Incidence of and risk factors for interstitial pneumonia in patients with rheumatoid arthritis in a large Japanese observational cohort, IORRA

The prevalence and risk factors of rheumatoid arthritis-associated interstitial lung disease: a systematic review and meta-analysis

BACKGROUND

Interstitial lung disease (ILD) is the most widespread and fatal pulmonary complication of rheumatoid arthritis (RA). Existing knowledge on the prevalence and risk factors of rheumatoid arthritis-associated interstitial lung disease (RA-ILD) is inconclusive. Therefore, we designed this review to address this gap.

MATERIALS AND METHODS

To find relevant observational studies discussing the prevalence and/or risk factors of RA-ILD, EMBASE, Web of Science, PubMed, and the Cochrane Library were explored. The pooled odds ratios (ORs) / hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated with a fixed/ random effects model. While subgroup analysis, meta-regression analysis and sensitivity analysis were carried out to determine the sources of heterogeneity, the I2 statistic was utilized to assess between-studies heterogeneity. Funnel plots and Egger's test were employed to assess publication bias. Following the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines, our review was conducted.

RESULTS

A total of 56 studies with 11,851 RA-ILD patients were included in this meta-analysis. The pooled prevalence of RA-ILD was 18.7% (95% CI 15.8-21.6) with significant heterogeneity (I2 = 96.4%). The prevalence of RA-ILD was found to be more likely as a result of several identified factors, including male sex (ORs = 1.92 95% CI 1.70-2.16), older age (WMDs = 6.89, 95% CI 3.10-10.67), having a smoking history (ORs =1.91, 95% CI 1.48-2.47), pulmonary comorbidities predicted (HRs = 2.08, 95% CI 1.89-2.30), longer RA duration (ORs = 1.03, 95% CI 1.01-1.05), older age of RA onset (WMDs =4.46, 95% CI 0.63-8.29), positive RF (HRs = 1.15, 95%CI 0.75-1.77; ORs = 2.11, 95%CI 1.65-2.68), positive ACPA (ORs = 2.11, 95%CI 1.65-2.68), higher ESR (ORs = 1.008, 95%CI 1.002-1.014), moderate and high DAS28 (≥3.2) (ORs = 1.87, 95%CI 1.36-2.58), rheumatoid nodules (ORs = 1.87, 95% CI 1.18-2.98), LEF use (ORs = 1.42, 95%CI 1.08-1.87) and steroid use (HRs= 1.70, 1.13-2.55). The use of biological agents was a protective factor (HRs = 0.77, 95% CI 0.69-0.87).

CONCLUSION(S)

The pooled prevalence of RA-ILD in our study was approximately 18.7%. Furthermore, we identified 13 risk factors for RA-ILD, including male sex, older age, having a smoking history, pulmonary comorbidities, older age of RA onset, longer RA duration, positive RF, positive ACPA, higher ESR, moderate and high DAS28 (≥3.2), rheumatoid nodules, LEF use and steroid use. Additionally, biological agents use was a protective factor.

Safety of Tocilizumab on Rheumatoid Arthritis in Patients with Interstitial Lung Disease

Purpose

The prognosis of rheumatoid arthritis (RA) with interstitial lung disease (ILD) is particularly poor. Although drugs that do not contribute to the progression of ILD should be used in RA treatment, none have been established. This study evaluated the safety of tocilizumab in terms of ILD activity.

Patients and Methods

This study prospectively enrolled all 55 patients with RA complicated by ILD who were treated with tocilizumab at Dokkyo Medical University Saitama Medical Center from April 2014 to June 2022. The outcome measures were MMP-3 and KL-6 as biomarkers of RA and ILD activity, respectively, and the relationship between them was analyzed.

Results

Both MMP-3 and KL-6 were significantly improved at 6 months of treatment (P < 0.001 and P < 0.05, respectively), and a weak correlation between MMP-3 and KL-6 was observed (R2 = 0.086, P = 0.087). The group with increased MMP-3 due to RA progression had significantly higher KL-6 at 6 months compared with the group with RA improvement (P < 0.05). Also, the group with ILD progression on computed tomography had significantly higher MMP-3 compared with the groups with improvement or no change of ILD (P < 0.05 and P < 0.01, respectively). The mortality rate was 0% at 6 months, 2.0% at 1 year, 16.7% at 2 years, and 32.4% at 3 years, and mortality from acute exacerbation of ILD due to respiratory infection increased over time.

Conclusion

RA activity and ILD activity were found to be related at 6 months of treatment. Tocilizumab does not seem to affect the mechanism of ILD progression, as most patients showed improvement in both MMP-3 and KL-6 with tocilizumab within 6 months, when this drug would be expected to affect the lungs directly. However, respiratory infection exacerbated ILD from 1 year after the start of treatment. As immunosuppressive drugs, including tocilizumab, have a risk of respiratory infection, it is important to identify early signs of infection.

Impact of interstitial lung disease on clinical remission and unfavourable events of rheumatoid arthritis: results from the IORRA cohort

OBJECTIVES

We aimed to examine the impact of concomitant interstitial lung disease (ILD) on achieving clinical remission and the occurrence of unfavourable clinical events in patients with RA.

METHODS

Among the participants in the Institute of Rheumatology, Rheumatoid Arthritis (IORRA) cohort from 2011 to 2012, patients not achieving remission of 28-joint disease activity score (DAS28) at baseline and those with chest CT images were enrolled. Based on the chest CT images, the patients were divided into two groups: the ILD group and non-ILD group. The associations among the presence of ILD with time to achieving DAS28 remission and development of death, hospitalized infection, major adverse cardiac events (MACE), or malignancy within 5 years were evaluated using time-dependent Cox regression models.

RESULTS

We enrolled 287 patients in the ILD group and 1235 in the non-ILD group. DAS28 remission was achieved at least once in 55.7% and 75.0% of the ILD and non-ILD groups within 5 years, respectively. Presence of ILD was significantly associated with failure to achieve DAS28 remission (adjusted hazard ratio [aHR]: 0.71; 95% CI: 0.58, 0.89). ILD was also a significant factor associated with death (aHR: 3.24; 95% CI: 2.08, 5.03), hospitalized infection (aHR 2.60; 95% CI: 1.77, 3.83), MACE (aHR: 3.40; 95% CI: 1.76, 6.58), and lung cancer (aHR: 16.0; 95% CI: 3.22, 79.2), but not with malignant lymphoma (aHR: 2.27; 95% CI: 0.59, 8.81).

CONCLUSION

Concomitant ILD was a significant factor associated with failure to achieve clinical remission and the occurrence of the unfavourable clinical events in patients with RA.

Clinical characteristics of rheumatoid arthritis patients with interstitial lung disease: baseline data of a single-center prospective cohort

BACKGROUND

To introduce a prospective cohort for rheumatoid arthritis (RA) patients with interstitial lung disease (ILD) and to identify their clinical features in comparison with RA patients without ILD.

METHODS

Using a multidisciplinary collaborative approach, a single-center cohort for RA patients with ILD (RA-ILD) was established in May 2017, and enrolment data from May 2017 to March 2021 were used to compare the clinical features of RA patients without ILD (RA-non ILD). Multivariable logistic regression analysis was used to identify factors associated with ILD in RA patients.

RESULTS

Among 148 RA-ILD and 410 RA-non ILD patients, participants in the RA-ILD group were older (65.8 ± 9.9 vs. 58.0 ± 10.4 years, P < 0.001) and included more males (35.8% vs. 14.6%, P < 0.001) than in the RA-non ILD group. The RA-ILD group had a higher proportion of late-onset RA patients (age ≥ 60 years) than in the comparator group (43.9% vs. 14.2%, P < 0.001). Multivariable logistic regression analysis showed that higher age at RA onset (OR 1.056, 95% CI 1.021-1.091), higher body mass index (BMI; OR 1.65, 95% CI 1.036-2.629), smoking history (OR 2.484, 95% CI 1.071-5.764), and oral glucocorticoid use (OR 3.562, 95% CI 2.160-5.874) were associated with ILD in RA patients, whereas methotrexate use was less likely to be associated with ILD (OR 0.253, 95% CI 0.155-0.412).

CONCLUSIONS

Higher age at RA onset, smoking history, and higher BMI were associated with the presence of ILD among RA patients. Oral glucocorticoids were more frequently used whereas methotrexate was less likely to be used in RA-ILD patients.

Screening criteria for interstitial lung disease associated to rheumatoid arthritis: Expert proposal based on Delphi methodology

OBJECTIVE

To develop a joint proposal for screening criteria of interstitial lung disease (ILD) in patients with rheumatoid arthritis (RA) and vice versa, which serves as a guidelines in patient referral between the Rheumatology and Pneumology departments to early detection of these patients.

METHODS

A systematic literature review was carried out on the risk factors for the development of ILD in RA patients, and for the referral criteria to Rheumatology for suspected early RA. Based on the available evidence, screening criteria were agreed using the Delphi method by a panel of pneumologists and rheumatologists with expertise in these pathologies.

RESULTS

Screening criteria for ILD in patients with RA and for the early detection of RA in cases with ILD of unknown etiology have been developed. In both cases, a detection strategy was based on clinical risk factors. Recommendations also included the complementary tests to be carried out in the different clinical scenarios and on the periodicity that screening should be repeated.

CONCLUSION

A selective screening strategy is recommended for the first time in the early diagnosis of patients with ILD-RA. This multidisciplinary proposal aims to solve some common clinical questions and help decision-making, although its usefulness to identify these patients with good sensitivity must be confirmed in a validation study.

SER-SEPAR recommendations for the management of rheumatoid arthritis-related interstitial lung disease. Part 1: Epidemiology, risk factors and prognosis

OBJECTIVE

To develop multidisciplinary recommendations to improve the management of rheumatoid arthritis-related interstitial lung disease (RA-ILD).

METHODS

Clinical research questions relevant to the objective of the document were identified by a panel of rheumatologists and pneumologists 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 (SIGN) criteria. Specific recommendations were made.

RESULTS

Six PICO questions were selected, three of which analysed the incidence and prevalence of RA-ILD, associated risk factors, and predictors of progression and mortality. A total of 6 specific recommendations on these topics, structured by question, were formulated based on the evidence found and/or expert consensus.

CONCLUSIONS

We present the first official SER-SEPAR document with specific recommendations for RA-ILD management developed to resolve some common clinical questions and facilitate decision-making for patients.

Decision-Making Strategy for the Treatment of Rheumatoid Arthritis-Associated Interstitial Lung Disease (RA-ILD)

Rheumatoid arthritis (RA) is a common type of autoimmune arthritis. Patient clinical outcomes might be influenced by numerous respiratory diseases, but interstitial lung disease (ILD) is the most important comorbidity. RA-associated ILD (RA-ILD) is divided into acute/subacute and chronic forms. In the acute/subacute course, if the disease is severe as indicated by a diffuse alveolar damage pattern, high-dose corticosteroids combined with antimicrobial agents should be promptly initiated while considering the differential diagnoses, primarily acute exacerbation (AE) of RA-ILD, drug-induced pneumonitis, and Pneumocystis pneumonia. As initial therapeutic management in the chronic course, the RA itself should be stabilized without delay; thereafter, the activity of ILD itself can be stabilized, considering the safety of each anti-rheumatic drug. The formation of the usual interstitial pneumonia (UIP) pattern is the most important determinant because lung function can worsen more quickly with this pattern. However, because clinicians can fail to identify specific radiological patterns, it is important to determine whether each patient with RA-ILD has UIP-like lesions such as subpleural reticulation, traction bronchiectasis, and honeycombing especially progressively enlarged cysts. In patients with progressive RA-ILD and high risk for infection or AE of ILD in whom fibrosis is dominant, clinicians should consider starting an anti-fibrotic agent.

Efficacy and safety of abatacept in interstitial lung disease of rheumatoid arthritis: A systematic literature review

BACKGROUND

Interstitial lung disease (ILD) is a serious complication that represents the second leading cause of death in patients with rheumatoid arthritis (RA). Treatment of RA-ILD remains controversial. The absence of randomized clinical trials and specific ACR or EULAR therapeutic guidelines makes it difficult to establish solid therapeutic recommendations on this issue. In this scenario, real-world data is especially valuable.

OBJECTIVE

To review the literature evidence on the efficacy and safety of abatacept (ABA) for the treatment of rheumatoid arthritis (RA) with associated interstitial lung disease (ILD), given its clinical relevance and the lack of consensus on its therapeutic management.

METHODS

PUBMED and EMBASE were searched from the date of approval of ABA to the end of 2020 using a combination of RA, ILD and ABA terms following PRISMA guidelines. Identified studies were evaluated by two independent investigators.

RESULTS

Nine original studies (1 case series and 8 observational studies) were selected for inclusion in the systematic review. No randomized trial or meta-analysis were identified. The mean age of patients ranged from 61.2 to 75 years and the mean RA duration varied from 7.4 to 18 years. Subcutaneous ABA (74.5%-91%) predominated in combination with conventional synthetic DMARDs (csDMARDs) (58%-75%), and it was used as first-line biologic agent in 22.8%-64.9% of the patients. The mean course of ILD ranged from 1 to 6.7 years, being usual and nonspecific interstitial pneumonia the most frequent patterns. Improvement or stabilization of ILD imaging (76.6%-92.7%) and FVC or DLCO (>85%) was described after a mean follow-up of 17.4-47.8 months, regardless of the pattern of lung involvement, being more remarkable in patients with shorter evolution of ILD. ABA led to significantly lower ILD worsening rates than TNF inhibitors (TNFi) and was associated with a 90% reduction in the relative risk of deterioration of ILD at 24 months of follow-up compared to TNFi and csDMARDs. Combination with methotrexate may have a corticoid-sparing effect. No unexpected adverse events were identified.

CONCLUSIONS

Current evidence suggests that ABA may be a plausible alternative to treat RA patients with ILD. It would be highly desirable to develop prospective randomized controlled studies to confirm these findings.

A dose-dependent beneficial effect of methotrexate on the risk of interstitial lung disease in rheumatoid arthritis patients

Objectives

The aim of the study was to assess the influence of different factors, including treatment, on the risk of ILD in the course of RA.

Methods

A total of 109 RA patients were included in the analysis. High-resolution computed tomography (HRCT) of chest was obtained in each patient. Patients were classified as having ILD (ILD group) or not (N-ILD group). The ILD was graded using the semi-quantitative Warrick scale of fibrosis. Warrick extent score (WES) and Warrick severity score (WSS) were calculated separately for each patient, then combined to obtain a global score (WGS).

Results

In univariate analysis the presence of ILD was associated positively with age (P = 5x10^-6) and negatively with MTX treatment (P = 0.0013), mean MTX dose per year of treatment (P = 0.003) and number of DMARDs used (P = 0.046). On multivariate analysis only age and treatment with MTX were independently associated with the presence of ILD. WGS was significantly lower in patients treated with MTX in a dose of ≥15 mg/week (MTX≥15 group) as compared to patients treated with lower doses of MTX (0<MTX<15 group) or not treated with MTX (N-MTX group) (P = 0.04 and P = 0.037, respectively). The ILD prevalence was higher in N-MTX group than in 0<MTX<15 group (P = 0.0036) and MTX≥15 group (0.0007). The difference in ILD prevalence between MTX≥15 and 0<MTX<15 groups was not significant, but the latter group had higher WES (P = 0.044) and trended to have higher WSS and WGS.

Consclusions

We found a beneficial effect of MTX on RA-ILD. Importantly, this effect seems to be dose dependent.

Drug-induced interstitial lung disease in recurrent and/or metastatic head and neck cancer patients treated with cetuximab and/or nivolumab

BACKGROUND

Drug-induced interstitial lung disease (DI-IP) is one of the most serious adverse reactions associated with the use of anticancer drugs. DI-IP prevalence among molecular-targeting drugs and immune checkpoint inhibitors (ICIs) is relatively high in Japanese patients. To assess the risk of cetuximab and/or nivolumab-related IP is important.

PATIENTS AND METHODS

The medical records of 138 patients with recurrent and/or metastatic head and neck squamous cell carcinoma treated with cetuximab-containing chemotherapy and/or nivolumab monotherapy were retrospectively reviewed.

RESULTS

The incidence of DI-IP with R/M HNSCC was 7.2%. DI-IP occurred more frequently in patients treated with cetuximab-containing chemotherapy following nivolumab monotherapy than in patients with other regimens. However, tumor suppression was detected in all patients treated with cetuximab-containing chemotherapy following nivolumab monotherapy, and two achieved a complete response.

CONCLUSIONS

Although patients treated with cetuximab-containing chemotherapy following nivolumab showed dramatic efficacy, careful monitoring should be recommended.

A paradigm shift in studies based on rheumatoid arthritis clinical registries

Clinical research is the study of aspects of patient health or illness that are closely related to clinical practice. In the late 20th and early 21th century, outcomes for patients with rheumatoid arthritis (RA) improved dramatically due to breakthroughs in new drugs. Patient-reported outcome measures now play a significant role in the drug development process as study endpoints in clinical trials of new therapies, and this has led to increased interest in the patient's perspective, drug safety and treatment outcomes in clinical practice. In accordance with these needs, many prospective cohorts for RA patients and registries of biologic disease modifying anti-rheumatic drugs have been actively conducted in the United States and European and Asian countries. A gradual shift is taking place in the major outcomes of clinical research using these prospective cohorts and registries. This article will introduce representative registries for RA in each country set up in the early 2000s and will discuss future perspectives in clinical research on RA patients using such clinical registries.

Association between chest computed tomography findings and respiratory adverse events in rheumatoid arthritis patients undergoing long-term biological therapy

OBJECTIVE

This study aimed to assess the association between chest computed tomography (CT) findings and incidence of respiratory adverse events (RAEs), and to detect risk factors for RAEs, in RA patients treated with long-term biological therapy.

METHODS

Clinical and radiological data of 332 RA patients who were treated with biological disease-modifying antirheumatic drugs were collected. CT data were assessed by an experienced radiologist. Patients were categorized into the interstitial lung disease (ILD) group (n = 29), airway disease (AD) group (n = 76), co-existing ILD and AD (Co-existing) group (n = 6), and the group without detectable change (WDC, n = 221) based on CT findings and scores. The incidence of RAEs was calculated for each group, and risk factors for RAEs from CT findings were explored.

RESULTS

We identified 41 RAEs, including acute onset or exacerbation of ILD (ILD events, n = 15), respiratory tract infection events (infection events, n = 21), and other events (n = 6). Cumulative incidences of ILD events were 20.2, 3.75, 47.2, and 1.94 (/1000 patient-years: PY) in the ILD, AD, Co-existing, and WDC groups, respectively, and those of infection events were 11.3, 17.6, 23.6, and 2.39 (/1000PY), respectively. Severity, as assessed by CT scores, was correlated with the incidence of RAEs. Risk factors for ILD events were reticular and honeycomb changes, and those for infection events were consolidation, bronchial wall thickening, bronchiectasis, bronchiolitis, air trapping, and atelectasis after adjusting for background factors.

CONCLUSION

Our findings highlight particular CT findings that are associated with RAEs in RA patients undergoing long-term biological therapy.

Drug-Induced Interstitial Lung Disease: A Systematic Review

Background: Drug-induced interstitial lung disease (DIILD) occurs as a result of numerous agents, but the risk often only becomes apparent after the marketing authorisation of such agents. Methods: In this PRISMA-compliant systematic review, we aimed to evaluate and synthesise the current literature on DIILD. Results: Following a quality assessment, 156 full-text papers describing more than 6000 DIILD cases were included in the review. However, the majority of the papers were of low or very low quality in relation to the review question (78%). Thus, it was not possible to perform a meta-analysis, and descriptive review was undertaken instead. DIILD incidence rates varied between 4.1 and 12.4 cases/million/year. DIILD accounted for 3–5% of prevalent ILD cases. Cancer drugs, followed by rheumatology drugs, amiodarone and antibiotics, were the most common causes of DIILD. The radiopathological phenotype of DIILD varied between and within agents, and no typical radiological pattern specific to DIILD was identified. Mortality rates of over 50% were reported in some studies. Severity at presentation was the most reliable predictor of mortality. Glucocorticoids (GCs) were commonly used to treat DIILD, but no prospective studies examined their effect on outcome. Conclusions: Overall high-quality evidence in DIILD is lacking, and the current review will inform larger prospective studies to investigate the diagnosis and management of DIILD.

Impact of interstitial lung disease on mortality of patients with rheumatoid arthritis

To identify the prevalence of interstitial lung disease (ILD) in Korean patients with rheumatoid arthritis (RA) and assess its effect on mortality. A total of 3555 patients with RA, with chest X-ray or chest computed tomography (CT) data at enrollment were extracted from the KORean Observational study Network for Arthritis cohort, a nationwide prospective cohort for patients with RA in Korea. The patients were classified into two groups: (1) an ILD group by chest X-ray or chest CT scan, and (2) a non-ILD group by these modalities. After comparing the characteristics of the groups at enrollment, mortalities were compared using the log-rank test. To explore the impact of ILD on mortality, Cox proportional hazard models were used. Sixty-four patients (1.8%) were identified with ILD. Male and older patients were more common in the ILD group. During a mean follow-up of 24 months, 6 patients (9.4%) in the ILD group and 25 patients (0.7%) in the non-ILD group died; the survival rate was significantly worse in the ILD group (p < 0.01). On adjusted analysis, ILD was significantly associated with increased mortality (HR 7.89, CI 3.16-19.69, p < 0.01); the risk of death in patients with ILD was even higher than in patients with cardiovascular disease (CVD, HR 4.10, CI 1.79-9.37, p < 0.01). The prevalence of ILD was 1.8% in Korean patients with RA. ILD is a major risk factor for mortality in patients with RA.

Management of Rheumatoid Arthritis Patients with Interstitial Lung Disease: Safety of Biological Antirheumatic Drugs and Assessment of Pulmonary Fibrosis

Interstitial lung disease (ILD) is one of the major causes of morbidity and mortality of patients with rheumatoid arthritis (RA). Accompanying the increased number of reports on the development or exacerbation of ILD in RA patients following therapy with biological disease-modifying antirheumatic drugs (DMARDs), RA-associated ILD (RA-ILD) has aroused renewed interest. Although such cases have been reported mainly in association with the use of tumor necrosis factor inhibitors, the use of other biological DMARDs has also become a matter of concern. Nevertheless, it is difficult to establish a causative relationship between the use of biological DMARDs and either the development or exacerbation of ILD. Such pulmonary complications may occur in the natural course of RA regardless of the use of biological DMARDs. Since rheumatologists currently aim to achieve remission in RA patients, the administration of biological DMARDs is increasing, even for those with RA-ILD. However, there are no reliable, evidence-based guidelines for deciding whether biological DMARDs can be safely introduced and continued in RA-ILD patients. A standardized staging system for pulmonary conditions of RA-ILD patients is needed when making therapeutic decisions at baseline and monitoring during biological DMARD therapy. Based on the available information regarding the safety of biological DMARDs and the predictive factors for a worse prognosis, this review discusses candidate parameters for risk evaluation of ILD in RA patients who are scheduled to receive biological antirheumatic therapy.

Interstitial lung disease in patients with rheumatoid arthritis: spontaneous and drug induced

Rheumatoid arthritis (RA) is an inflammatory autoimmune disease characterized by the destruction of articular joint structures. RA is a systemic condition that often affects multiple organs, including the heart, lungs, and kidneys. Pulmonary complications of RA are relatively common and include pleural effusion, rheumatoid nodules, bronchiectasis, obliterative bronchiolitis, and opportunistic infections. Interstitial lung disease (ILD) is a common occurrence in patients with RA, and can range in severity from an asymptomatic incidental finding to a rapidly progressing life-threatening event. Usual interstitial pneumonia and non-specific interstitial pneumonia are the two most common patterns, though others have been reported. Various disease-modifying anti-rheumatic drugs-in particular, methotrexate and the tumor necrosis factor-alpha inhibitors-have been associated with RA-ILD in numerous case reports and case series, though it is often difficult to distinguish association from causality. Treatment for RA-ILD typically involves the use of high-dose corticosteroids, often in conjunction with alternative immunosuppressant agents such as azathioprine or mycophenolate mofetil, and outcomes vary widely depending on the initial pattern of lung disease. Additional research into the mechanisms driving RA-ILD is needed to guide future therapy.

Genetics of Interstitial Lung Disease: Vol de Nuit (Night Flight)

Interstitial lung disease (ILD) is a chronic, progressive fibrotic lung disease with a dismal prognosis. ILD of unknown etiology is referred to as idiopathic interstitial pneumonia (IIP), which is sporadic in the majority of cases. ILD is frequently accompanied by rheumatoid arthritis (RA), systemic sclerosis (SSc), polymyositis/dermatomyositis (PM/DM), and other autoimmune diseases, and is referred to as collagen vascular disease-associated ILD (CVD-ILD). Susceptibility to ILD is influenced by genetic and environmental factors. Recent advances in radiographic imaging techniques such as high-resolution computed tomography (CT) scanning as well as high-throughput genomic analyses have provided insights into the genetics of ILD. These studies have repeatedly revealed an association between IIP (sporadic and familial) and a single nucleotide polymorphism (SNP) in the promoter region of the mucin 5B (MUC5B). HLA-DRB1*11 alleles have been reported to correlate with ILD in European patients with SSc, whereas in Japanese patients with RA, the HLA-DR2 serological group was identified. The aim of this review is to describe the genetic background of sporadic IIP, CVD-ILD, drug-induced-ILD (DI-ILD), pneumoconiosis, and hypersensitivity pneumonitis. The genetics of ILD is still in progress. However, this information will enhance the understanding of the pathogenesis of ILD and aid the identification of novel therapeutic targets for personalized medicine in future.

Human leukocyte antigen polymorphisms and personalized medicine for rheumatoid arthritis

Human leukocyte antigen (HLA) polymorphisms are the most important genetic risk factors for rheumatoid arthritis (RA), a chronic systemic inflammatory disease of unknown etiology. Certain HLA-DRB1 alleles, known as shared epitope (SE) alleles because they have the same amino-acid sequence at positions 70-74, are associated with susceptibility to RA. A gene dosage effect is present for RA-predisposing SE alleles, and protective alleles show epistasis. An important role of amino-acid polymorphisms at positions 11 and 13 of the HLA-DRβ chain was also reported recently. Rheumatoid factor and anticitrullinated peptide antibodies are present in many RA patients. Similar to extra-articular manifestations, the presence of these autoantibodies is also associated with certain DRB1 alleles. Different frequencies of RA risk alleles in different ethnicities explain the varying prevalence of RA in different populations and suggest genetic heterogeneity of RA with regard to phenotype and population subsets. Some drug-induced hypersensitivity reactions due to disease-modifying antirheumatic drugs are also associated with HLA alleles. Understanding the role of HLA as the most important genetic factor relevant to RA susceptibility may help in determining its pathogenesis and pave the way to personalized medicine.

Methotrexate-associated Lymphoproliferative Disease with Multiple Pulmonary Nodules in a Patient with Rheumatoid Arthritis

Patients with rheumatoid arthritis (RA) treated with methotrexate (MTX) sometimes develop lymphoproliferative disease (LPD). MTX-associated LPD can affect nodal or extranodal sites, including the gastrointestinal tract, skin, lungs, kidneys and soft tissues, at almost equal frequency. However, it is very rare for MTX-associated LPD to manifest as multiple nodules in the lungs. We herein report the case of a RA patient who developed MTX-associated LPD with multiple pulmonary nodules during a 5-year course of MTX therapy.

Methotrexate: an old new drug in autoimmune disease

Methotrexate (MTX) is currently considered, among disease-modifying anti-rheumatic drugs (DMARDs), the 'anchor-drug' in the treatment of rheumatoid arthritis. In the last 25 years, there has been a marked expansion in the use of MTX in different inflammatory diseases. Its low cost, associated to a good long-term efficacy and safety profile, justifies the use of MTX as a first-line disease-modifying drug or alternatively, a steroid-sparing medication in this field of medicine. Although new emerging options, including biological treatments, are being established in the therapeutic scenario, the good cost/benefit ratio of MTX supports the choice of this drug in combination with these newer therapies, enhancing the efficacy of these combination therapies and decreasing the risk of potential side effects.

The multifaceted aspects of interstitial lung disease in rheumatoid arthritis

Interstitial lung disease (ILD) is a relevant extra-articular manifestation of rheumatoid arthritis (RA) that may occur either in early stages or as a complication of long-standing disease. RA related ILD (RA-ILD) significantly influences the quoad vitam prognosis of these patients. Several histopathological patterns of RA-ILD have been described: usual interstitial pneumonia (UIP) is the most frequent one, followed by nonspecific interstitial pneumonia (NSIP); other patterns are less commonly observed. Several factors have been associated with an increased risk of developing RA-ILD. The genetic background plays a fundamental but not sufficient role; smoking is an independent predictor of ILD, and a correlation with the presence of rheumatoid factor and anti-cyclic citrullinated peptide antibodies has also been reported. Moreover, both exnovo occurrence and progression of ILD have been related to drug therapies that are commonly prescribed in RA, such as methotrexate, leflunomide, anti-TNF alpha agents, and rituximab. A greater understanding of the disease process is necessary in order to improve the therapeutic approach to ILD and RA itself and to reduce the burden of this severe extra-articular manifestation.

Treatment of interstitial lung diseases associated with connective tissue diseases

A variety of interstitial lung diseases (ILDs) have been reported in association with connective tissue diseases (CTDs). ILD is commonly associated with multiple CTDs and accounts for significant morbidity and mortality in these conditions. In rheumatoid arthritis and systemic sclerosis, ILD commonly occurs in the course of these disorders (incidence: 20-44%). The pathological findings of ILDs are similar to those of idiopathic interstitial pneumonia. A wide variety of histopathologic features, such as various types of interstitial pneumonia and airway involvement, have been observed that are specific for ILDs in rheumatoid arthritis, and this high variety makes its pathology complicated. The diagnosis of ILD is generally based on clinical presentation, bronchioalveolar lavage fluid and high-resolution computed tomography, among others. The most important differential diagnosis is infection, especially pneumocystis pneumonia, and treatment-related toxic damage. The immunosuppressive agents most widely used for the treatment of ILDs are cyclophosphamide, azathioprine, mycophenolate mofetil and calcineurin inhibitors. Other therapeutic strategies are currently being extensively studied, such as antifibrotic agents, endothelin-1 receptor antagonists, tyrosine kinase inhibitors and newer biological agents. In this article, we describe novel therapies for ILDs associated with CTDs.