquine use was identified as a good prognostic factor. Conversely, history of tuberculosis, ILD, smoking, microbiologically confirmed NTM-PD, and NB with the FC form on chest CT were identified as poor prognostic factors for mortality in suspected NTM-PD.

CONCLUSION

ILD and NB with the FC form on chest CT were associated with NTM-PD exacerbation and mortality. Hydroxychloroquine use may lower the risk of NTM-PD exacerbation. Therefore, radiographic features and presence of ILD should be considered when predicting the prognosis of patients with RA and suspected NTM-PD.

Non-tuberculous mycobacterial infections in patients with end-stage renal disease: Prevalence, risk factors, and mortality

Non-tuberculous mycobacterial (NTM) disease has increased in prevalence in the USA, however, little is known on NTM in the population with end-stage renal disease (ESRD). Thus, we investigated patients with ESRD to determine risk factors for NTM disease and mortality. We queried the United States Renal Data System from 2005 to 2015 using International Classification of Diseases (ICD)-9/ICD-10 codes to identify NTM and risk factors. Logistic regression was used to examine the association of risk factors with NTM and Cox proportional hazards modeling was used to assess the association of NTM with mortality. Of 1,068,634 included subjects, 3232 (0.3%) individuals were identified with any NTM diagnosis. Hemodialysis versus peritoneal dialysis (OR=0.10, 95% CI=0.08 to 0.13) was protective for NTM, whereas black (OR=1.27, 95% CI=1.18 to 1.37) or other race compared with white race (OR=1.39, 95% CI=1.21 to 1.59) increased the risk of NTM. HIV (OR=15.71, 95% CI=14.24 to 17.33), history of any transplant (OR=4.25, 95% CI=3.93 to 4.60), kidney transplant (OR=3.00, 95% CI=2.75 to 3.27), diabetes (OR=1.32, 95% CI=1.23 to 1.43), rheumatologic disease (OR=1.92, 95% CI=1.77 to 2.08), and liver disease (OR=2.09, 95% CI=1.91 to 2.30) were associated with increased risk for NTM diagnosis. In multivariable analysis, there was a significant increase in mortality with any NTM diagnosis (HR=1.83, 95% CI=1.76 to 1.91, p≤0.0001). Controlling for relevant demographic and clinical risk factors, there was an increased risk of mortality associated with any diagnosis of NTM. Early diagnosis and treatment of NTM infection may improve survival in patients with ESRD.

Clinical characteristics of rheumatoid arthritis patients complicated with pulmonary nontuberculous mycobacterial disease: A cross-sectional case series study

OBJECTIVES

Pulmonary nontuberculous mycobacterial disease (pNTM) is a common pulmonary complication of rheumatoid arthritis (RA), but their association has rarely been researched. We aimed to reveal the clinical characteristics of RA with pNTM.

METHODS

Among all the RA patients who visited Tenri hospital from April 2017 to March 2018, we enrolled those fulfilling the 2007 ATS/IDSA diagnostic criteria of pNTM, and sex- and age- matched control group at a ratio of 1:5. Demographic characteristics were compared between the two groups.

RESULTS

Among 865 RA patients, 35 (4.0%) patients were complicated with pNTM. RA patients with pNTM had significantly lower BMI and higher rheumatoid factor (RF) and anti-citrullinated protein antibody (ACPA) positivity. Bronchiectasis was the most frequent lesion, followed by clusters of small nodules, patchy consolidation and cavity. Multivariable logistic regression analysis revealed bronchiectasis as a strong independent associated factor of pNTM. Treatment for pNTM was needed in 14 of the 35 (40%) RA patients with pNTM and sputum negative conversion was accomplished in 11 of the 14 cases (78.6%).

CONCLUSIONS

RA patients with lower BMI, RF/ACPA positivity, and bronchiectasis were associated with pNTM. Treatment for pNTM may attain sputum negative conversion and radiological improvement in patients with RA.

TNF inhibitors increase the risk of nontuberculous mycobacteria in patients with seropositive rheumatoid arthritis in a mycobacterium tuberculosis endemic area

The aim of this study is to examine the impact of tumor necrosis factor inhibitors (TNFI) on nontuberculous mycobacterium (NTM) infection in rheumatoid arthritis (RA) patients in a mycobacterium tuberculosis (MTB) endemic area. We selected 1089 TNFI-treated RA patients and 4356 untreated RA patients using propensity-matching analysis according to age, gender, and Charlson comorbidity index using the Korean National Health Insurance Service database from July 2009 to December 2010. Both groups were followed-up until the end of 2016 to measure the incidence of mycobacterial diseases. The incidence rate of NTM in TNFI-treated RA group was similar to those of MTB (328.1 and 340.9 per 100,000 person-years, respectively). The adjusted hazard ratio (aHR) of NTM for TNFI-treated RA compared to untreated RA was 1.751(95% CI 1.105-2.774). The risk of TNFI-associated NTM in RA was 2.108-fold higher among women than men. The age-stratified effects of TNFI on NTM development were significantly high in RA patients aged 50-65 years (aHR 2.018). RA patients without comorbidities had a higher incidence of NTM following TNFI treatment (aHR 1.742). This real-world, observational study highlights the need to increase awareness of NTM in TNFI-treated RA patients in an MTB endemic area.

Short-term tolerability and effectiveness of methotrexate monotherapy in adult patients with Crohn's disease: a retrospective study

INTRODUCTION

Immunomodulators remain fundamental for the medical treatment of Crohn's disease (CD). Methotrexate (MTX) is widely used as a second-line immunomodulator; however, there is a lack of recent data on MTX monotherapy among the Asian population with CD. Therefore, in this study, we aimed to investigate the tolerability and clinical outcomes of MTX in Korean patients with CD.

METHODS

A retrospective chart review was performed for CD patients treated with MTX monotherapy or in combination with 5-aminosalicylic acid (5-ASA), at the Asan Medical Center, Seoul, South Korea. The tolerability of MTX monotherapy within 6 months was assessed and the clinical effectiveness of MTX was evaluated based on the Crohn's disease activity index (CDAI).

RESULTS

In total, 85 patients were included, of which 29 (34.1%) discontinued MTX due to intolerability during the follow-up. Adverse events (AEs) were reported in 41 (48.2%) patients. The most common AE was gastrointestinal disorders (17/41) and only one patient experienced a serious AE, a systemic infection that required hospitalization. Among the 56 patients who tolerated MTX within 6 months, 44 (65.9%) showed a clinical response. Moreover, no factor was significantly associated with intolerability. The administration method was the only factor significantly associated with a response to MTX (p = 0.041). The adjusted odds ratio of parenteral injection compared to oral administration was 5.68 (95% confidence interval (CI), 1.07-30.08).

CONCLUSION

In this study, one-third of patients were intolerant to MTX; nonetheless, the response rate was as high as 65.9% among tolerant patients. In addition, no significant factors affected intolerability. In terms of the clinical response, parenteral injection could be better than oral administration.

Comparison of latent tuberculosis infection screening strategies before tumor necrosis factor inhibitor treatment in inflammatory arthritis: IGRA-alone versus combination of TST and IGRA

This study aims to compare the latent tuberculosis infection (LTBI) screening strategy of interferon-gamma release assay (IGRA)-alone and in combination with tuberculin skin tests (TSTs) before the initiation of tumor necrosis factor (TNF) inhibitor treatment in patients with inflammatory arthritis. Between January 2011 and June 2017, we enrolled 476 patients who were followed up for ≥1 year after the TNF inhibitor initiation in a tertiary referral center in South Korea. Inflammatory arthritis comprised rheumatoid arthritis in 266 (55.9%) and ankylosing spondylitis in 210 (44.1%) patients. The following strategies were used for LTBI screening during the study period: (i) from January 2011 to October 2014, the combination of TST and QuantiFERON-TB Gold In-Tube (QFT-GIT); (ii) between November 2014 and February 2015, QFT-GIT-alone and (iii) since March 2015, either the combination of TST and QFT-GIT or QFT-GIT-alone depending on the attending physician's choice. We compared the screening strategies of QFT-GIT alone and in combination with TST. Overall, 338 (71.0%) patients received LTBI screening tests using the combination of TST and QFT-GIT, and 138 (29.0%) received QFT-GIT-alone. In addition, the LTBI tests were positive in 159 (47.0%) of 338 patients using the combination tests, and 43.8% (148/338) required LTBI treatment. Meanwhile, the LTBI tests were positive in 32.6% (45/138) of QFT-GIT-alone patients, and 30.4% (42/138) required LTBI treatment. Among 338 patients who received combination tests, 2 patients developed active tuberculosis within 1 year after the TNF inhibitor initiation. Of patients who received QFT-GIT-alone, no patient developed tuberculosis. In conclusion, among patients who received QFT-GIT-alone, the number of patients who required LTBI treatment declined compared to the TST and QFT-GIT combination, and none developed active tuberculosis within 1 year, suggesting that QFT-GIT-alone could be a potential screening strategy for diagnosing LTBI in patients with inflammatory arthritis in South Korea.

The risk of nontuberculous mycobacterial infection in patients with Sjögren's syndrome: a nationwide, population-based cohort study

BACKGROUND

Nontuberculous mycobacterial (NTM) infection in immunocompromized patients is currently a growing health concern, and we aimed to examine the relative risk of NTM infection in patients with Sjögren's syndrome (SS) compared with that in non-SS individuals.

METHODS

We used the 2003-2012 Taiwanese National Health Insurance Research Database to identify 6554 incident SS cases during 2007-2012 and selected 98,310 non-SS controls matched (1:15) for age, gender, and the year of first SS diagnosis date after excluding those who had rheumatoid arthritis or systemic lupus erythematosus.

RESULTS

We identified four NTM-infected patients in the SS group (three in the first year) and nine in the non-SS group (three in the first year). SS patients had a higher incidence rate of NTM infection than that in non-SS individuals (IRR, 7.56; 95% CI, 2.33-24.55), especially during the first year (IRR, 16.05; 95% CI, 3.24-79.51). After adjusting for potential confounders, the risk of NTM infection was not increased in SS patients during the entire follow-up period or during the first year, but the risk increased in SS patients treated with immunosuppressants during the entire follow-up period (HR, 17.77; 95% CI, 4.53-69.61), especially during the first year (HR, 33.33; 95% CI, 4.37-254.23).

CONCLUSION

An increased risk of NTM infection was found in SS patients treated with immunosuppressants during the first year after SS diagnosis.