State of the art in interstitial pneumonia with autoimmune features: a systematic review on retrospective studies and suggestions for further advances

Recognition of Idiopathic Inflammatory Myopathies Underlying Interstitial Lung Diseases

Interstitial Lung Disease (ILD) is one of the most common causes of mortality in idiopathic Inflammatory Myopathies (IIM). Despite these conditions being commonly associated with proximal weakness, skin rashes and arthritis, ILD can be the first or the sole clinical feature in up to 60% of patients, potentially leading to incorrect diagnosis. The early recognition of an underlying IIM in ILD patients can allow for prompt treatment, which could potentially stabilize or even improve the lung disease, also avoiding the development of other clinical features associated with the condition. The objective of this review is to describe the clinical, serological and radiological features associated with IIM-ILD, mainly focusing on dermatomyositis and antisynthetase syndrome.

Assessment of the Predictive Ability of the Neutrophil-to-Lymphocyte Ratio in Patients with In-Stent Restenosis after COVID-19

BACKGROUND

The neutrophil-to-lymphocyte ratio (NLR) is an independent predictor of the severity of coronary heart disease and COVID-19. This study aims to assess the predictive ability of the NLR in patients with in-stent restenosis after COVID-19.

MATERIALS AND METHODS

a cross-sectional study included 931 patients who underwent repeated myocardial revascularization between May 2020 and May 2023. The 420 patients of the main group had in-stent restenosis, of which 162 patients had COVID-19 previously. The control group included 511 patients without stent restenosis (107 patients had COVID-19 previously). All reported events were verified by hospital electronic records from the Complex Medical Information System.

RESULTS

The mean values of the NLR were 2.51 and 2.68 in the study groups, respectively. A statistically significant positive relationship in both groups was found between the NLR and troponin, D-dimer, C-reactive protein, creatinine, ALT, and AST. A statistically significant positive relationship was found between NLR and myocardial infarction (MI) in patients of both groups (p = 0.004; p < 0.001, respectively) and a negative relationship with the ejection fraction (p = 0.001; p < 0.036, respectively). An evaluation of the predictive ability of the clinical and laboratory predictors of recurrent myocardial infarction shows a high degree of utility of this model. The area under the ROC curve for AUC for NLR was 0.664 with 95% CI from 0.627 to 0.700 (p < 0.001).

CONCLUSIONS

NLR is one of the significant factors for predicting the development of adverse outcomes in patients with revascularized myocardium after COVID-19.

The Evolving Concept of the Multidisciplinary Approach in the Diagnosis and Management of Interstitial Lung Diseases

BACKGROUND

Interstitial lung diseases (ILDs) are a group of heterogeneous diseases characterized by inflammation and/or fibrosis of the lung interstitium, leading to a wide range of clinical manifestations and outcomes. Over the years, the literature has demonstrated the increased diagnostic accuracy and confidence associated with a multidisciplinary approach (MDA) in assessing diseases involving lung parenchyma. This approach was recently emphasized by the latest guidelines from the American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Latin American Thoracic Association for the diagnosis of ILDs.

METHODS

In this review, we will discuss the role, composition, and timing of multidisciplinary diagnosis (MDD) concerning idiopathic pulmonary fibrosis, connective tissue disease associated with ILDs, hypersensitive pneumonia, and idiopathic pneumonia with autoimmune features, based on the latest recommendations for their diagnosis.

RESULTS

The integration of clinical, radiological, histopathological, and, often, serological data is crucial in the early identification and management of ILDs, improving patient outcomes. Based on the recent endorsement of transbronchial cryo-biopsy in idiopathic pulmonary fibrosis guidelines, an MDA helps guide the choice of the sampling technique, obtaining the maximum diagnostic performance, and avoiding the execution of more invasive procedures such as a surgical lung biopsy. A multidisciplinary team should include pulmonologists, radiologists, pathologists, and, often, rheumatologists, being assembled regularly to achieve a consensus diagnosis and to review cases in light of new features.

CONCLUSIONS

The literature highlighted that an MDA is essential to improve the accuracy and reliability of ILD diagnosis, allowing for the early optimization of therapy and reducing the need for invasive procedures. The multidisciplinary diagnosis of ILDs is an ongoing and dynamic process, often referred to as a "working diagnosis", involving the progressive integration and re-evaluation of clinical, radiological, and histological features.

Functional respiratory impairment and related factors in patients with interstitial pneumonia with autoimmune features (IPAF): Multicenter study from NEREA registry

BACKGROUND

The objective of the present study is to describe the characteristics of interstitial pneumonia with autoimmune features (IPAF) patients, to assess the incidence rate of functional respiratory impairment over time and to evaluate the influence of therapeutic alternatives on the prognosis of these patients.

METHODS

A longitudinal observational multicenter study was performed (NEREA registry). It was carried out by a multidisciplinary team in seven Hospitals of Madrid. Patients were included from IPAF diagnosis.

MAIN OUTCOME

poor prognosis as functional respiratory impairment (relative decline in FVC % defined as ≥ 5% every 6 months). Covariates: therapy, sociodemographic, clinical, radiological patterns, laboratory and functional tests.

STATISTICS

Survival techniques were used to estimate IR per 100 patients-semester with their 95% confidence interval [CI]. The influence of covariates in prognosis were analyzed through cox multivariate regression models (hazard ratio (HR) and [CI]).

RESULTS

79 IPAF were included, with a mean and a maximum follow-up of 3.17 and 12 years respectively. Along the study, 77.2% received treatment (52 glucocorticoids, 25 mycophenolate, 21 azathioprine, 15 rituximab and 11 antifibrotics). IR was 23.9 [19.9-28.8], and 50% of IPAF developed functional respiratory impairment after 16 months from its diagnosis. Multivariate analysis: usual interstitial pneumonia (UIP) had poorer prognosis compared to non-specific interstitial pneumonia (NSIP) (p = 0.001). In NSIP, positive ANA, increased the risk of poor prognosis. In UIP, glucocorticoids (HR: 0.53 [0.34-0.83]), age (HR: 1.04 [1.01-1.07]), and Ro-antibodies (HR: 0.36 [0.19-0.65]) influenced the prognosis.

CONCLUSIONS

IPAF have functional impairment during the first years of disease. Factors predicting deterioration differ between radiographic patterns. Our real-life study suggests the potential benefit of particular therapies in IPAF.

Autoimmune Progressive Fibrosing Interstitial Lung Disease: Predictors of Fast Decline

A subset of interstitial lung diseases (ILDs) with autoimmune traits-including connective tissue disease-associated ILD (CTD-ILD) and interstitial pneumonia with autoimmune features (IPAF)-develops progressive fibrosing (PF)-ILD. The aim of our study was to evaluate the clinical characteristics and predictors of longitudinal lung function (LF) changes in autoimmune PF-ILD patients in a real-world setting. All ILD cases with confirmed or suspected autoimmunity discussed by a multidisciplinary team (MDT) between January 2017 and June 2019 (n = 511) were reviewed, including 63 CTD-ILD and 44 IPAF patients. Detailed medical history, LF test, diffusing capacity of the lung for carbon monoxide (DLCO), 6-min walk test (6MWT), blood gas analysis (BGA), and high-resolution computer tomography (HRCT) were performed. Longitudinal follow-up for functional parameters was at least 2 years. Women were overrepresented (70.1%), and the age of the IPAF group was significantly higher as compared to the CTD-ILD group (p < 0.001). Dyspnea, crackles, and weight loss were significantly more common in the IPAF group as compared to the CTD-ILD group (84.1% vs. 58.7%, p = 0.006; 72.7% vs. 49.2%, p = 0.017; 29.6% vs. 4.8%, p = 0.001). Forced vital capacity (FVC) yearly decline was more pronounced in IPAF (53.1 ± 0.3 vs. 16.7 ± 0.2 ml; p = 0.294), while the majority of patients (IPAF: 68% and CTD-ILD 82%) did not deteriorate. Factors influencing progression included malignancy as a comorbidity, anti-SS-A antibodies, and post-exercise pulse increase at 6MWT. Antifibrotic therapy was administered significantly more often in IPAF as compared to CTD-ILD patients (n = 13, 29.5% vs. n = 5, 7.9%; p = 0.007), and importantly, this treatment reduced lung function decline when compared to non-treated patients. Majority of patients improved or were stable regarding lung function, and autoimmune-associated PF-ILD was more common in patients having IPAF. Functional decline predictors were anti-SS-A antibodies and marked post-exercise pulse increase at 6MWT. Antifibrotic treatments reduced progression in progressive fibrosing CTD-ILD and IPAF, emphasizing the need for guidelines including optimal treatment start and combination therapies in this special patient group.

Clinical spectrum of children with interstitial pneumonia with autoimmune features

BACKGROUND

Interstitial pneumonia with autoimmune features (IPAF) is a term used to describe adult patients with interstitial lung disease (ILD) who display some clinical or serological features of autoimmune diseases and who do not meet the full criteria for a specific connective tissue disease (CTD). The aim of this study was to define the demographic, clinical, radiologic, serologic and histopathologic features and assess treatment in children with IPAF.

METHODS

This retrospective cohort study was conducted at a tertiary referral pediatric pulmonology center between January 2010 and August 2020. Children with proven interstitial pneumonia with no known etiologies were evaluated for IPAF according to European Respiratory Society/American Thoracic Society research statement of IPAF.

RESULTS

Among 132 children with ILD, 17 patients were evaluated in detail for IPAF criteria and six patients were further diagnosed as having IPAF. The incidence of IPAF in our patients with ILD was 4.5%. Four of these patients were female. The median age at the time of ILD diagnosis was 10.5 years. The most common initial symptom was shortness of breath, and the most common physical examination sign was crackles in both lungs. Steroid therapy was given to all patients and four patients received other immunosuppressive agents for steroid sparing. Two of those patients died because of respiratory insufficiency during the follow-up.

CONCLUSION

Children with interstitial pneumonia and certain clinical, serologic, and/or morphologic features should raise suspicion for the presence of an underlying systemic autoimmune disease. IPAF is also seen in children and should be categorized in chILD classifications.

Acute myocarditis with autoimmune features: one-year follow-up with CMR

In this prospective study on patients with acute myocarditis (AM), we aimed to describe the new concept of AMAF (AM with autoimmune features) similar to the previously described interstitial pneumonia with autoimmune features (IPAF). IPAF has recently emerged as a new entity, and IPAF patients appear to have fewer episodes of exacerbation and better survival than patients with idiopathic pulmonary fibrosis. Consecutive patients with infarct-like CMR-confirmed AM were classified AMAF if their serologic status measured from blood sampled at presentation was positive (antinuclear antibodies (ANA) ≥ 1:320), but without meeting established classification criteria for connective tissue disease (CTD). The myocardial tissue abnormalities and their progression were assessed on cardiac magnetic resonance (CMR) within 7 days following symptom onset and at 1 year according to their seropositivity. Among the 64 AM patients included, seven presented AMAF (11%). At baseline CMR, patients with AMAF had half as much late gadolinium enhancement (LGE) as seronegative AM patients (4.41% (1.47-4.41) of myocardial volume versus 8.82% (5.88-14.71), p = 0.01, respectively). At 1-year of follow-up, persistent myocardial scarring was less frequent in AMAF patients (n = 2 (28.6%) than seronegative AM patients (n = 38 (66.7%) (p = 0.021). AMAF, diagnosed as seropositive AM without a specific autoimmune disease, is not rare and is associated with less extensive LGE in the acute phase. In addition, AMAF patients had more favorable outcomes on 12-month CMR. Prospective studies are needed to address the clinical significance of this new concept and its long-term cardiovascular impact.

Interstitial pneumonia with autoimmune features: from research classification to diagnosis

PURPOSE OF REVIEW

The term interstitial pneumonia with autoimmune features (IPAF) was first proposed by an international task force in 2015 as a research classification to standardise nomenclature regarding patients with idiopathic interstitial pneumonia and features of connective tissue disease. However, how the use of this term and its proposed definition translates to clinical practice remains uncertain. This review will provide a comprehensive overview of studies of IPAF cohorts to date, discuss the consideration of IPAF as a distinct diagnostic entity and outline a suggested approach to patient management.

RECENT FINDINGS

Considerable heterogeneity exists between published IPAF cohorts, with some cohorts exhibiting similarities to those with connective tissue disease-associated interstitial lung disease (CTD-ILD), and others more similar to idiopathic interstitial pneumonias including idiopathic pulmonary fibrosis (IPF). Little data exist to inform the management of patients who fulfil the IPAF criteria. Preliminary data supports pragmatic management of these patients as having a working clinical diagnosis of either idiopathic interstitial pneumonia or CTD-ILD. Future research studies into this approach are required.

SUMMARY

The term IPAF, and its definition, have been of fundamental benefit to facilitating research in this diverse patient group. However, to date, there remain many unanswered questions regarding their natural histories and response to treatment.

Detection and Management of Interstitial Lung Diseases Associated With Connective Tissue Diseases

Interstitial lung disease (ILD) is a common manifestation of connective tissue diseases (CTDs). A proportion of patients with CTD-ILDs develop progressive fibrosing ILD, which is characterized by worsening fibrotic abnormalities on high-resolution computed tomography scan, decline in lung function, worsening symptoms, and early mortality. Here, we review the impact of ILD in patients with CTDs, the importance of prompt diagnosis and close monitoring, and the evidence available to guide the management of CTD-ILDs. Management of patients with CTD-ILDs should be individualized and involve close collaboration between rheumatologists and pulmonologists. Immunosuppression is the mainstay of therapy for CTDs, but evidence for its effectiveness in slowing the progression of ILD is limited. Recently, nintedanib has been approved to slow decline in lung function in patients with systemic sclerosis-associated ILD and chronic fibrosing ILDs with a progressive phenotype. The results of ongoing clinical trials will help clinicians take a more evidence-based approach to the treatment of CTD-ILDs.

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.

Interstitial pneumonia with autoimmune features: A case series and overview

The topic of interstitial pneumonia with autoimmune features (IPAF) is a research classification proposed by the European Respiratory Society/American Thoracic Society Task Force: this includes patients with idiopathic interstitial pneumonia (IIP) and clinical features, suggesting an underlying autoimmune process, but who do not meet established criteria for a connective tissue disease (CTD). We aimed to perform a detailed characterization of clinical, serological, and radiological features for our patients with IPAF criteria. Six patients were included, and a comprehensive description of these cases revealed a heterogeneous group in terms of clinical and treatment options. In most patients, it was possible to identify other features and disorders with an autoimmune “background,” which may support the inclusion of these patients in the IPAF classification. No deaths or significant decline in lung function occurred, and thus no definitive diagnosis of CTD could be found over 35 months of median follow-up. Therefore, IPAF is a recent concept, with many questions still open in regard to its usage in the ILD field.

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IPAF allows to group who presents with IIP and features suggesting an underlying autoimmune process, but do not meet criteria for a CTD.

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A detailed clinical history is crucial to identify other features or disorders with an autoimmune “background”.

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Our cases reveal a heterogeneous population, with a “benign” disease behavior, similar to CTD-ILD.

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The multidisciplinary meeting and follow-up are essential, so that an IPF diagnosis (if UIP pattern is present), or an evolution to CTD-ILD, are not missed.

Krebs von den Lungen-6 and surfactant protein-A in interstitial pneumonia with autoimmune features

Interstitial pneumonia with autoimmune features (IPAF) is a special subtype of interstitial lung disease that has received worldwide attention. Krebs von den Lungen-6 (KL-6) and surfactant protein-A (SP-A) can be used as an important biomarker of interstitial lung disease, but its exact relationship with IPAF is poorly understood.A total of 65 IPAF patients were included in the study and were followed up for 52 weeks. The KL-6 and SP-A were evaluated by chemiluminescence enzyme immunoassay. The above indicators were tested at 2 time points, baseline (the first admission of patients) and 52 weeks. We also collected the indicators of antinuclear antibodies and rheumatoid factor. Based on high-resolution computed tomography evaluations, patients were divided into: aggravation, stable, and improvement group. At same time, 30 age-matched normal people as normal control were recruited, the same information was collected. Correlations among the groups were compared and analyzed.The KL-6 and SP-A level in IPAF patients were significantly higher than normal controls (fold increase = 11.35 and 1.39, both P < .001) and differed significantly at baseline and 52 weeks in IPAF (difference ratio = 37.7% and 21.3%, P < .05, both). There were significant differences at baseline and 52 weeks (r values of aggravation, improvement, and stable groups for KL-6 were 0.705, 0.770, and 0.344, P = .001, .001, and .163, and for SP-A the r value were 0.672, 0.375, and 0.316, P = .001, .126, and .152). In aggravation group, KL-6 and SP-A were correlated with CT scores (both P < .05). Diffusing capacity of the lung for carbon monoxide (DLCO) and forced vital capacity (FVC), % predicted showed a progressive downward trend, with a significant difference at baseline and 52 weeks in IPAF patients (difference ratio = 23.8% and 20.6%, both P < .05). There was a significant correlation between KL-6 and FVC % predicted and DLCO (both P < .05), SP-A showed negatively correlated with DLCO, but not significantly correlated with FVC % predicted (P < .05 and .47).This study demonstrated that KL-6 and SP-A can reflect disease progression, and both 2 play a key role at reflection of lung epithelial cell injury and fibrosis degree in IPAF.

MPO-ANCA positive interstitial pneumonia: Current knowledge and future perspectives

Although interstitial pneumonia is an important respiratory manifestation in microscopic polyangiitis (MPA), no studies have examined the detailed pathogenesis of interstitial pneumonia during the clinical course of MPA. In addition, it is considered that MPA develops at a certain incidence rate from myeloperoxidase (MPO)- antineutrophil cytoplasmic antibody (ANCA) positive interstitial pneumonia. However, there is a lack of consensus among pulmonologist and rheumatologist regarding whether MPO-ANCA positive interstitial pneumonia, which does not accompany other organ damage related to ANCA-associated vasculitis (AAV) other than interstitial pneumonia, should be included in AAV. In this review article, the clinical questions regarding MPO-ANCA positive interstitial pneumonia have been set, and evidence to date and problems to be solved in future are outlined.

Interstitial Pneumonia with Autoimmune Features: Why Rheumatologist-Pulmonologist Collaboration Is Essential

In 2015 the European Respiratory Society (ERS) and the American Thoracic Society (ATS) “Task Force on Undifferentiated Forms of Connective Tissue Disease-associated Interstitial Lung Disease” proposed classification criteria for a new research category defined as “Interstitial Pneumonia with Autoimmune Features” (IPAF), to uniformly define patients with interstitial lung disease (ILD) and features of autoimmunity, without a definite connective tissue disease. These classification criteria were based on a variable combination of features obtained from three domains: a clinical domain consisting of extra-thoracic features, a serologic domain with specific autoantibodies, and a morphologic domain with imaging patterns, histopathological findings, or multicompartment involvement. Features suggesting a systemic vasculitis were excluded. Since publication of ERS/ATS IPAF research criteria, various retrospective studies have been published focusing on prevalence; clinical, morphological, and serological features; and prognosis of these patients showing a broad heterogeneity in the results. Recently, two prospective, cohort studies were performed, confirming the existence of some peculiarities for this clinical entity and the possible progression of IPAF to a defined connective tissue disease (CTD) in about 15% of cases. Moreover, a non-specific interstitial pneumonia pattern, an anti-nuclear antibody positivity, and a Raynaud phenomenon were the most common findings. In comparison with idiopathic pulmonary fibrosis (IPF), IPAF patients showed a better performance in pulmonary function tests and less necessity of oxygen delivery. However, at this stage of our knowledge, we believe that further prospective studies, possibly derived from multicenter cohorts and through randomized control trials, to further validate the proposed classification criteria are needed.

The Spectrum of Interstitial Lung Disease Associated with Autoimmune Diseases: Data of a 3.6-Year Prospective Study from a Referral Center of Interstitial Lung Disease and Lung Transplantation

Interstitial lung disease (ILD) may occur in patients with a rheumatic autoimmune disease (AD), increasing their risk of morbidity and mortality. However, little is known about the prevalence of AD in patients diagnosed with an ILD. In this prospective study, we determined the spectrum of ILD associated with AD (AD-ILD) among patients sent for assessment to a single clinic of ILD and lung transplantation from a referral center between May 2016 and December 2019. ILD diagnosis was made by pneumologists based on clinical and radiological findings and pulmonary function test abnormalities. All patients with ILD were also assessed by experienced rheumatologists. During the period of assessment, 338 patients were diagnosed with ILD. Among them, 32.8% fulfilled definitions for an AD. Most cases with AD-ILD had a diagnosis of rheumatoid arthritis (27.0%), systemic sclerosis (26.1%) or anti-synthetase syndrome (17.1%). Interestingly, 18% of the patients with AD-ILD were diagnosed as having an interstitial pneumonia with autoimmune features. Antinuclear antibodies and non-specific interstitial pneumonia were the most frequent positive autoantibodies and radiological pattern found in AD-ILD patients, respectively. In conclusion, our study indicates that a high number of ILD patients have a related AD. Consequently, close collaboration among rheumatologists and pneumologists is needed.

Evolution and treatment of idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a chronic and devastating disease of unknown etiology, characterized by irreversible morphological changes, ultimately leading to lung fibrosis and death. In recent years, significant progress has been achieved in understanding the pathogenesis of IPF. Moreover, we assisted to the conceptual change of the pathogenic hypothesis that currently considers IPF as a primarily fibrotic driven disease. However, despite the undeniable progress, the diagnosis of IPF remains still very complex requiring the presence of a team of experts to achieve the highest level of diagnostic confidence. The advent of antifibrotics has radically changed the treatment landscape of IPF and new promising drugs are currently under evaluation. Furthermore, a more extensive use of non-pharmacological treatments has also to be encouraged in all patients both to reduce symptoms and improve quality of life.

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.

Clinical significance of thyroid hormone and antibodies in patients with idiopathic interstitial pneumonia

Background

Hypothyroidism was recently reported to be common and to predict mortality in patients with idiopathic pulmonary fibrosis (IPF). In addition, a high prevalence of hypothyroidism was shown in patients with idiopathic pleuroparenchymal fibroelastosis. However, in idiopathic interstitial pneumonia (IIP), a clinical significance of thyroid function has not been clarified in detail. The goal of this study was to investigate the clinical significance of thyroid function and the presence of thyroid antibodies in IIP.

Methods

We have reviewed IIP patients, and analyzed the positivity of thyroid antibodies at first. Next, the relationship of clinical characteristics with thyroid function and the positivity of thyroid antibodies was analyzed. Lastly, the positivity of thyroid antibodies and other autoantibodies was evaluated.

Results

In IIP patients, thyroglobulin and thyroid peroxidase antibodies were positive in 17 and 16%, respectively, and 22% of patients had either or both antibodies. Subclinical and/or overt hypothyroidism was confirmed in 7% of IIP patients. The free thyrotropin level had a significant positive correlation with vital capacity and a significant negative correlation with the C-reactive protein and surfactant protein-A levels, and erythrocyte sedimentation ratio (ESR). In addition, autoantibodies suggestive of connective tissue diseases (CTDs) were positive in more than two thirds of IIP patients with the thyroid antibody, and the positive rate of antinuclear and proteinase-3 anti-neutrophil cytoplasmic antibodies was significantly higher in IIP patients with thyroid antibodies than those without the antibodies.

Conclusions

Although thyroid dysfunction is not frequent, thyroid hormones and thyroid antibodies are possibly involved in the pathogenesis of IIP and their evaluation may be clinically useful to identify the clinical phenotype of IIP with autoimmune features.

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.

Multidisciplinary Approach in the Early Detection of Undiagnosed Connective Tissue Diseases in Patients With Interstitial Lung Disease: A Retrospective Cohort Study

Interstitial lung disease (ILD) encompasses a wide range of parenchymal lung pathologies with different clinical, histological, radiological, and serological features. Follow-up, treatment, and prognosis are strongly influenced by the underlying pathogenesis. Considering that an ILD may complicate the course of any connective tissue disease (CTD) and that CTD's signs are not always easily identifiable, it could be useful to screen every ILD patient for a possible CTD. The recent definition of interstitial pneumonia with autoimmune features is a further confirmation of the close relationship between CTD and ILD. In this context, the multidisciplinary approach is assuming a growing and accepted role in the correct diagnosis and follow-up, to as early as possible define the best therapeutic strategy. However, despite clinical advantages, until now, the pathways of the multidisciplinary approach in ILD patients are largely heterogeneous across different centers and the best strategy to apply is still to be established and validated. Aims of this article are to describe the organization of our multidisciplinary group for ILD, which is mainly focused on the early identification and management of CTD in patients with ILD and to show our results in a 1 year period of observation. We found that 15% of patients referred for ILD had an underlying CTD, 33% had interstitial pneumonia with autoimmune feature, and 52% had ILD without detectable CTD. Furthermore, we demonstrated that the adoption of a standardized strategy consisting of a screening questionnaire, specific laboratory tests, and nailfold videocapillaroscopy in all incident ILD proved useful in making the right diagnosis.

Inflammatory Myopathy-Related Interstitial Lung Disease: From Pathophysiology to Treatment

Inflammatory myopathies (IM) are auto-immune connective tissue diseases characterized by muscle involvement and by extramuscular manifestations. As such, pulmonary manifestations, which mainly include interstitial lung disease (ILD), often darken two out of four distinct IM, namely dermatomyositis and overlapping myositis. Being the initiation site of the disease and being the leading cause of morbidity and mortality, ILD is of major importance in this context. ILD has a heterogeneous expression among the patients, with various onset mode, various radiological pattern, various severity and finally with different prognoses, which are particularly difficult to predict at the time of IM diagnosis. Therefore, ILD is a challenging issue. Treatments are based on steroids and immunosuppressive or targeted therapies. Their respective place is yet poorly codified however and remains often based on clinician expertise. Dedicated clinical trials are lacking to date and are also difficult to build, due to difficulty of constituting large and homogeneous patient groups and to rigorously evaluate disease outcomes. Indeed, pulmonary function tests alone are being regularly defeated in IM, in which respiratory muscles are often involved. Composite scores, bringing together several lung parameters, should thus be developed and validated in the future, to better assess the disease response to treatment. This review aims to describe the current knowledge of IM immuno-pathogenesis, the clinical features associated with IM related-ILD, focusing of both severity and prognosis, and the actual therapeutic approaches.

Interstitial pneumonia with autoimmune features: A single center prospective follow-up study

BACKGROUND AND OBJECTIVE

Recently the term "interstitial pneumonia with autoimmune features" (IPAF) has been proposed to identify patients with interstitial lung disease and autoimmune characteristics, not fulfilling the criteria for specific connective tissue diseases (CTD). Only few data are available about the clinical and serological features of IPAF patients, their survival and the possible evolution in a CTD. The aims of the study were to investigate the demographic and clinico-serologic features of patients with IPAF, their relationship to survival, and the possible evolution in a definite CTD.

PATIENTS AND METHODS

Fifty-two patients were consecutively enrolled and prospectively followed for 45 ± 31.6 months. Data about disease onset, serological, clinical and therapeutic features, pulmonary function tests and high-resolution computed tomography were periodically repeated. The survival of patients with IPAF was compared with that of 104 patients with idiopathic pulmonary fibrosis (IPF).

RESULTS

The clinical domain for IPAF was satisfied in 44 patients, serological domain in 49 and the morphological domain in 29 patients. During the follow-up, a definite CTD was diagnosed in 7 patients, in particular Sjogren's syndrome in 4 patients, rheumatoid arthritis in 2, and polymyositis in the last. The estimated 5-year survival of IPAF patients 69.5 ± 7.8%, significantly higher than survival observed in IPF patients, and the baseline value of FVC and DLCO were the only factors associated to death.

CONCLUSIONS

IPAF seems to a distinct entity, with a low tendency to evolve in a definite CTD. Nevertheless, further studies are needed to better define the clinical evolution and the outcome of IPAF.

Systematic review and meta-analysis of the prognosis and prognostic factors of interstitial pneumonia with autoimmune features

OBJECTIVE

To clarify the prognosis and prognostic factors of interstitial pneumonia with autoimmune features (IPAF) in comparison to idiopathic pulmonary fibrosis (IPF), the most common idiopathic interstitial pneumonia, and connective tissue disease-associated interstitial pneumonia (CTD-IP).

DESIGN

A systematic review and meta-analysis.

DATA SOURCES

Electronic databases such as Medline and Embase were searched from 2015 through 6 September 2019.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Primary studies that comparatively investigated the prognosis or prognostic factors of IPAF were eligible.

DATA EXTRACTION AND ANALYSIS

Two reviewers extracted relevant data and assessed the risk of bias independently. A meta-analysis was conducted using a random-effects model. The quality of presented evidence was assessed by the Grades of Recommendation, Assessment, Development, and Evaluation system.

RESULTS

Out of a total of 656 records retrieved, 12 studies were reviewed. The clinical features of IPAF were diverse between studies, which included a radiological and/or pathological usual interstitial pneumonia (UIP) pattern of between 0% and 73.8%. All studies contained some risk of bias. There was no significant difference of all-cause mortality between IPAF-UIP and IPF in all studies, although the prognosis of IPAF in contrast to IPF or CTD-IP varied between studies depending on the proportion of UIP pattern. Among the potential prognostic factors identified, age was significantly associated with all-cause mortality of IPAF by a pooled analysis of univariate results with a hazard ratio (HR) of 1.06 (95% confidence interval (CI) 1.04 to 1.07). The adjusted effect of age was also significant in all studies. The quality of presented evidence was deemed as very low.

CONCLUSION

There was no significant difference of all-cause mortality between IPAF-UIP and IPF. Age was deemed as a prognostic factor for all-cause mortality of IPAF. The findings should be interpreted cautiously due to the low quality of the presented evidence.

PROSPERO REGISTRATION NUMBER

CRD42018115870.

Possible value of antifibrotic drugs in patients with progressive fibrosing non-IPF interstitial lung diseases

BACKGROUND

Fibrosing, non-idiopathic pulmonary fibrosis (non-IPF) interstitial lung diseases (fILDs) are a heterogeneous group of diseases characterized by a different amount of inflammation and fibrosis. Therapy is currently based on corticosteroids and/or immunomodulators. However, response to these therapies is highly variable, sometimes without meaningful improvement, especially in more fibrosing forms. Pirfenidone and nintedanib have recently demonstrated to reduce functional decline in patients with IPF. However, their antifibrotic mechanism makes these two drugs an interesting approach for treatment of fibrosing ILDs other than IPF.

OBJECTIVES

We here report our experience with antifibrotic drugs in fibrosing non-IPF ILDs patients having a progressive phenotype during immunosuppressive therapy.

METHODS

Patients with a multidisciplinary team diagnosis of fibrosing non-IPF ILDs experiencing a progressive phenotype during treatment with corticosteroids and/or immunomodulators between October-2014 and January-2018 at our tertiary referral Center for ILDs were retrospectively analyzed. Antifibrotic therapy was administered after application with the respective health insurance company and after consent by the patient. Pulmonary-function-tests and follow-up visits were performed every 6 ± 1 months.

RESULTS

Eleven patients were treated with antifibrotic drugs (8 males, mean age 62 ± 12.8 years, mean FVC% 62.8 ± 22.3, mean DLCO% 35.5 ± 10.7, median follow-up under antifibrotic treatment 11.1 months). Patients had a diagnosis of unclassifiable ILD in 6 cases, pleuroparenchymal fibroelastosis in 2 cases, idiopathic-NSIP in 1 case, asbestos-related ILD in 1 case and Hermansky-Pudlak syndrome in 1 case. Treatment before antifibrotics consisted of corticosteroids in all patients: 5 combined with Azathioprin, 1 with either methotrexate or cyclophosphamide (i.v.). Ten patients were treated with pirfenidone (2403 mg/die) and 1 with nintedanib (300 mg/die). Median FVC was 56, 56, 50%, at time points - 24, - 12, - 6 before initiation, 44% at time of initiation and 46.5% at 6 months after initiation of antifibrotic treatment. Antifibrotic treatment was generally well tolerated with a need of dose reduction in 2 cases (rash and nausea) and early termination in 3 cases.

CONCLUSIONS

Antifibrotic treatment may be a valuable treatment option in patients with progressive fibrosing non-IPF ILD if currently no other treatment options exist. However, prospective, randomized clinical trials are urgently needed to assess the real impact of antifibrotic therapy in these patients.

Idiopathic and immune-related pulmonary fibrosis: diagnostic and therapeutic challenges

Interstitial lung disease (ILD) encompasses a large group of pulmonary conditions sharing common clinical, radiological and histopathological features as a consequence of fibrosis of the lung interstitium. The majority of ILDs are idiopathic in nature with possible genetic predisposition, but is also well recognised as a complication of connective tissue disease or with certain environmental, occupational or drug exposures. In recent years, a concerted international effort has been made to standardise the diagnostic criteria in ILD subtypes, formalise multidisciplinary pathways and standardise treatment recommendations. In this review, we discuss some of the current challenges around ILD diagnostics, the role of serological testing, especially, in light of the new classification of Interstitial Pneumonia with Autoimmune Features (IPAF) and discuss the evidence for therapies targeted at idiopathic and immune-related pulmonary fibrosis.

The Role of the Multidisciplinary Evaluation of Interstitial Lung Diseases: Systematic Literature Review of the Current Evidence and Future Perspectives

The opportunity of a multidisciplinary evaluation for the diagnosis of interstitial pneumonias highlighted a major change in the diagnostic approach to diffuse lung disease. The new American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Latin American Thoracic Society guidelines for the diagnosis of idiopathic pulmonary fibrosis have reinforced this assumption and have underlined that the exclusion of connective tissue disease related lung involvement is mandatory, with obvious clinical and therapeutic impact. The multidisciplinary team discussion consists in a moment of interaction among the radiologist, pathologist and pulmonologist, also including the rheumatologist when considered necessary, to improve diagnostic agreement and optimize the definition of those cases in which pulmonary involvement may represent the first or prominent manifestation of an autoimmune systemic disease. Moreover, the proposal of classification criteria for interstitial lung disease with autoimmune features (IPAF) represents an effort to define lung involvement in clinically undefined autoimmune conditions. The complexity of autoimmune diseases, and in particular the lack of classification criteria defined for pathologies such as anti-synthetase syndrome, makes the involvement of the rheumatologist essential for the correct interpretation of the autoimmune element and for the application of classification criteria, that could replace clinical pictures initially interpreted as IPAF in defined autoimmune disease, minimizing the risk of misdiagnosis. The aim of this review was to evaluate the available evidence about the efficiency and efficacy of different multidisciplinary team approaches, in order to standardize the professional figures and the core set procedures that should be necessary for a correct approach in diagnosing patients with interstitial lung disease.

Antifibrotic therapy for fibrotic lung disease beyond idiopathic pulmonary fibrosis

Two antifibrotic medications (nintedanib and pirfenidone) were recommended (conditionally) for the treatment of patients with idiopathic pulmonary fibrosis (IPF) in the 2015 IPF evidence-based guidelines. These medications have been shown to reduce the rate of decline in forced vital capacity among patients with IPF over time and are the only two disease-modulating pharmacological agents approved by regulatory agencies and available for clinical use worldwide. With the evolved standard of care for interstitial lung disease evaluation including routine use of high-resolution computed tomography, fibrotic lung diseases other than IPF are increasingly recognised. In addition, it is becoming evident that genetic and pathophysiological mechanisms as well as disease behaviour in patients manifesting other "non-IPF progressive fibrotic interstitial lung diseases" (non-IPF-PF) may be similar to those in patients with IPF. Thus, it is biologically plausible that pharmacological agents with antifibrotic properties may be efficacious in non-IPF-PF. Indeed, studies are underway or planned to assess the safety and efficacy of nintedanib or pirfenidone among patients with several non-IPF fibrotic lung diseases. In this review, we briefly summarise the use of pirfenidone and nintedanib in IPF as well as the rationale and potential for use of these medications in non-IPF-PF that are being investigated in ongoing and upcoming clinical trials.

Interstitial pneumonia with autoimmune features and platypnea-orthopnea syndrome

Interstitial pneumonia with autoimmune features (IPAF) is a recently proposed terminology for interstitial lung disease (ILD) with evidence of autoimmunity that does not meet the criteria for a defined connective tissue disease (CTD). Although ILD is well recognised in patients with established CTD, it is rarely the sole presenting feature of CTD. We report a case of 22-year-old male patient, who presented with progressive shortness of breath for 2 months and had features suggestive of platypnea-orthodeoxia syndrome (POS). Imaging revealed ILD with usual interstitial pneumonia pattern. Patient had features of autoimmune disorder but did not fulfil the criteria for any CTD and hence was labelled as IPAF. His POS was attributed predominantly to the lower lobe disease. The patient responded well to immunosuppressive treatment. A systematic review of literature of all cases with POS due to pulmonary parenchymal involvement has also been done.

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

Introduction

Connective Tissue Diseases (CTDs) are systemic autoimmune conditions characterized by frequent lung involvement. This usually takes the form of Interstitial Lung Disease (ILD), but Obstructive Lung Disease (OLD) and Pulmonary Artery Hypertension (PAH) can also occur. Lung involvement is often severe, representing the first cause of death in CTD. The aim of this study is to highlight the role of Pulmonary Function Tests (PFTs) in the diagnosis and follow up of CTD patients.

Main body

Rheumatoid Arthritis (RA) showed mainly an ILD with a Usual Interstitial Pneumonia (UIP) pattern in High-Resolution Chest Tomography (HRCT). PFTs are able to highlight a RA-ILD before its clinical onset and to drive follow up of patients with Forced Vital Capacity (FVC) and Carbon Monoxide Diffusing Capacity (DL_CO). In the course of Scleroderma Spectrum Disorders (SSDs) and Idiopathic Inflammatory Myopathies (IIMs), DL_CO appears to be more sensitive than FVC in highlighting an ILD, but it can be compromised by the presence of PAH. A restrictive respiratory pattern can be present in IIMs and Systemic Lupus Erythematosus due to the inflammatory involvement of respiratory muscles, the presence of fatigue or diaphragm distress.

Conclusions

The lung should be carefully studied during CTDs. PFTs can represent an important prognostic tool for diagnosis and follow up of RA-ILD, but, on their own, lack sufficient specificity or sensitivity to describe lung involvement in SSDs and IIMs. Several composite indexes potentially able to describe the evolution of lung damage and response to treatment in SSDs are under investigation. Considering the potential severity of these conditions, an HRCT jointly with PFTs should be performed in all new diagnoses of SSDs and IIMs. Moreover, follow up PFTs should be interpreted in the light of the risk factor for respiratory disease related to each disease.

Cyclophosphamide pulse therapy as treatment for severe interstitial lung diseases

Introduction

Besides invasive or non-invasive ventilation, treatment of severe forms of interstitial lung diseases (ILD) includes immunosuppressive medication. In case of refractory organ- or life-threatening courses of disease, cyclophosphamide pulse therapy can serve as a rescue treatment option.

Objectives

To investigate therapeutic and prognostic effects of cyclophosphamide for the treatment of severe forms of ILD on intensive care unit (ICU) we performed this analysis.

Methods

Between 2009 and 2017 we identified 14 patients, who were treated on intensive care unit (ICU) with severe forms of ILD. Retrospectively, clinical, radiologic and prognostic data were collected and evaluated.

Results

Our analysis demonstrated a prognostic impact of cyclophosphamide on the ILD in general. Whereas pulmonary manifestations of both systemic sclerosis (SSc) and ANCA-associated vasculitis had an improved outcome, a reduced overall survival was found for Goodpasture syndrome (GPS), dermatomyositis (DM), cryptogenic organizing pneumonia (COP) and drug reaction with eosinophilia and systemic symptoms (DRESS; p=0.040, logrank test). Besides, additional plasmapheresis and initiation of cyclophosphamide within ten days following initial diagnosis of ILD were associated with improved prognosis.

Conclusion

Positive prognostic effects of cyclophosphamide pulse therapy in ICU treated patients suffering from severe respiratory failure due to pulmonary manifestations of both SSc and ANCA-associated-vasculitis were observed. Further prognostic and therapeutic data are needed for cyclophosphamide for this indication in order to prevent patients from its toxic side-effects, who most likely will not benefit from its application.

Fibrosing interstitial lung diseases: knowns and unknowns

Patients with certain types of fibrosing interstitial lung disease (ILD) are at risk of developing a progressive phenotype characterised by self-sustaining fibrosis, decline in lung function, worsening quality of life, and early mortality. It has been proposed that such progressive fibrosing ILDs, which show commonalities in clinical behaviour and in the pathogenetic mechanisms that drive progressive fibrosis, may be "lumped" together for the purposes of clinical research and, potentially, for treatment. At present, no drugs are approved for the treatment of ILDs other than nintedanib and pirfenidone for the treatment of idiopathic pulmonary fibrosis. For other progressive fibrosing ILDs, the mainstay of drug therapy is immunosuppression. However, it is postulated that, once the response to lung injury in fibrosing ILDs has reached the stage at which fibrosis has become progressive and self-sustaining, targeted antifibrotic therapy would be required to slow disease progression. Nintedanib, an intracellular inhibitor of tyrosine kinases, has shown antifibrotic, anti-inflammatory and vascular remodelling effects in several non-clinical models of fibrosis, irrespective of the trigger for the injury. Ongoing clinical trials will provide insight into the role of antifibrotic treatment with nintedanib or pirfenidone in the management of fibrosing ILDs with a progressive phenotype.

Strategy for suspected myositis

Skeletal muscle inflammation is the feature shared by all forms of myositis. However, the muscle damage ranges in severity from asymptomatic to responsible for severe weakness. In addition, myositis usually occurs as a systemic disease that affects multiple organs. More specifically myositis should be considered in patients with muscular, cutaneous, pulmonary, and articular manifestations. The definitive diagnosis and classification of myositis has benefited considerably in recent years from the identification of characteristic autoantibodies. Nonetheless, a muscle biopsy is often necessary to confirm the diagnosis, and the differential diagnoses may raise challenges that require evaluation at a myositis referral center. The management depends on the type of myositis. Treatments should be provided for both the systemic complications (involving the lungs, heart, gastrointestinal tract, and/or joints) and the comorbidities (cancer and risks factors for cardiovascular disease, thromboembolism, and fractures), which together determine the prognosis. Many drugs are available for treating myositis. Findings from randomized controlled trials will help to use them optimally.

Interstitial Lung Disease in patients with Polymyalgia Rheumatica: A case series

INTRODUCTION

Severe morning stiffness with painful involvement of the girdles are often referred by patients with Interstitial Lung Disease (ILD), but the association between ILD and Polymyalgia Rheumatica (PMR) is rarely reported. The purpose of the work is to describe a series of patients classified as having PMR with ILD.

MATERIAL AND METHODS

We retrospectively enrolled patients with a diagnosis of PMR referred to our center during the previous year for respiratory symptoms. Data concerning clinical and serological manifestations suggesting Connective Tissue Disease (CTD), High-Resolution Chest Tomography (HRCT), and Pulmonary Function Tests (PFTs) were systematically collected in order to verify the diagnosis.

RESULTS

Fifteen out of seventeen PMR patients had ILD. Ten patients had a confirmed diagnosis of PMR, while in five patients a CTD was discovered. Seven patients showed a severe restrictive pattern at PFTs requiring oxygen supplementation (five with PMR and two with CTD). In thirteen patients pulmonary symptoms started before or together with muscular symptoms. Regarding HRCT patterns, patients showed a Nonspecific Interstitial Pneumonia in nine cases, Usual Interstitial Pneumonia (UIP) and possible UIP in two and three cases, and a single case of Organizing Pneumonia and Combined Pulmonary Fibrosis and Emphysema Syndrome.

CONCLUSIONS

Lung involvement should be evaluated in PMR patients, especially if asthenia is poorly responsive to low doses of steroids. In these cases, the diagnosis should be re-evaluated in depth, looking for a seronegative Rheumatoid Arthritis, a clinically amyopathic myositis or Interstitial Pneumonia with Autoimmune features.

Interstitial pneumonia with autoimmune features: a new classification still on the move

In the past decade, the attention has been focused on the relationship between interstitial lung disease (ILD) and connective tissue diseases (CTDs). The clinical impact, as well as the therapeutic approach, classification and diagnosis have been addressed. These two latter items represent an area of great interest because the underlying conditions leading to ILD and the most appropriate treatment still needs to be defined. Recently, the European Respiratory Society/American Thoracic Society proposed the interstitial pneumonia with autoimmune features (IPAF) criteria which represents the effort of pulmonologists to classify patients that may remain clinically undefined [1]. The analysis of these criteria shows that IPAF, similarly to pulmonary arterial hypertension classification [2], may cluster conditions referring to a wide spectrum of rheumatic conditions such as systemic sclerosis, myositis, rheumatoid arthritis and overlap syndromes. These diseases are characterised by highly different characteristics, evolution and therapeutic approaches. Furthermore, IPAF criteria have an intrinsically changing structure, related to the regular update of existing CTD classification criteria and to the even more common identification of new biomarkers in CTDs. By far the most important effect of these criteria is the identification of a grey zone of not well-defined rheumatology conditions, e.g. anti-synthetase syndrome (ASSD) [3]. In this issue of the European Respiratory Review, Sambataroet al. [4] address the need to identify specific clinical characteristics and potential areas of improvement in IPAF patients. The starting point of the review is interesting because of the exclusion of papers that included patients diagnosed with ASSD, because no ASSD established classification criteria still exist. The authors' choice is related to the unique characteristics of ASSD, in which it is not unusual to observe the occurrence during follow-up of findings lacking at disease onset. [5]. However, as reported previously [6], in the case of anti-synthetase antibody positivity, the diagnostic scenario may vary with the same patient diagnosed with ASSD if referred to a rheumatologist, or IPAF if referred to a pulmonologist. In fact, a high prevalence of anti-synthetase antibody positivity is reported in the majority of papers evaluated by Sambataroet al. [4], thus confirming the fact that despite the presence of this antibody (identifying ASSD) patients may frequently end up being classified as having IPAF. However, some IPAF patients could not be tested for the entire spectrum of antibodies, probably due to the local unavailability of these tests, or because initial anti-Ro antibody positivity might have prompted the clinicians to evaluate further non-anti-Jo-1 myositis specific auto-antibodies. In fact, it is established that anti-Ro antibodies and anti-synthetase antibodies may co-occur in about 50% of cases, even when patients could be classified as IPAF [7]. Furthermore, we should also consider that if eight anti-synthetase antibodies have been identified to date, at least another 12 aminoacyl-tRNA synthetase enzymes exist, and that the entire spectrum of anti-synthetase antibodies is not covered by any of the existing commercially available tests. All these points clearly indicate the risk that anti-synthetase antibody positivity could be underestimated and that it could be clustered in IPAF. This evidence clearly suggests that well-established and clinically based ASSD classification criteria are needed to reduce the risk of stratifying patients across specialties, in areas that may contribute to real-time incorrectly diagnosed primary disease. Recently, the CLASS (classification criteria of anti-synthetase syndrome) project has been funded by the American College of Rheumatology and the European League against Rheumatism. The aim of the project is to define clinically based criteria of ASSD involving a large number of rheumatology, pulmonology, dermatology, immunology and internal medicine centres expert in the management of rheumatoid arthritis, systemic sclerosis, Sjogren's syndrome and other lung fibrosing conditions. From a scientific point of view, by putting together different specialists we hope to solve the daily discussions about “anti-synthetase antibody positive patient classification” that may delay the correct approach and treatment of affected patients.

IPAF classification criteria include several autoimmune conditions with different evolution. The progression into established CTD is common and a continuous up-to-date process of classification criteria of both IPAF and CTD is mandatory.http://ow.ly/pXNW30knUzl