Lung changes in rheumatoid arthritis: CT findings

Causal relationship between rheumatoid arthritis and bronchiectasis: a bidirectional mendelian randomization study

BACKGROUND

Epidemiological observational studies have elucidated a correlation between rheumatoid arthritis (RA) and bronchiectasis. However, the causal nature of this association remains ambiguous. To clarify this potential causal linkage, we conducted a two-sample Mendelian randomization (MR) analysis to explore the bidirectional causality between RA and bronchiectasis.

METHODS

Summary statistics for RA and bronchiectasis were obtained from the IEU OpenGWAS database We employed various methods, including inverse variance weighting (IVW), MR-Egger, weighted median, weighted mode, and simple mode, to explore potential causal links between RA and bronchiectasis. Additionally, a series of sensitivity studies, such as Cochran's Q test, MR Egger intercept test, and leave-one-out analysis, were conducted to assess the MR analysis's accuracy further.

RESULTS

In the forward MR analysis, the primary analysis indicated that a genetic predisposition to RA correlated with an increased risk of bronchiectasis in European populations (IVW odds ratio (OR): 1.28, 95% confidence interval (CI): 1.20-1.37, p = 1.18E-13). Comparable results were noted in the East Asian subjects (IVW OR: 1.55, 95% CI: 1.30-1.34, p = 8.33E-07). The OR estimates from the other four methods were consistent with those obtained from the IVW method. Sensitivity analysis detected no evidence of horizontal pleiotropy or heterogeneity. Conversely, in the reverse MR analysis, we found no evidence to support a genetic causality between bronchiectasis and RA in either European or East Asian populations.

CONCLUSION

This study indicates that genetic predisposition to RA correlates with a heightened risk of bronchiectasis in both European and East Asian populations. These results imply that routine screening for bronchiectasis in RA patients could be beneficial, and effective management of RA may contribute to a reduced risk of bronchiectasis. Future research should aim to clarify the underlying mechanisms linking these two conditions.

Assessment of risk factors in patients with rheumatoid arthritis-associated interstitial lung disease

OBJECTIVE

To assess the risk factors for interstitial lung disease (ILD) in patients with rheumatoid arthritis (RA) and to evaluate the association of ILD with the use of methotrexate as well as with joint disease activity.

METHODS

A retrospective, cross-sectional study conducted between March and December 2019 at a tertiary healthcare center, in a follow-up of RA patients who had undergone pulmonary function tests (PFT) and chest computed tomography. We evaluated the tomographic characteristics, such as the presence of ILD and its extension, as well as joint disease activity. Functional measurements, such as forced vital capacity (FVC) and diffusing capacity for carbon monoxide (DLCO), were also assessed. After this, a multivariate logistic regression analysis was applied in order to identify risk factors associated with ILD.

RESULTS

We evaluated 1.233 patients, of which 134 were eligible for this study. The majority were female (89.6%), with a mean age of 61 years old and with a positive rheumatoid factor (86.2%). RA-associated ILD (RA-ILD) was detected in 49 patients (36.6%). We found an association of RA-ILD with age ≥= 62 year, male sex, smoking history and fine crackles in lung auscultation and a decreased DLCO. The indicators of being aged ≥ 62 years old and having moderate or high RA disease activity were both independent factors associated with RA-ILD, with an odds ratio of 4.36 and 3.03, respectively. The use of methotrexate was not associated with a higher prevalence of ILD.

CONCLUSION

Age and RA disease activity are important risk factors associated with RA-ILD. Methotrexate was not associated with the development of RA-ILD in the present study.

Prevalence and risk factors of bronchiectasis in rheumatoid arthritis: A systematic review and meta-analysis

OBJECTIVES

We performed a systematic review and meta-analysis for the prevalence and risk factors of rheumatoid arthritis-related bronchiectasis (RA-BR).

METHODS

We queried PubMed and EMBASE databases to identify published literature related to prevalence and risk factors for RA-BR among patients with RA. Data extraction included study design, country, year, method of RA-BR detection, RA characteristics, numerator of RA-BR cases and denominator of patients with RA, and associations with RA-BR presence. We performed a meta-analysis using random or fixed effects models to estimate the prevalence of RA-BR among RA.

RESULTS

Out of a total of 253 studies, we identified 41 total studies that reported on prevalence (n = 34), risk factors (n = 5), or both (n = 2). The included studies had heterogeneous methods to identify RA-BR. Among the 36 studies reporting prevalence, 608 RA-BR cases were identified from a total of 8569 patients with RA. In the meta-analysis, the pooled overall prevalence of RA-BR among RA was 18.7% (95%CI 13.7-24.3%) using random effects and 3.8% (95%CI 3.3-4.2%) using fixed effects. Among studies that used high-resolution chest computed tomography (HRCT) imaging, the prevalence of RA-BR was 22.6% (95%CI 16.8-29.0%) using random effects. When only considering retrospective studies (n = 12), the pooled prevalence of RA-BR among RA was 15.5% (95%CI 7.5-25.5%); among prospective studies (n = 24), the pooled prevalence was 20.7% (95% CI 14.7-27.4%). Risk factors for RA-BR included older age, longer RA duration, genetics (CFTR and HLA), and undetectable circulating mannose binding lectin (MBL) as a biomarker.

CONCLUSION

In this systematic review and meta-analysis, the prevalence of RA-BR was nearly 20% among studies with HRCT imaging, suggesting that bronchiectasis may be a common extra-articular feature of RA. Relatively few factors have been associated with RA-BR. Future studies should standardize methods to identify RA-BR cases and investigate the natural history and clinical course given the relatively high prevalence among RA.

A causal relationship between rheumatoid arthritis and bronchiectasis? A systematic review and meta-analysis

Rheumatoid arthritis (RA) is a chronic autoimmune disease primarily affecting joints but often also associated with lung involvement such as bronchiectasis (BE). The aim of the present systematic review and meta-analysis is to provide an update on the current evidence regarding the prevalence and association between RA and BE. This systematic review and meta-analysis was performed in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines with literature search using the terms ‘Bronchiectasis AND Rheumatoid Arthritis’ without a date limitation on PubMed during May 2020. A total of 28 studies fulfilled the predefined criteria and were included in the present review, with 19 being cross-sectional studies. Twenty-three studies were included in the meta-analysis. The pooled prevalence estimate was 2.69% (95% CI 1.63–4.42) in clinically defined BE, and 24.9% (95% CI 19.21–31.67) in radiologic disease. Many inconsistencies exist regarding potential risk factors for BE in RA patients such as gender, RA duration and severity, as both negative and positive associations have been reported. Although very little is known about possible causative mechanisms between RA and BE, potential pathways might be antigenic stimulation from pulmonary mucus and/or systemic inflammation from joint disease affecting the lungs. At present, the available evidence of bronchiectasis in patients with RA is insufficient to identify RA-associated risk factors for the development of BE, possibly apart from duration of RA, and, consequently, also to fully explore a possible causal relationship between the two disease. However, the increased prevalence of BE in RA patients warrants further studies to explore the association between RA and BE.

Reinterpreting Evidence of Rheumatoid Arthritis-Associated Interstitial Lung Disease to Understand Etiology

Interstitial Lung Disease (ILD) is a well-known complication of rheumatoid arthritis (RA) which often results in significant morbidity and mortality. It is often diagnosed late in the disease process via descriptive criteria. Multiple subtypes of RA-ILD exist as defined by chest CT and histopathology. In the absence of formal natural history studies and definitive diagnostics, a conventional dogma has emerged that there are two major subtypes of RA-ILD (nonspecific interstitial pneumonia (NSIP) and Usual Interstitial Pneumonia (UIP)). These subtypes are based on clinical experience and correlation studies. However, recent animal model data are incongruous with established paradigms of RA-ILD and beg reassessment of the clinical evidence in order to better understand etiology, pathogenesis, prognosis, and response to therapy. To this end, here we: 1) review the literature on epidemiology, radiology, histopathology and clinical outcomes of the various RAILD subtypes, existing animal models, and current theories on RA-ILD pathogenesis; 2) highlight the major gaps in our knowledge; and 3) propose future research to test an emerging theory of RAILD that posits initial rheumatic lung inflammation in the form of NSIP-like pathology transforms mesenchymal cells to derive chimeric disease, and subsequently develops into frank UIP-like fibrosis in some RA patients. Elucidation of the pathogenesis of RA-ILD is critical for the development of effective interventions for RA-ILD.

Differential diagnoses of fibrosing lung diseases

OBJECTIVES

To describe the challenges inherent in diagnosing fibrosing lung diseases (FLD) on CT imaging and methodologies by which the diagnostic process may be simplified.

METHODS

Extensive searches in online scientific databases were performed to provide relevant and contemporary evidence that describe the current state of knowledge related to FLD diagnosis. This includes descriptions of the utility of a working diagnosis for an individual case discussed in a multidisciplinary team (MDT) setting and challenges associated with the lack of consensus guidelines for diagnosing chronic hypersensitivity pneumonitis.

RESULTS

As well as describing imaging features that indicate the presence of a fibrosing lung disease, those CT characteristics that nuance a diagnosis of the various FLDs are considered. The review also explains the essential information that a radiologist needs to convey to an MDT when reading a CT scan. Lastly, we provide some insights as to the future directions the field make take in the upcoming years.

CONCLUSIONS

This review outlines the current state of FLD diagnosis and emphasizes areas where knowledge is limited, and more evidence is required. Fundamentally, however, it provides a guide for radiologists when tackling CT imaging in a patient with FLD.

ADVANCES IN KNOWLEDGE

This review encompasses advice from recent guideline statements and evidence from the latest studies in FLD to provide an up-to-date manual for radiologists to aid the diagnosis of FLD on CT imaging in an MDT setting.

Undetectable mannose binding lectin is associated with HRCT proven bronchiectasis in rheumatoid arthritis (RA)

Aim

The aim of this study was to ascertain whether mannose binding lectin deficiency is implicated in coexistent rheumatoid arthritis and bronchiectasis and to determine whether undetectable mannose binding lectin confers poorer long-term survival in coexistent rheumatoid arthritis and bronchiectasis or in rheumatoid arthritis in general.

Materials and methods

A retrospective audit was conducted in a rheumatoid arthritis cohort in which mannose binding lectin had been measured by enzyme linked immunosorbent assay from 2007–11. Rheumatoid arthritis patients with physician diagnosed HRCT proven bronchiectasis were recruited during this time and compared to those with uncomplicated rheumatoid arthritis. Survival from disease onset was recorded in October 2018. Kaplan-Meier survival estimates were performed to assess mortality over time in the two groups. Log rank tests were used for equality of survivor functions.

Results

The two groups were demographically comparable. A higher frequency of undetectable mannose binding lectin was observed in coexistent rheumatoid arthritis and bronchiectasis (37.5%) compared to uncomplicated rheumatoid arthritis, (8.9%, P = 0.005). Undetectable mannose binding lectin correlated with a strong trend toward poor survival in rheumatoid arthritis overall (P = 0.057). Cox regression analysis however, showed no difference in the hazard ratio for survival between the two groups when corrected for age, gender, prednisolone use ever, rheumatoid factor status and the full range of MBL concentrations.

Conclusion

In summary, undetectable mannose binding lectin is associated with coexistent rheumatoid arthritis and bronchiectasis and correlates with poor survival in rheumatoid arthritis overall. These findings further implicate immunodeficiency in the genesis of bronchiectasis in rheumatoid arthritis.

Rheumatoid pulmonary nodules: clinical and imaging features compared with malignancy

OBJECTIVES

The objective of this study was to identify clinical and imaging features that distinguish rheumatoid lung nodules from malignancy.

METHODS

We conducted a retrospective review of 73 rheumatoid patients with histologically-proven rheumatoid and malignant lung nodules encountered at Mayo Clinic, Rochester, MN (2001-2016). Medical records and imaging were reviewed including a retrospective blinded review of CT and PET/CT studies.

RESULTS

The study cohort had a mean age of 67 ± 11 years (range 45-86) including 44 (60%) women, 82% with a smoking history, 38% with subcutaneous rheumatoid nodules, and 78% with rheumatoid factor seropositivity. Subjects with rheumatoid lung nodules compared to malignancy were younger (59 ± 12 vs 71 ± 9 years, p < 0.001), more likely to manifest subcutaneous rheumatoid nodules (73% vs 20%, p < 0.001) and rheumatoid factor seropositivity (93% vs 68%, p = 0.034) but a history of smoking was common in both groups (p = 0.36). CT features more commonly associated with rheumatoid lung nodules compared to malignancy included multiplicity, smooth border, cavitation, satellite nodules, pleural contact, and a subpleural rind of soft tissue. Optimal sensitivity (77%) and specificity (92%) (AUC 0.85, CI 0.75-0.94) for rheumatoid lung nodule were obtained with ≥ 3 CT findings (≥ 4 nodules, peripheral location, cavitation, satellite nodules, smooth border, and subpleural rind). Key ¹⁸FDG-PET/CT features included low-level metabolism (SUV_max 2.7 ± 2 vs 7.2 ± 4.8, p = 0.007) and lack of ¹⁸F-fluorodeoxyglucose (FDG)-avid draining lymph nodes.

CONCLUSION

Rheumatoid lung nodules have distinct CT and PET/CT features compared to malignancy. Patients with rheumatoid lung nodules are younger and more likely to manifest subcutaneous rheumatoid nodules and seropositivity.

KEY POINTS

• Rheumatoid lung nodules have distinct clinical and imaging features compared to lung malignancy. • CT features of rheumatoid lung nodules include multiplicity, cavitation, satellite nodules, smooth border, peripheral location, and subpleural rind. • Key PET/CT features include low-level metabolism and lack of FDG-avid draining lymph nodes.

Obliterative bronchiolitis associated with rheumatoid arthritis: analysis of a single-center case series

BACKGROUND

Rheumatoid arthritis (RA) is a systemic autoimmune condition characterized by erosive inflammation of the joints. One rare pulmonary manifestation is obliterative bronchiolitis (OB), a small airways disease characterized by the destruction of bronchiolar epithelium and airflow obstruction.

METHODS

We retrospectively reviewed the clinical data of patients with rheumatoid arthritis-associated obliterative bronchiolitis (RA-OB) from 01/01/2000 to 12/31/2015. Presenting clinical features, longitudinal pulmonary function testing, radiologic findings, and independent predictors of all-cause mortality were assessed.

RESULTS

Forty one patients fulfilled criteria for diagnosis of RA-OB. There was notable female predominance (92.7%) with a mean age of 57 ± 15 years. Dyspnea was the most common presenting clinical symptom. Median FEV1 was 40% (IQR 31-52.5) at presentation, with a mean decline of - 1.5% over a follow-up period of thirty-three months. Associated radiologic findings included mosaic attenuation and pulmonary nodules. A majority of patients (78%) received directed therapy including long-acting inhalers, systemic corticosteroids or other immunosuppressive agents, and macrolide antibiotics. All-cause mortality was 27% over a median follow-up of sixty-two months (IQR 32-113). No distinguishable predictors of survival at presentation were found.

CONCLUSIONS

RA-OB appears to have a stable clinical course in the majority of patients despite persistent symptoms and severe obstruction based on presenting FEV1.

Is Male Rheumatoid Arthritis an Occupational Disease? A Review

Background:

Rheumatoid arthritis (RA) is a systemic, inflammatory disease with an estimated global prevalence of 0.3–1.0%. An unexplained association exists between low formal education and the development of RA independent of smoking. It is established that RA is initiated in the lungs and that various occupations associated with dust, fume and metal inhalation can increase the risk of RA development.

Objective:

The objective of this review is to evaluate published clinical reports related to occupations associated with RA development. We highlight the concept of a “double-hit” phenomenon involving adsorption of toxic metals from cigarette smoke by dust residing in the lung as a result of various work exposures. We discuss the relevant pathophysiological consequences of these inhalational exposures in relation to RA associated autoantibody production.

Method:

A thorough literature search was performed using available databases including Pubmed, Embase, and Cochrane database to cover all relative reports, using combinations of keywords: rheumatoid arthritis, rheumatoid factor, anti-citrullinated peptide antibody silica, dust, fumes, metals, cadmium, cigarette smoking, asbestos, mining, bronchial associated lymphoid tissue, heat shock protein 70, and adsorption.

Conclusion:

We postulate that the inhalation of dust, metals and fumes is a significant trigger factor for RA development in male patients and that male RA should be considered an occupational disease. To the best of our knowledge, this is the first review of occupations as a risk factor for RA in relation to the potential underlying pathophysiology.

Interstitial Lung Diseases

The term interstitial lung diseases (ILD) comprises a diverse group of diseases that lead to inflammation and fibrosis of the alveoli, distal airways, and septal interstitium of the lungs. The ILD consist of disorders of known cause (e.g., collagen vascular diseases, drug-related diseases) as well as disorders of unknown etiology. The latter include idiopathic interstitial pneumonias (IIPs), and a group of miscellaneous, rare, but nonetheless interesting, diseases. In patients with ILD, MDCT enriches the diagnostic armamentarium by allowing volumetric high-resolution scanning, i.e., continuous data acquisition with thin collimation and a high spatial frequency reconstruction algorithm. CT is a key method in the identification and management of patients with ILD. It not only improves the detection and characterization of parenchymal abnormalities, but also increases the accuracy of diagnosis. The spectrum of morphologic characteristics that are indicative of interstitial lung disease is relatively limited and includes the linear and reticular pattern, the nodular pattern, the increased attenuation pattern (such as ground-glass opacities and consolidation), and the low attenuation pattern (such as emphysema and cystic lung diseases). In the correct clinical context, some patterns or combination of patterns, together with the anatomic distribution of the abnormality, i.e., from the lung apex to the base, or peripheral subpleural versus central bronchovascular, can lead the interpreter to a specific diagnosis. However, due to an overlap of the CT morphology between the various entities, the final diagnosis of many ILD requires close cooperation between clinicians and radiologists and complementary lung biopsy is recommended in many cases.

Lung involvement in inflammatory rheumatic diseases

This chapter describes the involvement of the lung in systemic inflammatory joint disease (IJD) with a particular focus on rheumatoid arthritis, although the topics of pulmonary involvement in ankylosing spondylitis and psoriatic arthritis are also addressed. Interstitial lung disease is the most lethal pulmonary complication of IJD and the chapter describes recent advances in both our understanding of this complication and the therapeutic options that offer real hope for improved outcomes. Although less well recognised, airways disease is just as common and its association with IJD is described in some detail, with a section devoted to the recent surge in interest in bronchiectasis. Acute pulmonary infection is common in IJD and its management is reviewed in some detail. Although pleural disease is less common than it once was, its treatment is explored. We conclude by reviewing the relationship between the drug therapies employed in IJD and their effects on the lung.

State-of-the-Art Imaging of the Lung for Connective Tissue Disease (CTD)

Involvement of the respiratory system is common in connective tissue diseases (CTDs), and the resultant lung injury can affect every part of the lung: the pleura, alveoli, interstitium, vasculature, lymphatic tissue, and large and/or small airways. Most of the parenchymal manifestations of CTD are similar to those found in interstitial lung diseases (ILDs), especially idiopathic interstitial pneumonias, and can be classified using the same system. Although there is some overlap, each CTD is associated with a characteristic pattern of pulmonary involvement. For this reason, thin-section CT as well as pulmonary function tests and serum markers are utilized for diagnosis, disease severity assessment, and therapeutic efficacy evaluation of ILD associated with CTD. In addition, newly developed pulmonary magnetic resonance imaging (MRI) procedures have been recommended as useful alternative imaging options for patients with CTD. This review article will (1) address radiological findings for chest radiography and conventional or thin-section CT currently used for six major types of CTD, rheumatoid arthritis, scleroderma (progressive systemic sclerosis), polymyositis/dermatomyositis, systemic lupus erythematosus, Sjögren syndrome and mixed connective tissue disease; (2) briefly deal with radiation dose reduction for thin-section CT examination; and (3) discuss clinically applicable or state-of-the-art MR imaging for CTD patients.

Thin-section chest CT findings in polymyalgia rheumatica: a comparison between with and without rheumatoid arthritis

We retrospectively compared the thin-section chest computed tomography (CT) findings between 25 patients of polymyalgia rheumatica (PMR) with rheumatoid arthritis (RA) and 29 patients of PMR without RA. PMR patients showed high-frequency CT abnormalities (68.5%) regardless of the association with RA. Ground-glass opacity (56% vs. 24%), traction bronchiectasis (44% vs. 3%), architectural distortion (32% vs. 0%), centrilobular nodules (32% vs. 7%), and honeycombing (20% vs. 0%) were significantly more common in the PMR with RA group than in the PMR without RA group (P<.01). PMR patients with RA have more increased prevalence of chest CT abnormalities than those without RA.

Computed tomography of pulmonary changes in rheumatoid arthritis: carcinoembryonic antigen (CEA) as a marker of airway disease

Rheumatoid arthritis (RA) classically affects the joints, but can present extra-articular manifestations, including pulmonary disease. The present study aimed to identify possible risk factors or laboratory markers for lung involvement in RA, particularly the presence of rheumatoid factor (RF), anti-citrullinated peptide antibodies (ACPA), and tumor markers, by correlating them with changes observed on chest high-resolution computerized tomography (HRCT). This cross-sectional study involved RA patients who were examined and questioned by a specialist physician and later subjected to chest HRCT and blood collection for measurement of C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), rheumatoid factor (RF), ACPA (anti-vimentin and/or anti-CCP3), and the tumor markers carcinoembryonic antigen (CEA), CA 125, CA 15-3, and CA 19-9. A total of 96 patients underwent chest HRCT. The most frequent findings were bronchial thickening (27/28.1 %) and bronchiectasis (25/26 %). RF was present in 63.2 % of patients (55/87), and ACPA (anti-vimentin or anti-CCP3) was present in 72.7 % of patients (64/88). CEA levels were high in 14 non-smokers (37.8 %) and 23 smokers (62.2 %). CA-19-9 levels were high in 6 of 86 patients (7.0 %), CA 15-3 levels were high in 3 of 85 patients (3.5 %), and CA 125 levels were high in 4 of 75 patients (5.3 %). Multivariate analysis indicated a statistically significant association between high CEA levels and the presence of airway changes in patients with RA (p = 0.048). CEA can serve as a predictor of lung disease in RA and can help identify individuals who require more detailed examination for the presence of respiratory disorders.

Preclinical lung disease in early rheumatoid arthritis

Early detection and treatment of lung disease in patients with rheumatoid arthritis (RA) may ameliorate disease progression. The objectives of this study were to investigate the frequency of asymptomatic lung abnormalities in early RA patients and the potential association of positive RA blood reactive biomolecules with lung involvement. A prospective observational study was performed in a cohort of patients with early RA (joint symptoms < 2 years) without respiratory symptoms, who were included in a screening program for lung disease with a baseline chest radiograph (CR) and complete pulmonary function tests (PFTs). In those patients with lung abnormalities on the CR or PFTs, a high-resolution chest computed tomography scan (HRCT) was performed. We included 40 patients (30 women). Altered PFTs were detected in 18 (45%) of these patients. These cases had a diffusion lung transfer capacity of carbon monoxide (DLCO) of <80% of predicted, without a significant reduction in the forced vital capacity. The HRCT detected abnormalities in 11 of the 18 patients. Diffuse bronchiectasis was the main finding. An inverse correlation between the anti-citrullinated peptide antibody (ACPA) levels and DLCO was found. Asymptomatic lung disease is present in up to 45% of early RA patients and can be determined by PFTs and ACPA levels.

Imaging of pulmonary involvement in rheumatic disease

Lung disease commonly occurs in connective tissue diseases (CTD) and is an important cause of morbidity and mortality. Imaging is central to the evaluation of CTD-associated pulmonary complications. In this article, a general discussion of radiologic considerations is followed by a description of the pulmonary appearances in individual CTDs, and the imaging appearances of acute and nonacute pulmonary complications. The contribution of imaging to monitoring disease, evaluating treatment response, and prognostication is reviewed. Finally, we address the role of imaging in the challenging multidisciplinary evaluation of interstitial lung disease where there is an underlying suspicion of an undiagnosed CTD.

Diagnostic performance of measuring antibodies to the glycopeptidolipid core antigen specific to Mycobacterium avium complex in patients with rheumatoid arthritis: results from a cross-sectional observational study

Introduction

The aim of this study was to investigate the diagnostic performance of measuring antibodies to the glycopeptidolipid (GPL) core antigen specific to Mycobacterium avium complex (MAC) in patients with rheumatoid arthritis (RA).

Methods

We cross-sectionally investigated anti-GPL antibodies and radiographs of 396 patients with RA. A diagnosis of MAC pulmonary disease (MAC-PD) was made according to the criteria by the American Thoracic Society and the Infectious Diseases Society of America. Serum immunoglobulin A antibodies to MAC-specific GPL core antigen were measured by an enzyme immunoassay. All patients with RA with abnormal shadows on chest x-rays underwent chest computed tomography (CT). Bronchoscopy was performed on patients with negative cultures for MAC by expectorated sputum and positive CT findings compatible with MAC-PD.

Results

Ten patients were newly diagnosed with MAC-PD. Eight individuals who already had diagnoses of MAC-PD at the time of enrollment and nineteen who had negative expectorated sputum cultures for MAC and positive CT images compatible with MAC-PD and who refused bronchoscopy were excluded from the following analysis. Anti-GPL antibodies were detected in 12 of 369 patients. Eight of the ten patients with MAC-PD and 4 of 359 patients without MAC-PD tested positive for the anti-GPL antibodies. The specificity and sensitivity were 99 % and 80 %, respectively. Positive and negative predictive values were 67 %, and 97 %, respectively. When we analyzed diagnostic performance of the antibodies in 57 patients with RA who had abnormal shadows on chest x-rays, the positive and negative predictive values were 100 %, and 96 %, respectively. Twelve patients underwent bronchoscopy. Bronchoalveolar lavage fluid (BALF) samples from six patients were positive for MAC, and BALF samples from the remainder were negative. Anti-GPL antibodies were detected in the sera of all six patients with positive results for MAC by BALF sampling, whereas the antibodies were not detected in the sera from the remainder with negative results for MAC by BALF sampling.

Conclusions

The measurement of anti-GPL antibodies is useful as a supplementary diagnostic tool for MAC-PD in patients with RA and may provide a new strategy, in combination with chest x-ray and CT, for differentiating MAC-PD from other pulmonary comorbidities in patients with RA.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0787-y) contains supplementary material, which is available to authorized users.

An interesting finding of multiple calcified pulmonary nodules in a patient with rheumatoid arthritis

Calcified pulmonary (lung parenchymal) densities can occur in a number of conditions. A patient with rheumatoid arthritis presented with new right lung base nodules and left long base soft-tissue densities on his chest X-ray. These findings did not exist on his chest X-ray performed 2 years earlier. A subsequent thoracic CT scan showed multiple pleural-based irregular nodules of soft-tissue density that were partially calcified. There was also mediastinal and hilar lymphadenopathy. Following a discussion at the respiratory multidisciplinary team meeting, a CT-guided nodal biopsy was performed that showed necrotic lung tissue with palisaded histiocytes and fibrosis with chronic inflammation. No vasculitis or granulomata were seen and no there was evidence of malignancy. Appearances were consistent with a rheumatoid nodule. No mycobacteria or fungi were seen on Ziehl–Neelsen, Wade–Fite or periodic acid–Schiff stains. We concluded that this patient had unusual calcified rheumatoid lung nodules. Previously, calcified pulmonary nodules have been reported in the setting of Caplan’s syndrome in miners.

Biological agents and respiratory infections: Causative mechanisms and practice management

Biological agents are increasingly being used to treat patients with immune-mediated inflammatory disease. In Japan, currently approved biological agents for patients with rheumatoid arthritis (RA) include tumor necrosis factor inhibitors, interleukin-6 receptor-blocking monoclonal antibody, and T-cell costimulation inhibitor. Rheumatologists have recognized that safety issues are critical aspects of treatment decisions in RA. Therefore, a wealth of safety data has been gathered from a number of sources, including randomized clinical trials and postmarketing data from large national registries. These data revealed that the most serious adverse events from these drugs are respiratory infections, especially pneumonia, tuberculosis, nontuberculous mycobacteriosis, and Pneumocystis jirovecii pneumonia, and that the most common risk factors associated with these respiratory infections are older age, concomitant corticosteroid use, and underlying respiratory comorbidities. Because of this background, in 2014, the Japanese Respiratory Society published their consensus statement of biological agents and respiratory disorders. This review summarizes this statement and adds recent evidence, especially concerning respiratory infections in RA patients, biological agents and respiratory infections, and practice management of respiratory infections in patients treated with biological agents. To decrease the incidence of infections and reduce mortality, we should know the epidemiology, risk factors, management, and methods of prevention of respiratory infections in patients receiving biological agents.

Increased disease activity, severity and autoantibody positivity in rheumatoid arthritis patients with co-existent bronchiectasis

AIM

Patients with rheumatoid arthritis (RA) and co-existent bronchiectasis (BRRA) have a five-fold increased mortality compared to rheumatoid arthritis alone. Yet previous studies have found no difference in clinical and serological markers of RA disease severity between BRRA patients and RA alone. However, RA disease activity measures such as Disease Activity Score of 28 joints - C-reactive protein (DAS28-CRP) and anti-cyclic citrullinated peptide antibodies (anti-CCP) have not been studied, so we assessed these parameters in patients with BRRA and RA alone.

METHODS

BRRA patients (n = 53) had high-resolution computed tomography proven bronchiectasis without any interstitial lung disease and ≥ 2 respiratory infections/year. RA alone patients (n = 50) had no clinical or radiological evidence of lung disease. DAS28-CRP, rheumatoid factor (immunoglobulin M) and anti-CCP were measured in all patients, together with detailed clinical and radiology records.

RESULTS

In BRRA, bronchiectasis predated RA in 58% of patients. BRRA patients had higher DAS28 scores (3.51 vs. 2.59), higher levels of anti-CCP (89% vs. 46%) and rheumatoid factor (79% vs. 52%) (P = 0.003) compared to RA alone. Where hand and foot radiology findings were recorded, 29/37 BRRA (78%) and 13/30 (43%) RA alone had evidence of erosive change (P = 0.003). There were no significant differences between groups in smoking history or disease-modifying anti-rheumatic drug/biologic therapy.

CONCLUSIONS

Increased levels of RA disease activity, severity and RA autoantibodies are demonstrated in patients with RA and co-existent bronchiectasis compared to patients with RA alone, despite lower tobacco exposure. This study demonstrates that BRRA is a more severe systemic disease than RA alone.

Ultrasound in Rheumatologic Interstitial Lung Disease: A Case Report of Nonspecific Interstitial Pneumonia in Rheumatoid Arthritis

According to the American Thoracic Society (ATS)/European Respiratory Society consensus classification, idiopathic interstitial pneumonias (IIPs) include several clinic-radiologic-pathologic entities: idiopathic pulmonary fibrosis (IPF), usual interstitial pneumonia (UIP), nonspecific interstitial pneumonia (NSIP), cryptogenic organizing pneumonia, acute interstitial pneumonia, respiratory bronchiolitis-associated ILD, desquamative interstitial pneumonia, and lymphoid interstitial pneumonia. Ultrasound Lung Comets (ULCs) are an echographic chest-sonography hallmark of pulmonary interstitial fibrosis. We describe the ultrasound (US) findings in the follow-up of a NSIP's case in rheumatoid arthritis (RA).

Consolidation with a twisted appearance along the airways: a report of five cases of interstitial pneumonia

High-resolution CT showed areas of airspace consolidation with a twisted appearance of the airways, along with areas of peribronchial ground-glass attenuation and traction bronchiectasis, in five patients with interstitial pneumonia. These areas of airspace consolidation were termed "twisted consolidation" (TwC). The five patients included two patients receiving treatment for rheumatoid arthritis (RA), one patient with newly diagnosed RA, and one patient who subsequently showed RA. Three patients showed improvement after steroid administration. An association of TwC with RA is suspected, but further studies are necessary.

Lung involvement in connective tissue diseases: a comprehensive review and a focus on rheumatoid arthritis

The lungs are frequently involved in Connective Tissue Diseases (CTDs). Interstitial lung disease (ILD) is one of the most common pleuropulmonary manifestations that affects prognosis significantly. In practice, rheumatologists and other physicians tend to underestimate the impact of CTD-ILDs and diagnose respiratory impairment when it has reached an irreversible fibrotic stage. Early investigation, through clinical evidence, imaging and - in certain cases - lung biopsy, is therefore warranted in order to detect a possible ILD at a reversible initial inflammatory stage. In this review, we focus on lung injury during CTDs, with particular attention to ILDs, and examine their prevalence, clinical manifestations and histological patterns, as well as therapeutic approaches and known complications till date. Although several therapeutic agents have been approved, the best treatment is still not certain and additional trials are required, which demand more knowledge of pulmonary involvement in CTDs. Our central aim is therefore to document the impact that lung damage has on CTDs. We will mainly focus on Rheumatoid Arthritis (RA), which - unlike other rheumatic disorders - resembles Idiopathic Pulmonary Fibrosis (IPF) in numerous aspects.

Pleuropulmonary pathology in patients with rheumatic disease

Thoracic manifestations of rheumatic disease (RD) are increasingly recognized as a significant cause of morbidity and mortality worldwide. Rheumatologic underpinnings have been identified in a significant proportion of patients with interstitial lung disease. The 5 RDs most frequently associated with pleuropulmonary disease are (1) rheumatoid arthritis, (2) systemic lupus erythematosus, (3) progressive systemic sclerosis, (4) polymyositis/dermatomyositis, and (5) Sjögren syndrome. The onset of thoracic involvement in these diseases is variable. In some patients, it precedes the systemic disease or is its only manifestation. Moreover, there is a wide spectrum of clinical presentation ranging from subclinical abnormalities to acute respiratory failure. Histopathologically, the hallmark features of thoracic involvement by RD are inflammatory, targeting one or more lung compartments. The reactions range from acute to chronic, with remodeling by fibrosis being a common result. Although the inflammatory findings are often nonspecific, certain reactions or anatomic distributions may favor one RD over another, and occasionally, a distinctive histopathology may be present (eg, rheumatoid nodules). Three diagnostic dilemmas are encountered in patients with RD who develop diffuse lung disease: 1) opportunistic infection in the immunocompromised host, 2) drug toxicity related to the medications used to treat the systemic disease, and 3) manifestations of the patient's known systemic disease in lung and pleura. To confidently address the latter, the 5 major RDs are presented here, with their most common pleuropulmonary pathologic manifestations, accompanied by brief clinical and radiologic correlations.

Thoracic complications of rheumatoid disease

Rheumatoid arthritis is a relatively common multisystem disease associated with significant mortality and morbidity. Thoracic disease, both pleural and pulmonary, is a frequent extra-articular manifestation of rheumatoid arthritis and responsible for approximately 20% of rheumatoid-associated mortality. Rheumatoid disease and its associated therapies can affect all compartments of the lung inciting a range of stereotyped pathological responses and it is not infrequent for multiple disease entities to co-exist. In some instances, development of pulmonary complications may precede typical rheumatological presentation of the disease and be the first indication of an underlying connective tissue disease. The spectrum of thoracic disease related to rheumatoid arthritis is reviewed.

[Lung disease associated with connective tissue disease]

Connective tissue diseases are often associated with lung diseases that lead to high morbidity and mortality, including interstitial disease, airway disease, pleural lesions, and vascular disease. High resolution CT has high sensitivity for detecting parenchymal disease and potentially reversible lesions, helping to guide treatment. This article emphasizes interstitial pneumonia in association with connective tissue disease and the characteristics that differentiate this entity from idiopathic types. Likewise, we review the most common pulmonary manifestations of each connective tissue disease with the aim of providing the radiologist with a practical approach to the diagnosis and management of these diseases in daily clinical practice.

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.

[Intrathoracic lymphadenopathy: an unusual manifestation of rheumatoid arthritis]

Lung disease is the most frequent extra-articular manifestation of rheumatoid arthritis. It is detected in nearly 50% of patients with this multisystem affection, his knowledge has benefited from advances in computed tomography (CT). The inflammation can affect the pleura, the airways and the lung parenchyma. Intrathoracic lymphadenopathy complicating rheumatoid lung are not usual, and then pose the problem of differential diagnosis. We report a 51-year-old man, with a history of tobacco intoxication, suffering from rheumatoid arthritis who developed an interstitial lung disease at stage of fibrosis with mediastinal and hilar adenopathy. We will discuss the clinical, paraclinical, evolutionary and therapeutic particularities case.

Risk of infections in bronchiectasis during disease-modifying treatment and biologics for rheumatic diseases

Background

Bronchiectasis is frequently associated (up to 30%) with chronic inflammatory rheumatic diseases and leads to lower respiratory tract infections. Data are lacking on the risk of lower respiratory tract infections in patients treated with biologic agents.

Methods

Monocenter, retrospective systematic study of all patients with a chronic inflammatory rheumatic disease and concomitant bronchiectasis, seen between 2000 and 2009. Univariate and multivariate analyses were performed to evidence predictive factors of the number of infectious respiratory events.

Results

47 patients were included (mean age 64.1 ± 9.1 years, 33 (70.2%) women), with a mean follow-up per patient of 4.3 ± 3.1 years. Rheumatoid arthritis was the main rheumatic disease (90.1%). The mean number of infectious events was 0.8 ± 1.0 event per patient-year. The factors predicting infections were the type of treatment (biologic vs. non biologic disease-modifying treatments), with an odds ratio of 8.7 (95% confidence interval: 1.7-43.4) and sputum colonization by any bacteria (odds ratio 7.4, 2.0-26.8). In multivariate analysis, both factors were independently predictive of infections.

Conclusion

Lower respiratory tract infectious events are frequent among patients receiving biologics for chronic inflammatory rheumatic disease associated with bronchiectasis. Biologic treatment and pre-existing sputum colonization are independent risk factors of infection occurrence.

Pulmonary manifestations of rheumatoid arthritis

Pulmonary disease is a major source of morbidity and mortality in rheumatoid arthritis, manifesting most commonly as interstitial lung disease, airways disease, rheumatoid nodules, and pleural effusions. The diagnostic assessment of respiratory abnormalities is complicated by underlying risk for infection, the use of drugs with known pulmonary toxicity, and the frequency of lung disease related to rheumatoid arthritis itself. Evaluation and management of rheumatoid arthritis-associated pulmonary disease frequently necessitates a multidisciplinary approach.

Small airway obstruction in patients with rheumatoid arthritis

This work was intended to evaluate the prevalence of obstructive small-airway disease in patients with rheumatoid arthritis (RA) and its association with clinical characteristics. Pulmonary function testing (PFT) and high-resolution computed tomography (HRCT) were performed on 189 consecutive RA patients. Each case was diagnosed based on abnormal HRCT findings. We defined obstructive dysfunction of small airways as a forced expiratory flow from 25% to 75% of vital capacity (FEF(25-75)) value >1.96 residual standard deviation (RSD) below predicted values. We found 19 patients (10.1%) with an interstitial pneumonia (IP) pattern and 15 (7.9%) with a bronchiolitis pattern; the other 155 (82.0%) had no abnormal HRCT patterns. In patients with neither abnormal pattern, median values of percentage predicted for carbon monoxide diffusing capacity (DL(CO)) and ratio of DL(CO) to alveolar ventilation (DLco/VA) were within the normal range, but median FEF(25-75), forced expiratory flow at 25% of vital capacity (V(25)), and V(25)/height were <70% of predicted values. Forty-seven patients (30.3%) in this group had obstructive small-airway dysfunction. Multivariate logistic regression analysis indicated that this type of abnormality is strongly associated with respiratory symptoms [odds ratio (OR) 5.18; 95% confidence interval (CI) 1.70-15.75; p = 0.012), smoking history (OR 2.78; 95% CI 1.10-6.99; p = 0.03), and disease duration >10 years (OR 2.86; 95% CI 1.27-6.48; p = 0.012). Parenchymal micronodules, bronchial-wall thickening, and bronchial dilatation on HRCT scans were also predictive factors for abnormal FEF(25-75), although these morphological changes were too limited for us to diagnose these patients with the bronchiolitis pattern. Obstructive dysfunction of small airways is apparently common among RA patients, even among those with neither the IP nor the bronchiolitis pattern on HRCT scans. Factors significantly associated with abnormal FEF(25-75) are respiratory symptoms, smoking history, and RA duration.

The lung in rheumatoid arthritis

Rheumatoid arthritis (RA) is a common inflammatory disease, affecting about 1% of the population. Although a major portion of the disease burden including excess mortality is due to its extra-articular manifestations, the prevalence of RA-associated lung disease is increasing. RA can affect the lung parenchyma, airways, and the pleura; and pulmonary complications are directly responsible for 10 to 20% of all mortality. Even though pulmonary infection and drug toxicity are frequent complications of RA, lung disease directly associated with the underlying RA is more common. The prevalence of a particular complication varies based on the characteristics of the population studied, the definition of lung disease used, and the sensitivity of the clinical investigations employed. An overview of lung disease associated with RA is presented here with an emphasis on parenchymal lung disease, pleural effusion, and airway involvement.

Therapeutic options for systemic sclerosis related interstitial lung diseases

Interstitial lung disease (ILD) is a common manifestation of systemic sclerosis (SSc) mainly encountered in patients with diffuse disease. Unlike idiopathic interstitial pneumonias (IIP), SSc associated ILD corresponds to non-specific interstitial pneumonia (NSIP) in most cases, whereas usual interstitial pneumonia (UIP) is encountered less frequently. This explains the better prognosis of SSc associated ILD compared to IIP. However, severe restrictive lung disease represents one of the two main causes of disease-related death in SSc patients. The treatment of SSc associated ILD is not very well established. Anti-fibrosing treatments have failed to demonstrate any benefit and cyclophosphamide, which has been used in the treatment of this condition for about 15 years, has recently been evaluated in two prospective randomised studies which showed a significant but modest effect on respiratory function. Since none of the patients included in retrospective or prospective studies were selected on the basis of progression of ILD, and since only a minority of SSc patients develop severe ILD, further studies should focus on the subgroup of SSc patients with worsening ILD. A subgroup of patients with rapidly progressive ILD might benefit from pulsed intravenous cyclophosphamide combined with prednisone 15 mg daily but this remains to be confirmed.

Serodiagnosis of Mycobacterium avium-complex pulmonary disease with an enzyme immunoassay kit that detects anti-glycopeptidolipid core antigen IgA antibodies in patients with rheumatoid arthritis

Rheumatoid arthritis (RA) has many pulmonary manifestations, including bronchial abnormalities that can develop into Mycobacterium avium-complex (MAC) pulmonary disease (PD). MAC-PD can be lethal in patients receiving tumor necrosis factor-alpha blockers despite administration of antibiotics. Diagnosis of MAC-PD is often difficult, because MAC is an environmental organism. In this study, we investigated the usefulness of serodiagnosis of MAC-PD in RA patients by using an enzyme immunoassay (EIA) kit that detects anti-glycopeptidolipid (GPL) core antigen IgA antibodies. Antibody levels were measured in 63 patients with RA: 14 with MAC-PD plus 3 cultured nontuberculous mycobacteria (NTM) other than MAC, 16 with pulmonary abnormalities characterizing NTM but undetected in sputum culture, and 30 control subjects. RA patients with MAC-PD showed significantly higher antibody levels than controls (p = 0.02). The cutoff point was set at 0.7 IU/l, making the sensitivity and specificity of the antibody in MAC-PD and control patients 43% and 100%, respectively. The EIA kit is useful for diagnosis of MAC-PD in RA patients because of its high specificity. This test is an easier and less invasive form of examination and could therefore replace bronchoscopy as the main diagnostic procedure for RA patients with MAC-PD.