Contribution of pulmonary function tests (PFTs) to the diagnosis and follow up of connective tissue diseases

Spirometry Reference Equations Including Existing and Novel Parameters

Introduction

Spirometry is an essential component of pulmonary function testing, with interpretation dependent upon comparing results to normal. Reference equations for mean and lower limit of normal (LLN) are available for usual parameters, including forced vital capacity (FVC), forced expiratory volume in the first second of an FVC maneuver (FEV1), and FEV1/FVC. However, standard parameters do not fully characterize the flow-volume loop and equations are unavailable for the upper limit of normal (ULN). The aim of this study was to develop reference equations for existing and novel spirometry parameters, which more fully describe the flow-volume loop, and to compare these to previously reported equations.

Methods

Data from healthy participants in NHANES III was used to derive reference equations for existing and novel spirometry parameters accounting for birth sex, age, height, and ethnicity (Caucasian, Mexican American, Black) for ages 8 to 90 years. An iterative process determined %predicted LLN and ULN. Equations were compared to published reported equations.

Results

Reference equations were developed for mean, LLN and ULN for existing and novel spirometry parameters for ages 8 to 90. The derived equations closely match mean values of previously published equations, but more closely fit the LLN. Mexican-American and Caucasian values were similar (within 2%) so they were combined, while Black relative to Caucasian/Mexican-American values were lower for some parameters.

Conclusion

These reference equations, which account for birth sex, age, height, and ethnicity for existing and novel spirometry parameters, provide a more comprehensive and quantitative evaluation of spirometry and the flow-volume curve.

Characteristics of Chest HRCT and pulmonary function tests in elderly-onset primary Sjögren syndrome with interstitial lung disease

To investigate the characteristics of elderly-onset primary Sjögren syndrome (pSS) using chest high-resolution computed tomography and pulmonary function tests (PFTs). The data of 102 patients with pSS with interstitial lung disease were retrospectively analyzed. The chest high-resolution computed tomography, PFTs, and clinical and laboratory data were evaluated based on the age of onset: elderly-onset pSS (EopSS) (≥65 years) versus adult-onset pSS (AopSS) (<65 years). Among the 102 patients with pSS-interstitial lung disease, there were 34 of EopSS and 68 of AopSS. EopSS patients presented a significantly higher incidence of usual interstitial pneumonia (EopSS [38.2%] vs AopSS [11.8%], P = .005) and a significantly lower incidence of nonspecific interstitial pneumonia (EopSS [8.8%] vs AopSS [25%], P = .042). Unlike the AopSS group, the significant decreases in the vital capacity (VC) (the percentage of the predicted value of each parameter [%pred]) and the forced VC (%pred), PFTs showed that VC (%pred) and forced VC (%pred) were >80% in the EopSS group. Forced expiratory volume in 1 second significantly decreased and residual volume significantly increased in the EopSS group (P = .001). The percentage of small airway disease was significantly higher in the EopSS group (P = .021). Diffusing capacity of the lung for carbon monoxide/alveolar volume (%pred) was <80% in both groups with a lower percentage in the AopSS group. Usual interstitial pneumonia is more common in the EopSS group. Although there is no significant difference in ventilation dysfunction between the EopSS and AopSS groups, small airway disease is more common in the EopSS group, while restrictive ventilatory dysfunction is more common in the AopSS group. Therefore, the EopSS group has its own characteristics and it is worth studying and noting.

Clinical and Radiological Features of Interstitial Lung Diseases Associated with Polymyositis and Dermatomyositis

Polymyositis and dermatomyositis are autoimmune idiopathic systemic inflammatory diseases, characterized by various degrees of muscle inflammation and typical cutaneous lesions-the latter found in dermatomyositis. The underlying pathogenesis is characterized by a high level of uncertainty, and recent studies suggest diseases may have different immunopathological mechanisms. In polymyositis, components of the cellular immune system are involved, whereas in dermatomyositis, the pathogenesis is mainly mediated by the humoral immune response. The interstitial lung disease occurs in one-third of polymyositis and dermatomyositis patients associated with worse outcomes, showing an estimated excess mortality rate of around 40%. Lung involvement may also appear, such as a complication of muscle weakness, mainly represented by aspiration pneumonia or respiratory insufficiency. The clinical picture is characterized, in most cases, by progressive dyspnea and non-productive cough. In some cases, hemoptysis and chest pain are found. Onset can be acute, sub-acute, or chronic. Pulmonary involvement could be assessed by High Resolution Computed Tomography (HRCT), which may identify early manifestations of diseases. Moreover, Computed Tomography (CT) appearances can be highly variable depending on the positivity of myositis-specific autoantibodies. The most common pathological patterns include fibrotic and cellular nonspecific interstitial pneumonia or organizing pneumonia; major findings observed on HRCT images are represented by consolidations, ground-glass opacities, and reticulations. Other findings include honeycombing, subpleural bands, and traction bronchiectasis. In patients having Anti-ARS Abs, HRCT features may develop with consolidations, ground glass opacities (GGOs), and reticular opacities in the peripheral portions; nonspecific interstitial pneumonia or nonspecific interstitial pneumonia mixed with organizing pneumonia have been reported as the most frequently encountered patterns. In patients with anti-MDA5 Abs, mixed or unclassifiable patterns are frequently observed at imaging. HRCT is a sensitive method that allows one not only to identify disease, but also to monitor the effectiveness of treatment and detect disease progression and/or complications; however, radiological findings are not specific. Therefore, aim of this pictorial essay is to describe clinical and radiological features of interstitial lung diseases associated with polymyositis and dermatomyositis, emphasizing the concept that gold standard for diagnosis and classification-should be based on a multidisciplinary approach.

Systemic Lupus Erythematosus and Lung Involvement: A Comprehensive Review

Systemic lupus erythematosus (SLE) is a complex autoimmune disease with multiorgan manifestations, including pleuropulmonary involvement (20-90%). The precise mechanism of pleuropulmonary involvement in SLE is not well-understood; however, systemic type 1 interferons, circulating immune complexes, and neutrophils seem to play essential roles. There are eight types of pleuropulmonary involvement: lupus pleuritis, pleural effusion, acute lupus pneumonitis, shrinking lung syndrome, interstitial lung disease, diffuse alveolar hemorrhage (DAH), pulmonary arterial hypertension, and pulmonary embolism. DAH has a high mortality rate (68-75%). The diagnostic tools for pleuropulmonary involvement in SLE include chest X-ray (CXR), computed tomography (CT), pulmonary function tests (PFT), bronchoalveolar lavage, biopsy, technetium-99m hexamethylprophylene amine oxime perfusion scan, and (18)F-fluorodeoxyglucose positron emission tomography. An approach for detecting pleuropulmonary involvement in SLE includes high-resolution CT, CXR, and PFT. Little is known about specific therapies for pleuropulmonary involvement in SLE. However, immunosuppressive therapies such as corticosteroids and cyclophosphamide are generally used. Rituximab has also been successfully used in three of the eight pleuropulmonary involvement forms: lupus pleuritis, acute lupus pneumonitis, and shrinking lung syndrome. Pleuropulmonary manifestations are part of the clinical criteria for SLE diagnosis. However, no review article has focused on the involvement of pleuropulmonary disease in SLE. Therefore, this article summarizes the literature on the epidemiology, pathogenesis, diagnosis, and management of pleuropulmonary involvement in SLE.

Evaluation of Interstitial Lung Disease in Idiopathic Inflammatory Myopathies Through Semiquantitative and Quantitative Analysis of Lung Computed Tomography

PURPOSE

To perform a semiquantitative and quantitative analysis of interstitial lung disease (ILD), through computed tomography (CT), in different serological subgroups of idiopathic inflammatory myopathies (IIM) patients, to find radiologic and clinical differences of disease related to serology.

MATERIALS AND METHODS

This was a prospective study, which included 98 IIM patients, divided into serological subgroups: anti-aminoacyl-transfer-RNA-synthetases (anti-ARS) positive and myositis-specific autoantibodies (MSA) negative.For each baseline CT the total semiquantitative score of Warrick (WS) and the automated software (Computer-Aided Lung Informatics for Pathology Evaluation and Rating) quantitative scores interstitial lung disease % (ILD%) and vascular-related structure % (VRS%) were calculated. Pulmonary function tests included total lung capacity % (TLC%), forced vital capacity % (FVC%), and diffusing capacity of the lung for carbon monoxide % (DLCO%).

RESULTS

Inverse correlations ( P <0.001) between the radiologic scores and the functional scores DLCO% and TLC% were found, the most relevant being between ILD% and DLCO% (ρ=-0.590), VRS% and DLCO% (ρ=-0.549), and WS and DLCO% (ρ=-0.471).Positive correlations between ILD% and VRS% (ρ=0.916; P <0.001), WS and ILD% (ρ=0.663; ρ<0.001), and WS and VRS% (ρ=0.637; P <0.001) were obtained.Statistically significant higher values of WS, ILD%, and VRS% were found in the anti-ARS group (WS=15; ILD%=11; VRS%=3.5) compared with the MSA negative one (WS=2.5; ILD%=0.84; VRS%=2.2).The nonspecific interstitial pneumonia pattern was dominant. No statistically significant differences emerged at pulmonary function tests.

CONCLUSIONS

In this study, ILD in anti-ARS-positive and MSA-negative groups was defined through semiquantitative and quantitative analysis of lung CT. The inverse correlations between the radiologic scores and TLC% and DLCO% ( P <0.001) confirm the role of lung CT in the evaluation of ILD in IIM.

Lung involvement in children with newly diagnosed rheumatic diseases: characteristics and associations

BACKGROUND

Pulmonary complications of rheumatic diseases may cause functional impairment and increase mortality. However, reports regarding detection of lung involvement in children with treatment-naive, newly diagnosed rheumatic diseases are scarce. Herein, we aimed to describe the characteristics of such patients and explore the association between lung involvement and rheumatic disease.

METHODS

From January 2019 to June 2021, 48 pediatric patients with treatment-naive, newly diagnosed rheumatic diseases at Department of Rheumatology and Immunology, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University were included with pulmonary function tests (PFTs) and high-resolution computed tomography (HRCT) findings, and 51 age-matched healthy controls were examined based on PFTs. Univariate and multivariable logistic regression analyses were used to investigate the clinical characters and laboratory parameters associated with lung involvement in these patients.

RESULTS

Asymptomatic patients had a faster respiratory rate and a higher ratio of forced expiratory volume in 1 s/forced vital capacity than the controls (P < 0.05). More patients than controls were observed to have a decreased DL_CO below the lower limit of normal (18 of 45 [40.0%] vs. 6 of 36, respectively; P = 0.041). Among the 48 patients, 8 (16.7%) had abnormal HRCT findings and 27 (56.3%) had abnormal PFT results. Thirty-one (64.6%) patients had lung involvement. Logistic regression revealed that increases in the erythrocyte sedimentation rate (ESR) and CD4/CD8 ratio were associated with increased odds ratio of lung involvement (1.037, 95% CI: 1.003-1.072; 9.875, 95% CI: 1.296-75.243, respectively).

CONCLUSIONS

Pediatric patients with treatment-naive, newly diagnosed rheumatic diseases are prone to pulmonary involvement. Increased ESR and CD4/CD8 are associated with elevated odds of lung involvement in patients. We recommend routine pulmonary evaluation in such patients, especially in high-risk patients, even in the absence of respiratory symptoms, once they are diagnosed with rheumatic disease.

Clinical and radiological features of lung disorders related to connective-tissue diseases: a pictorial essay

Connective tissue diseases (CTDs) include a spectrum of disorders that affect the connective tissue of the human body; they include autoimmune disorders characterized by immune-mediated chronic inflammation and the development of fibrosis. Lung involvement can be misdiagnosed, since pulmonary alterations preceded osteo-articular manifestations only in 20% of cases and they have no clear clinical findings in the early phases. All pulmonary structures may be interested: pulmonary interstitium, airways, pleura and respiratory muscles. Among these autoimmune disorders, rheumatoid arthritis (RA) is characterized by usual interstitial pneumonia (UIP), pulmonary nodules and airway disease with air-trapping, whereas non-specific interstitial pneumonia (NSIP), pulmonary hypertension and esophageal dilatation are frequently revealed in systemic sclerosis (SSc). NSIP and organizing pneumonia (OP) may be found in patients having polymyositis (PM) and dermatomyositis (DM); in some cases, perilobular consolidations and reverse halo-sign areas may be observed. Systemic lupus erythematosus (SLE) is characterized by serositis, acute lupus pneumonitis and alveolar hemorrhage. In the Sjögren syndrome (SS), the most frequent pattern encountered on HRCT images is represented by NSIP; UIP and lymphocytic interstitial pneumonia (LIP) are reported with a lower frequency. Finally, fibrotic NSIP may be the interstitial disease observed in patients having mixed connective tissue diseases (MCTD). This pictorial review therefore aims to provide clinical features and imaging findings associated with autoimmune CTDs, in order to help radiologists, pneumologists and rheumatologists in their diagnoses and management.

Clinical experience in anti-synthetase syndrome: a monocentric retrospective analytical study

OBJECTIVES: Anti-synthetase syndrome (ASS) is a rare autoimmune disorder combining autoantibodies and specific clinical manifestations. One of the particularities of ASS is the pleiomorphic radiological presentation seen at the initial work-up. Evaluating treatment response can also be challenging and requires specific clinical, functional, biological and radiological monitoring. For these reasons, it is fundamental to identify specific radiological and clinical features of ASS for improved diagnosis and therapeutic approaches.METHODS: We retrospectively studied all patients suffering from ASS in the CHU of Liège from 2008 to 2019. We analysed the clinical features, pulmonary function tests (PFTs), computed tomography (CT), and longitudinal evolution with regard to patient treatment.RESULTS: In the whole cohort of 30 patients, we identified 19 with anti-JO1 antibodies, 5 with anti-PL12 antibodies and 6 with anti-PL7 antibodies. The sex ratio was slightly in favour of males. Interestingly, PL-12 syndrome was more likely to be present in younger patients than those associated with other antibodies. Overall, 77% of the overall cohort exhibited specific pulmonary involvement without any significant difference with regard to the severity assessed by PFT at diagnosis. In contrast, the radiological presentation was pleomorphic for anti-JO1 syndrome, and anti-PL12 syndrome exhibited mainly ground-glass opacities (GGOs) and reticular abnormalities, while those with anti-PL7 antibodies showed reticulations and bronchiectasis. Longitudinal CT analysis mainly showed a reduction in consolidations and GGOs with specific therapies.CONCLUSION: In our single-centre retrospective study, we found different profiles for different autoantibodies according to age and radiological appearance.

Rheumatoid Arthritis and Associated Lung Diseases: A Comprehensive Review

Rheumatoid arthritis (RA) is a prevalent autoimmune disorder affecting 0.5-1% of the population in North America and Europe. Pulmonary manifestations in rheumatoid arthritis patients result in significant morbidity and mortality. Management of these pulmonary manifestations in RA patients causes various challenges for the physicians. This review article has discussed the current state of knowledge of these pulmonary manifestations, including interstitial lung diseases, airway-related diseases, pulmonary vasculature, and pleural involvement in RA patients. This review article has also explored various pharmacological options, including steroids, disease-modifying antirheumatic drugs (DMARDs), immunosuppressive drugs, and biologic agents. Non-pharmacological options include conservative treatment, supplemental oxygen, pulmonary rehabilitation, smoking cessation, and lung transplantation.

Education and Use of Lung Ultrasound in Rheumatology and Pneumology in Spain: A SER-SEPAR Survey

INTRODUCTION

Lung ultrasound (LUS) is a clinical and research tool with great potential in the diagnosis and monitoring of diffuse interstitial lung disease (ILD) present in systemic autoimmune diseases (SAD). Appropriate training in LUS is essential for the correct and safe use of this technique.

OBJECTIVE

To document the current state of LUS education and use among Spanish rheumatologists and pneumologists.

MATERIAL AND METHODS

A national online survey was designed for members of the Spanish Society of Rheumatology and the ILD Area of the Spanish Society of Pneumology and Thoracic Surgery. The survey consisted of 22 questions on demographics, professional activity, performance and training in LUS.

RESULTS

One hundred and thirty-five (56.72% rheumatologists, 41.79% pneumologists) responded to the survey. Of these, 56.30% were part of an ILD Unit in their centre. LUS in clinical practice was performed by 35.82% but only 14.93% performed it in ILD, mainly for diagnostic purposes. Training in LUS of responders had been diverse in format, content and sponsors. The vast majority (87.79%) considered that the optimal model of education in LUS should be standardized and structured and consist of a combination of theoretical-practical courses and the conduct of a minimum number of supervised LUS examinations, with competency assessment.

CONCLUSIONS

The current lack of formal structured education in LUS is an opportunity to develop quality educational programmes in this emerging field.

Manejo de las enfermedades pulmonares intersticiales difusas (EPID) asociadas a enfermedades autoinmunes, por el neumólogo en las diferentes unidades de EPID en España

Introduction

The aim of the study was to know the management of patients with diffuse interstitial lung disease (ILD) associated with a systemic autoimmune diseases (SAD) in pulmonology outpatient clinics in Spain.

Methodology

The ILD work area of the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR) designed a self-completed questionnaire of 25 questions, on aspects related to the diagnosis and treatment of ILD-SAD. This was distributed among the attendees of the winter meeting of the ILD Area and later via e-mail to all the members of the ILD area of SEPAR. Participation was anonymous, voluntary and without consideration.

Results

74 pulmonologists from 58 hospitals participated. 77% had a specialized ILD consultation. All Units with SEPAR accreditation had a committee made up of pulmonologists and radiologists and a majority participation of pathologists and rheumatologists. In 75% of the centers there was a close collaboration with Rheumatology for the management of ILD-SAD. 85% considered that the frequency of ILD-SAD consults is increasing, the most frequent being ILD associated with rheumatoid arthritis. The treatment of ILD-SAD is decided by consensus between pulmonologist and rheumatologist in 91.3% of the cases. 67% of pulmonologists consider that immunosuppressants and biological therapies can slow down the progression of ILD-SAD. 51% use antifibrotics therapies in these pathologies.

Conclusions

Almost all of the accredited Spanish ILD Units by SEPAR have established collaborations with Rheumatology for the adequate management of patients with ILD-SAD, this practice having been extended to units not yet accredited.

Predictors of Long-term Outcomes in Patients With Connective Tissue Disease Associated With Pulmonary Arterial Hypertension

BACKGROUND/OBJECTIVE

Pulmonary arterial hypertension (PAH) is a progressive disease characterized by increased pulmonary arterial pressure and pulmonary vascular resistance that can lead to right-sided heart failure. Connective tissue disease-associated PAH (CTD-PAH) often has poorer outcomes than idiopathic or hereditary PAH, suggesting the presence of non-PAH factors that could affect the prognoses. This cohort study aimed to identify prognostic factors for CTD-PAH management.

METHODS

Medical records from April 1999 to November 2014 were reviewed to determine the time from treatment initiation to the occurrence of a clinically worsening event and the time elapsed until death. Data at baseline and the final assessment were used to identify prognostic factors associated with events using univariate and multivariate analyses by the stepwise Cox regression method.

RESULTS

In 36 patients with CTD-PAH analyzed, the proportions with no clinically worsening events at 1, 2, and 3 years after treatment initiation were 62%, 52%, and 45%, respectively, with survival rates of 88%, 77%, and 77%, respectively. The regression model showed that reduced hemoglobin at baseline, reduced qR pattern in electrocardiogram lead V1, increased 60-minute erythrocyte sedimentation rate, and increased mean pulmonary arterial pressure at the final assessment were risk factors that were significantly associated with clinical worsening. For survival, no prognostic factor was identifiable.

CONCLUSIONS

Hemodynamic and non-PAH factors, such as anemia, nutritional status, and inflammatory activity of the underlying CTD, which are not listed in the risk assessment table of PAH guidelines, should be strictly controlled to improve the prognosis of patients with CTD-PAH. A more multifactorial treatment strategy should be developed.

Risk factors for progression of interstitial lung disease in Sjögren's syndrome: a single-centered, retrospective study

OBJECTIVE

To identify clinical characteristics and risk factors related to the progression of interstitial lung disease (ILD) in patients with primary Sjögren's syndrome (pSS).

METHODS

In this single-centered, retrospective study, a total of 83 identified pSS-ILD patients with relatively complete clinical data were finally enrolled. Clinical symptoms, laboratory data, high-resolution computed tomography (HRCT), and pulmonary function test (PFT) results were collected. A logistic regression analysis was performed to determine the independent risk factors for ILD progression, and a nomogram was plotted to construct a predictive model.

RESULTS

The prevalence of pSS-ILD in our study was 18.89%. Among the 83 enrolled patients, 32 (38.6%) underwent ILD progression. The characteristic features associated with the progression of ILD included male sex, non-sicca onset, reticular pattern on HRCT, higher levels of baseline lactic dehydrogenase (LDH), and low baseline forced vital capacity (FVC). The results of multivariate logistic regression indicated that LDH (OR 1.008, p = 0.030) was an independent risk factor for ILD progression, while sicca onset (OR 0.254, p = 0.044) and FVC (OR 0.952, p = 0.003) were protective factors for ILD progression. A simple predictive model for ILD progression in pSS was developed and validated.

CONCLUSION

pSS patients with non-sicca onset, high baseline LDH level, and low baseline FVC were at higher risk of ILD progression.

Dominating Cause of Pulmonary Hypertension May Change Over Time-Diagnostic and Therapeutic Considerations in a Patient with Pulmonary Hypertension Due to Rheumatoid Arthritis with Lung Involvement

Chronic lung diseases are one of the most frequent causes of pulmonary hypertension (PH). The diagnostic challenge is to differentiate PH due to chronic lung disease from pulmonary arterial hypertension (PAH) with coexisting chronic lung disease. Moreover, the dominating cause of PH may change over time, requiring the implementation of new diagnostic procedures and new treatment modalities. We present a 68-year-old female, initially diagnosed with PH in the course of interstitial lung disease, with restrictive impairment of lung function. Therapy with immunosuppressive drugs resulted in significant clinical, radiological and functional improvement. However, five years later, arthritis symptoms developed, with PH worsening, despite stable lung disease. The patient was diagnosed with PAH in the course of rheumatoid arthritis. The introduction of sildenafil resulted in marked clinical and hemodynamic responses. Long-term survival (eleven years from PH onset and five years from PAH confirmation) has been achieved, and the patient remains in good functional condition. As the differential diagnosis of PH in patients with lung diseases is complex, the cooperation of pulmonologists and cardiologists is mandatory to obtain therapeutic success.

Diagnosis and management of lung involvement in systemic lupus erythematosus and Sjögren's syndrome: a literature review

Lung involvement in systemic lupus erythematosus (SLE) and primary Sjögren's syndrome (pSS) has extensively been outlined with a multiplicity of different manifestations. In SLE, the most frequent finding is pleural effusion, while in pSS, airway disease and parenchymal disorders prevail. In both cases, there is an increased risk of pre-capillary and post-capillary pulmonary arterial hypertension (PAH) and pulmonary venous thromboembolism (VTE). The risk of VTE is in part due to an increased thrombophilic status secondary to systemic inflammation or to the well-established association with antiphospholipid antibody syndrome (APS). The lung can also be the site of an organ-specific complication due to the aberrant pathologic immune-hyperactivation as occurs in the development of lymphoma or amyloidosis in pSS. Respiratory infections are a major issue to be addressed when approaching the differential diagnosis, and their exclusion is required to safely start an immunosuppressive therapy. Treatment strategy is mainly based on glucocorticoids (GCs) and immunosuppressants, with a variable response according to the primary pathologic process. Anticoagulation is recommended in case of VTE and multi-targeted treatment regimens including different drugs are the mainstay for PAH management. Antibiotics and respiratory physiotherapy can be considered relevant complement therapeutic measures. In this article, we reviewed lung manifestations in SLE and pSS with the aim to provide a comprehensive overview of their diagnosis and management to physicians taking care of patients with connective tissue diseases.

Relationship between rheumatoid arthritis and pulmonary function measures on spirometry in the UK Biobank

OBJECTIVE

We investigated the independent relationship of rheumatoid arthritis (RA) with type and severity of pulmonary patterns on spirometry compared to general population controls.

METHODS

This cross-sectional study investigated the association of RA and pulmonary function measures on spirometry among subjects who had spirometry performed for research purposes in the UK Biobank. RA cases were identified by self-report and current DMARD/glucocorticoid use. General population controls denied RA. Outcomes included continuous % predicted forced expiratory volume in 1 second (FEV₁ ) and forced vital capacity (FVC), type of spirometric pattern (restrictive or obstructive), and severity. We used multivariable regression to estimate the effects of RA cases versus controls, adjusting for age, sex, body mass index (BMI), and smoking status/pack-years.

RESULTS

Among 350,776 analyzed subjects with spirometry performed (mean age 56.3 years, 55.8% female, and 45.5% ever smokers), we identified 2,008 cases of treated RA. In multivariable analyses, RA was associated with lower % predicted FEV₁ (β -2.93, 95%CI -3.63,-2.24), % predicted FVC (β -2.08, 95%CI -2.72,-1.45), and FEV₁ /FVC (β -0.008, 95%CI -0.010,-0.005) than controls. RA was associated with restrictive (OR 1.36, 95%CI 1.21,1.52) and obstructive (OR 1.21, 95%CI 1.07,1.37) patterns independent of confounders. RA had the strongest associations for severe restrictive and obstructive patterns.

CONCLUSION

RA was associated with increased odds of restrictive and obstructive patterns, and this relationship was not explained by confounders including smoking. In addition to restrictive lung disease, clinicians should also be aware that airflow obstruction may be a pulmonary manifestation of RA.

Rheumatoid arthritis related interstitial lung disease

INTRODUCTION

Interstitial lung disease (ILD) represents a frequent extra-articular manifestation of rheumatoid arthritis (RA) deeply impacting both quality of life and overall prognosis. Areas covered: A literature search was performed including PubMed, Embase, Scopus, and Web of Science. Many retrospective studies investigated the possible risk factors for RA-related ILD (RA-ILD), aiming to identify patients at risk. Among them, males, smokers, positivity of anti-citrullinated peptide antibodies have been associated with RA-ILD, such as some genetic haplotypes. Usual interstitial pneumonia is the histologic and radiologic pattern most frequently observed, followed by nonspecific interstitial pneumonia. Since lung involvement can represent the RA onset, an early differential diagnosis with idiopathic interstitial pneumonia can be difficult or sometimes impossible. High-resolution computed tomography represents the gold standard for ILD diagnosis, while multidisciplinary discussion should be required to assess disease staging, severity and progression.  Expert opinion: Management of RA-ILD patients is challenging due to the lack of evidence-based data regarding both assessment and treatment. Moreover, the high variability of clinical presentation and evolution makes it difficult to establish the correct therapeutic strategy. Currently, multidisciplinary approach, including at least rheumatologists, pulmonologists, and radiologists, is desirable to define therapy and follow-up strategies.

Chest wall muscle atrophy as a contributory factor for forced vital capacity decline in systemic sclerosis-associated interstitial lung disease

OBJECTIVE

To investigate the potential contribution of accessory respiratory muscle atrophy to the decline of forced vital capacity (FVC) in patients with SSc-associated interstitial lung disease (ILD).

METHODS

This single-centre, retrospective study enrolled 36 patients with SSc-ILD who underwent serial pulmonary function tests and chest high-resolution CT (HRCT) simultaneously at an interval of 1-3 years. The total extent of ILD and chest wall muscle area at the level of the ninth thoracic vertebra on CT images were evaluated by two independent evaluators blinded to the patient information. Changes in the FVC, ILD extent, and chest wall muscle area between the two measurements were assessed in terms of their correlations. Multiple regression analysis was conducted to identify the independent contributors to FVC decline.

RESULTS

Interval changes in FVC and total ILD extent were variable among patients, whereas chest wall muscle area decreased significantly with time (P=0.0008). The FVC change was negatively correlated with the change in ILD extent (r=-0.48, P=0.003) and was positively correlated with the change in the chest wall muscle area (r = 0.53, P=0.001). Multivariate analysis revealed that changes in total ILD extent and chest wall muscle area were independent contributors to FVC decline.

CONCLUSION

In patients with SSc-ILD, FVC decline is attributable not only to the progression of ILD but also to the atrophy of accessory respiratory muscles. Our findings call attention to the interpretation of FVC changes in patients with SSc-ILD.

Evaluation of rheumatoid arthritis and connective tissue disease-related interstitial lung disease with pulmonary physiologic test, HRCT, and patient-based measures of dyspnea and functional disability

OBJECTIVES

We aim to investigate the relationship between pulmonary function and imaging parameters with symptom-related patient-reported outcome measures (PROs).

METHOD

We included 65 patients of rheumatoid arthritis (RA) and connective tissue disease (CTD) with and without interstitial lung disease (ILD) into this cross-sectional study. We evaluated the relationship between FVC, DLco, and PROs and compared to HRCT findings. PROs included visual analogue scale for breathing, modified Borg scale, medical research council dyspnea scale, St. George's respiratory questionnaire (SGRQ), Leicester cough questionnaire, and Short Form 36 quality of life (SF-36 QoL).

RESULTS

The mean age was 57.4 ± 9.7 and 61.9% (39/65) of patients had an established ILD. In RA-ILD group, SGRQ score was higher (p < 0.001) and SF-36 physical functioning score was lower (p = 0.02) than CTD-ILD group. In RA group, there was a significant correlation between FVC and SF-36 role functioning/physical score (r = 0.724, p = 0.012). In CTD group, SF-36 general health score was correlated with both FVC (r = 0.441, p = 0.045) and DLco (r = 0.485, p = 0.035), and also SF-36 physical functioning score was correlated with FVC (r = 0.441, p = 0.040). PROs were found to be similar between ILD and non-ILD patients. SF-36 QoL total and SGRQ outcomes were worse in non-ILD group.

CONCLUSIONS

We concluded that PROs could be used to evaluate health-related quality of life (HRQoL) in RA- or CTD-related ILD. The physical health determinants of HRQoL are measurably worse in RA-ILD patients than in CTD patients. But, PROs may not be very helpful in differentiating patients with cough and/or shortness of breath due to ILD or non-ILD causes in RA/CTD.

KEY POINTS

• HRQoL may be affected differently among specific subtypes of ILD. • PROs can be used to evaluate dyspnea and function of patients with RA- or CTD-related ILD but are not distinguished from patients with cough and/or shortness of breath due to non-ILD causes in RA/CTD.

Predicted Reference Equations for Spirometry Indices as a Proxy from Anthropometry Measurements of Nigerian Children with Sickle Cell Anaemia Aged 5-12 Years

BACKGROUND

Significant morbidity and mortality in patients with sickle cell disease are accounted for by lung complications. To facilitate good respiratory care for children with sickle cell anaemia the generation of local predicted values is highly important.

OBJECTIVE

To determine the reference equations for spirometry indices estimation in children with sickle cell anaemia, which can be readily used as proxy when there is no easy accessibility to spirometer.

METHODS

A cross-sectional study with linear regression models developed to estimate reference values for spirometric indices in Nigerian children with sickle cell anaemia aged 5-12 years.

RESULTS

Age as independent variables for estimation of forced expiratory volume in 1 s (FEV1) was associated with lowest coefficient of determination (R2) and highest standard error. The coefficient of determination (R2) and standard error was highest and lowest, respectively, when arm span was used to determine peak expiratory flow rate (PEFR). Prediction models for PEFR and FEV1 gave the closest mean estimates that were 0.18 and 0.16 lower and higher than the actual mean PEFR and FEV1, respectively, but the differences was significant only in FEV1. On the contrary the prediction models for forced vital capacity (FVC) gave mean estimates that was 1.02 higher than the actual mean FVC, however, the finding was not significant.

CONCLUSION

Preferred proxy for spirometry indices in children with sickle cell anaemia may be arm span.

Education and Use of Lung Ultrasound in Rheumatology and Pneumology in Spain: A SER-SEPAR Survey

INTRODUCTION

Lung ultrasound (LUS) is a clinical and research tool with great potential in the diagnosis and monitoring of diffuse interstitial lung disease (ILD) present in systemic autoimmune diseases (SAD). Appropriate training in LUS is essential for the correct and safe use of this technique.

OBJECTIVE

To document the current state of LUS education and use among Spanish rheumatologists and pneumologists.

MATERIAL AND METHODS

A national online survey was designed for members of the Spanish Society of Rheumatology and the ILD Area of the Spanish Society of Pneumology and Thoracic Surgery. The survey consisted of 22 questions on demographics, professional activity, performance and training in LUS.

RESULTS

One hundred and thirty-five (56.72% rheumatologists, 41.79% pneumologists) responded to the survey. Of these, 56.30% were part of an ILD Unit in their centre. LUS in clinical practice was performed by 35.82% but only 14.93% performed it in ILD, mainly for diagnostic purposes. Training in LUS of responders had been diverse in format, content and sponsors. The vast majority (87.79%) considered that the optimal model of education in LUS should be standardized and structured and consist of a combination of theoretical-practical courses and the conduct of a minimum number of supervised LUS examinations, with competency assessment.

CONCLUSIONS

The current lack of formal structured education in LUS is an opportunity to develop quality educational programmes in this emerging field.

Serum Krebs von den Lungen-6 and lung ultrasound B lines as potential diagnostic and prognostic factors for rheumatoid arthritis-associated interstitial lung disease

INTRODUCTION

Rheumatoid arthritis (RA)-associated interstitial lung disease (ILD) (RA-ILD) is a serious systemic RA manifestation with high mortality that needs proper, accurate, and sensitive assessment tools.

OBJECTIVES

Firstly, evaluate serum Krebs von den Lungen-6 (KL-6) levels and lung ultrasound B lines (LUS B lines) score in RA-ILD correlating them with the severity of ILD assessed by high-resolution computed tomography (HRCT) and pulmonary function tests (PFTs). Secondly, determine cut-off values for LUS and KL-6 in RA-ILD assessment and outcome prediction.

METHODS

A case-control study included seventy-five RA-ILD patients with an equal number of matched RA patients without ILD. Clinical assessment includes DAS-28 and PFTs, laboratory assessment of serum KL-6 by latex-enhanced immunoturbidimetric assay, and radiological evaluation of ILD using semiquantitative CT grade and LUS B lines.

RESULTS

RA-ILD patients had significantly higher serum KL6 compared to those without ILD (1025.5 ± 419.6 vs. 237.5 ± 51.9, p ≤ 0.001). Serum KL6 was positively correlated with HRCT and LUS scores (r = 0.93, r = 0.97, respectively) with negative correlation with FVC% and FEV1% (r = - 0.93, r = - 0.91, respectively). LUS was positively correlated with KL6 and HRCT (r = 0.97, r = 0.944, respectively) while, negatively correlated with PFTs. Cut-off values of KL6 and LUS were 277.5 U/ml and < 5.5, with AUC 0.878 and 1, sensitivity 86.7% and 100%, and specificity 88% and 100%, respectively.

CONCLUSIONS

The non-invasive, radiation-free LUS with a score < 5.5 combined with serum KL6 could be helpful for RA-ILD assessment correlating with HRCT and disease severity. Serum KL6 combined with LUS is important new and potential prognostic factor predicting poor outcomes in RA-ILD. Further large-scale, multi-center, and prospective studies are needed to confirm these findings.

KEY POINTS

• Combination of the non-invasive, radiation-free LUS with a score < 5.5 and serum KL6 levels of 277.5 U/ml is recommended as prognostic tools for RA-ILD. • Easily obtainable tests such as serum KL-6, inflammatory markers, and LUS are sensitive for assessing RA-ILD and the risk of poor outcomes in patients with RA-ILD. • RA-ILD patients with higher KL6 levels, higher LUS scores had a poor prognosis with short survival. • LUS B lines could be used as the first imaging tool for the evaluation of RA-ILD decreasing the risk of HRCT radiation exposure in asymptomatic or mild RA-ILD patients.

Lung complications of Sjogren syndrome

Primary Sjogren syndrome (pSS) is a systemic autoimmune disease characterised by lymphocytic infiltration of exocrine glands and by a number of systemic manifestations, including those regarding the lung. Pulmonary involvement in pSS includes interstitial lung disease (ILD) and airway disease, together with lymphoproliferative disorders.

Patients with pSS-ILD report impaired health-related quality of life and a higher risk of death, suggesting the importance of early diagnosis and treatment of this type of pulmonary involvement. In contrast, airway disease usually has little effect on respiratory function and is rarely the cause of death in these patients.

More rare disorders can be also identified, such as pleural effusion, cysts or bullae.

Up to date, available data do not allow us to establish an evidence-based treatment strategy in pSS-ILD. No data are available regarding which patients should be treated, the timing to start therapy and better therapeutic options. The lack of knowledge about the natural history and prognosis of pSS-ILD is the main limitation to the development of clinical trials or shared recommendations on this topic. However, a recent trial showed the efficacy of the antifibrotic drug nintedanib in slowing progression of various ILDs, including those in pSS patients.

Primary Sjogren syndrome is a systemic autoimmune disease with a possible lung involvement, that it appears as polymorphic, including interstitial lung disease, airway disease and lymphoproliferative disorders with different degree of severityhttps://bit.ly/3akjk4b

Usefulness of digital velcro crackles detection in identification of interstitial lung disease in patients with connective tissue diseases

Objectives

This study aims to evaluate the diagnostic accuracy of the VECTOR software in patients with connective tissue diseases (CTDs), compared with the reference standard of high-resolution computed tomography (HRCT).

Patients and methods

The study included 98 consecutive patients of CTD (24 males, 74 females; median age 66 years; range, 24 to 85 years) with a recent HRCT. Patients were evaluated in a blindly manner by VECTOR and the results obtained by the algorithm were compared with the presence of interstitial lung disease (ILD) according to HRCT.

Results

Interstitial lung disease was detected in 42.8% of subjects. VECTOR correctly classified 81/98 patients, with a diagnostic accuracy of 82.6%; sensitivity and specificity were 88.1% and 78.6%, respectively. Only 5/42 patients with ILD were not correctly classified by VECTOR, while false positive cases were 21.4%. No significant differences were observed according to the radiologic pattern of ILD.

Conclusion

VECTOR showed high sensitivity, specificity and diagnostic accuracy, allowing selecting patients to be investigated with HRCT. The relatively high frequency rate of false positive results is acceptable if compared with the lack of effective screening methods for this complication of CTDs.

Nailfold Videocapillaroscopy is a Useful Tool to Recognize Definite Forms of Systemic Sclerosis and Idiopathic Inflammatory Myositis in Interstitial Lung Disease Patients

Nailfold videocapillaroscopy (NVC) is an easy tool used for the assessment of patients with Raynaud's phenomenon (RP) as possibly associated with systemic sclerosis (SSc). Recent insights have also highlighted its role in the diagnostic assessment of idiopathic inflammatory myopathies (IIMs). The aim of this study is to describe the diagnostic role of NVC in a series of 361 consecutive patients with interstitial lung disease (ILD). All the patients were assessed by clinical pulmonary and rheumatic examinations, blood exams, high-resolution computed tomography and NVC. NVC was considered positive only in the presence of avascular areas or giant capillaries, but also, the presence of bushy capillaries (BCs) was recorded. NVC was positive in 17.7% of ILD patients and in 78.1% of ILD patients associated with a diagnosis of connective tissue disease (CTD). In 25% of SSc-ILD patients, NVC proved necessary for a correct diagnosis. The presence of BCs and/or NVC positivity in ILD patients with normal levels of creatine phosphokinase is associated with amyopathic IIM, regardless the presence of RP. In conclusion, NVC is useful for the diagnostic assessment of incomplete forms of CTD and in amyopathic IIMs. NVC should be considered in the diagnostic assessment of ILD patients regardless of the presence of RP.

Quantification of Ground Glass Opacities Can Be Useful to Describe Disease Activity in Systemic Sclerosis

Interstitial lung disease (ILD) is the main cause of death in systemic sclerosis (SSc) patients. Usually, patients have lung involvement characterized by ground glass opacities (GGOs), but honeycombing (HC) is also possible. The Wells score is a semi-quantitative index, which is able to assess ILD by distinguishing its main components. The aim of this work is to evaluate the Wells score in relation to the disease activity (DA) index. We enrolled 40 consecutive SSc-ILD patients (26 diffuse cutaneous form, dcSSc, and 14 limited form, lcSSc). All patients were evaluated by the European Scleroderma Study Group (ESSG) index, high-resolution computed tomography, transthoracic echocardiogram, pulmonary function tests (PTSs), and nailfold videocapillaroscopy for the number of microhemorrhages (NEMO) score. In our study, the total extent of ILD (TE-ILD), fibrosis and GGOs correlated with dyspnea (p = 0.03, 0.01 and 0.01 respectively), but not with the ESSG index. Considering only the dcSSc patients, TE-ILD and GGOs correlated with the ESSG index (r = 0.5 p = 0.009), while fibrosis grade correlated with disease duration and systolic pulmonary artery pressure. In conclusion, our data suggest that GGO correlates with DA, while fibrosis may be a sign of disease damage. The quantification of pulmonary involvement using the Wells score can be a useful tool for assessing the appropriate treatment in SSc patients.

Patients with Interstitial Lung Disease Secondary to Autoimmune Diseases: How to Recognize Them?

The diagnostic assessment of patients with Interstitial Lung Disease (ILD) can be challenging due to the large number of possible causes. Moreover, the diagnostic approach can be limited by the severity of the disease, which may not allow invasive exams. To overcome this issue, the referral centers for ILD organized Multidisciplinary Teams (MDTs), including physicians and experts in complementary discipline, to discuss the management of doubtful cases of ILD. MDT is currently considered the gold standard for ILD diagnosis, but it is not often simple to organize and, furthermore, rheumatologists are still not always included. In fact, even if rheumatologic conditions represent a common cause of ILD, they are sometimes difficult to recognize, considering the variegated clinical features and their association with all possible radiographic patterns of ILD. The first objective of this review is to describe the clinical, laboratory, and instrumental tests that can drive a diagnosis toward a possible rheumatic disease. The secondary objective is to propose a set of first-line tests to perform in all patients in order to recognize any possible rheumatic conditions underlying ILD.

Quantitative assessment of interstitial lung disease in Sjögren's syndrome

BACKGROUND

Interstitial lung disease (ILD) is a frequent manifestation of Sjögren's syndrome (SS), an autoimmune disease of salivary and lacrimal glands, and affects approximately 20% of patients. No clinical or serological features appear to be useful to predict its presence, severity or progression, and chest high-resolution computed tomography (CT) remains the gold standard for diagnosis. Semiquantitative CT (SQCT) based on visual assessment (Goh and Taouli scoring) can estimate ILD extent, although it is burdened by relevant intra- and interobserver variability. Quantitative chest CT (QCT) is a promising alternative modality to assess ILD severity.

AIM

To determine whether QCT assessment can identify extensive or limited lung disease in patients with SS and ILD.

METHODS

This multi-center, cross-sectional and retrospective study enrolled patients with SS and a chest CT scan. SQCT assessment was carried out in a blinded and centralized manner to calculate both Goh and Taouli scores. An operator-independent analysis of all CT scans with the open-source software platform Horos was used to evaluate the QCT indices. Patients were classified according to the extent of ILD and differences in QCT index distribution were investigated with non-parametric tests.

RESULTS

From a total of 102 consecutive patients with SS, the prevalence of ILD was 35.3% (36/102). There was a statistically significant difference in QCT index distribution between the SS with ILD and SS without ILD groups (p<0.001). Moreover, SS-ILD patients with ILD >20% (by Goh score) had a QCT index statistically different from those with limited ILD extent (p<0.001). Finally, QCT indices showed a moderate-to-good correlation with the Goh and Taouli scores (from 0.44 to 0.65; p<0.001).

CONCLUSIONS

QCT indices can identify patients with SS and ILD and discriminate those with lesser or greater lung disease.