Pulmonary Vascular Manifestations of Mixed Connective Tissue Disease

Evolution of diagnostic criteria and new insights into clinical testing in mixed connective tissue disease; anti-survival motor neuron complex antibody as a novel marker of severity of the disease

Mixed connective tissue disease (MCTD) is an autoimmune disorder characterized by a combination of clinical features from systemic lupus erythematosus, systemic sclerosis, and inflammatory muscle disease, along with the presence of positive anti-U1-ribonucleoprotein (U1-RNP) antibodies. The exact etiology of the disease remains unclear, but it is believed to involve vascular damage within the context of heightened autoimmune responses. Consequently, Raynaud's phenomenon and pulmonary arterial hypertension are observed in patients with MCTD. While specific biomarkers for MCTD have not yet been identified, the recent study of the utility of anti-survival motor neuron complex (SMN) antibodies in MCTD suggests a promising avenue for further research and the accumulation of additional evidence.

Immune-mediated lung diseases: A narrative review

The role of immunity in the pathogenesis of various pulmonary diseases, particularly interstitial lung diseases (ILDs), is being increasingly appreciated as mechanistic discoveries advance our knowledge in the field. Immune-mediated lung diseases demonstrate clinical and immunological heterogeneity and can be etiologically categorized into connective tissue disease (CTD)-associated, exposure-related, idiopathic, and other miscellaneous lung diseases including sarcoidosis, and post-lung transplant ILD. The immunopathogenesis of many of these diseases remains poorly defined and possibly involves either immune dysregulation, abnormal healing, chronic inflammation, or a combination of these, often in a background of genetic susceptibility. The heterogeneity and complex immunopathogenesis of ILDs complicate management, and thus a collaborative treatment team should work toward an individualized approach to address the unique needs of each patient. Current management of immune-mediated lung diseases is challenging; the choice of therapy is etiology-driven and includes corticosteroids, immunomodulatory drugs such as methotrexate, cyclophosphamide and mycophenolate mofetil, rituximab, or other measures such as discontinuation or avoidance of the inciting agent in exposure-related ILDs. Antifibrotic therapy is approved for some of the ILDs (e.g., idiopathic pulmonary fibrosis) and is being investigated for many others and has shown promising preliminary results. A dire need for advances in the management of immune-mediated lung disease persists in the absence of standardized management guidelines.

Interstitial Lung Disease in Mixed Connective Tissue Disease: An Advanced Search

The spectrum of pulmonary manifestations associated with mixed connective tissue disease ranges from pulmonary hypertension and interstitial lung disease to pleural effusions, alveolar hemorrhage, and complications from the thromboembolic disease. Interstitial lung disease in mixed connective tissue disease is a frequently occurring entity, although in most cases it tends to be self-limited or slowly progressive. Despite this, a significant percentage of patients may present a progressive fibrosing phenotype, thus posing a great challenge regarding its therapeutic approach, given the scarcity of clinical studies that compare the efficacy of immunosuppressants available to date. Due to this, many recommendations are extrapolated from other diseases with similar characteristics such as systemic sclerosis and systemic lupus erythematosus. That is why it is proposed to carry out an advanced search of the literature in order to clarify its clinical, radiological, and therapeutic characteristics to achieve its evaluation from a holistic point of view.

Clinical perspective and practices on pleural effusions in chronic systemic inflammatory diseases

Systemic inflammatory diseases are a heterogeneous family of autoimmune chronic inflammatory disorders that affect multiple systems within the human body. Connective tissue disease (CTD) is a large group within this family characterised by immune-mediated inflammation of the connective tissue. This group of disorders are often associated with pleural manifestations. CTD-induced pleuritis exhibits a wide variety of symptoms and signs including exudative pleural effusions and chest pain. Accurate estimation of prevalence for CTD-related pleuritis is challenging as small effusions are asymptomatic and remain undetected. Rheumatoid arthritis and systemic lupus erythematosus are frequent CTDs and present with pleural pathology in approximately 5–20% and 17–60% of cases, respectively. By contrast, pleural involvement in systemic sclerosis, eosinophilia–myalgia syndrome, mixed connective tissue disease, ankylosing spondylitis, polymyositis and dermatomyositis syndrome is rare. Clinical management depends on the severity of symptoms; however, most effusions resolve spontaneously. In this review we discuss the pathophysiological mechanisms and the clinical considerations of CTD-induced pleuritis.

Chronic inflammatory diseases could cause pleural pathology. Clinical management depends on the severity of symptoms, but most effusions resolve spontaneously.https://bit.ly/333euHb

Clinical and Immunological Profile of Mixed Connective Tissue Disease and a Comparison of Four Diagnostic Criteria

Mixed connective tissue disease (MCTD) was initially described as a chronic immune-mediated disease with overlapping features of systemic lupus erythematosus, scleroderma, and polymyositis. We conducted a cross-sectional study to describe the clinical and immunological profile of patients with MCTD and to compare the four diagnostic criteria, namely, Sharp, Kasukawa, Alarcón-Segovia, and Khan criteria. A total of 291 patients who were admitted from June 2007 to June 2017 and fulfilled the inclusion criteria were included in the study. A clinical diagnosis of MCTD was made in 111 patients, of whom 103 (92.8%) were women. The mean age at presentation was 39.3 years (SD ± 11.6). The most common organ systems that were involved were musculoskeletal system (95.5%), skin and mucosa (78.4%), and the gastrointestinal and hepatobiliary systems (56%). The maximum sensitivity was for the Kasukawa criteria with a sensitivity of 77.5% (95% CI 68.4-84.6) and specificity of 92.2% (95% CI 87-95.5). The Kahn criteria and Alarcón-Segovia criteria had the maximum specificity; the Alarcón-Segovia criteria had a sensitivity of 69.4% (95% CI 59.8-77.6) and a specificity of 99.4% (95% CI 96.5-99.9), while the Kahn criteria had a sensitivity of 52.3% (95% CI 42.6-61.7) and a specificity of 99.4% (95% CI 96.5-99.9). The sensitivity and specificity of Sharp criteria were 57.7% (95% CI 47.9-66.87) and 90% (95% CI 84.4-93.8), respectively.

Coexistence of Mixed Connective Tissue Disease and Familial Mediterranean Fever in a Japanese Patient

We herein report a Japanese patient with familial Mediterranean fever (FMF) who developed the clinical manifestations of mixed connective tissue disease (MCTD) and Sjögren's syndrome. The patient was a 36-year-old woman presenting with a periodic short-duration (2-3 days) fever and pleural pain. An Mediterranean fever (MEFV) gene analysis detected a complex allele mutation (P369S/R408Q) in exon 3 of the MEFV gene. Serological and clinical data showed the coexistence of MCTD and Sjögren's syndrome. Treatment with colchicine (1.0 mg/day) successfully eliminated febrile attack and pleuritis, leading to the diagnosis of FMF. Four months after the initiation of colchicine treatment, she presented with MCTD-related pulmonary artery hypertension. This is the first report of FMF coexisting with MCTD.

Pathological interpretation of connective tissue disease-associated lung diseases

Connective tissue diseases (CTDs) can affect all compartments of the lungs, including airways, alveoli, interstitium, vessels, and pleura. CTD-associated lung diseases (CTD-LDs) may present as diffuse lung disease or as focal lesions, and there is significant heterogeneity between the individual CTDs in their clinical and pathological manifestations. CTD-LDs may presage the clinical diagnosis a primary CTD, or it may develop in the context of an established CTD diagnosis. CTD-LDs reveal acute, chronic or mixed pattern of lung and pleural manifestations. Histopathological findings of diverse morphological changes can be present in CTD-LDs airway lesions (chronic bronchitis/bronchiolitis, follicular bronchiolitis, etc.), interstitial lung diseases (nonspecific interstitial pneumonia/fibrosis, usual interstitial pneumonia, lymphocytic interstitial pneumonia, diffuse alveolar damage, and organizing pneumonia), pleural changes (acute fibrinous or chronic fibrous pleuritis), and vascular changes (vasculitis, capillaritis, pulmonary hemorrhage, etc.). CTD patients can be exposed to various infectious diseases when taking immunosuppressive drugs. Histopathological patterns of CTD-LDs are generally nonspecific, and other diseases that can cause similar lesions in the lungs must be considered before the diagnosis of CTD-LDs. A multidisciplinary team involving pathologists, clinicians, and radiologists can adequately make a proper diagnosis of CTD-LDs.

Facts and controversies in mixed connective tissue disease

Mixed connective tissue disease (MCTD) is a systemic autoimmune rheumatic disease (SARD) characterised by the combination of clinical manifestations of systemic lupus erythematosus (SLE), cutaneous systemic sclerosis (SSc) and polymyositis-dermatomyositis, in the presence of elevated titers of anti-U1-RNP antibodies. Main symptoms of the disease are polyarthritis, hand oedema, Raynaud's phenomenon, sclerodactyly, myositis and oesophageal hypomobility. Although widely discussed, most authors today accept MCTD as an independent entity. Others, however, suggest that these patients may belong to subgroups or early stages of certain definite connective diseases, such as SLE or SSc, or are, in fact, SARD overlap syndromes.

Pulmonary arterial hypertension, a novelty in idiopathic inflammatory myopathies: insights and first experiences with vasoactive therapy

To characterise the different types of pulmonary hypertension (PH) among idiopathic inflammatory myopathy (IIM). A retrospective case series with assessment of PH by right heart catheterisation, extent of interstitial lung disease (ILD) and outcome of vasoactive therapy.The group of patients with IIM with PH (n=9) showed a median age at PH diagnosis of 62 years (IQR 48–71 years; eight women), seven diagnosed with polymyositis and two with dermatomyositis; median disease duration of 5.7 years and five patients with a positive anti-Jo1 antibody. We found one patient to be classified in PH WHO group 2 (left heart disease), five patients in WHO group 3 (lung disease) and three patients in WHO group 1 (pulmonary arterial hypertension (PAH)). During median observed follow-up of 24 months, mortality for the total group was 44%. Surprisingly, we found a relevant group (33%) of patients with IIM who suffered from non-ILD-PH, which reflects the presence of PAH phenotype. This result should lead to more awareness among treating physicians that complaints of dyspnoea among patient with IIM could be related to PAH and not only ILD. The role of vasoactive therapy remains to be defined in patients with IIM suffering from PAH or PH-ILD.

Posterior reversible encephalopathy syndrome in a patient with mixed connective tissue disease: a case report

Background

Posterior reversible encephalopathy is a syndrome highly associated with hypertension and cytotoxic therapy. The syndrome typically presents with headache, visual abnormality, seizures and characteristic vasogenic edema on magnetic resonance imaging. The entity warrants a prompt diagnosis to avoid deteriorating consequences.

Case presentation

In this report, we describe a 15-year-old Iranian boy who was diagnosed with mixed connective tissue disease, and cyclophosphamide pulse therapy was administered. Three days after the second pulse of cyclophosphamide, when he was receiving prednisolone and hydroxycholoroquine, our patient developed generalized tonic-clonic seizures. Magnetic resonance imaging findings showed high signal intensities in the posterior areas of his brain. After 8 days, the brain magnetic resonance imaging abnormalities were resolved following the control of his blood pressure and antiepileptic treatment. These observations have been indicative of posterior reversible encephalopathy syndrome. Nevertheless, our patient developed uncontrollable respiratory distress and eventually died.

Conclusions

To the best of our knowledge, this case is the first report of posterior reversible encephalopathy syndrome in a patient with mixed connective tissue disease. As the patient developed posterior reversible encephalopathy syndrome 3 days after cyclophosphamide pulse therapy to reduce the disease activity, it is hard to accurately determine whether posterior reversible encephalopathy syndrome in this case is a complication of cyclophosphamide or a condition that resulted from the mixed connective tissue disease flare-up.

Histopathology of lung disease in the connective tissue diseases

The pathologic correlates of interstitial lung disease (ILD) secondary to connective tissue disease (CTD) comprise a diverse group of histologic patterns. Lung biopsies in patients with CTD-associated ILD tend to demonstrate simultaneous involvement of multiple anatomic compartments of the lung. Certain histologic patterns tend to predominate in each defined CTD, and it is possible in many cases to confirm connective tissue-associated lung disease and guide patient management using surgical lung biopsy. This article will cover the pulmonary pathologies seen in rheumatoid arthritis, systemic sclerosis, myositis, systemic lupus erythematosus, Sjögren syndrome, and mixed CTD.

Pulmonary manifestations of Sjögren syndrome, systemic lupus erythematosus, and mixed connective tissue disease

Interstitial lung disease is a common and often life-threatening manifestation of different connective tissue disorders, often affecting its overall prognosis. Systemic lupus erythematosus, Sjögren syndrome, and mixed connective tissue disease, although all unique diseases, can have lung manifestations as an important part of these conditions. This article reviews the different pulmonary manifestations seen in these 3 systemic rheumatologic conditions.

[Lung is also involved in juvenile dermatomyositis]

Juvenile dermatomyositis is the leading cause of chronic idiopathic inflammatory myopathy of auto-immune origin in children. Lung involvement in inflammatory myopathies is well described in adults, involving mostly interstitial lung disease, aspiration pneumonia and alveolar hypoventilation. We propose to describe its specificities in children. Pulmonary involvement may be asymptomatic and therefore must be systematically screened for. In case of clinical or functional respiratory abnormality, a chest computed tomographic (CT) scan is necessary. In children, a decrease of respiratory muscle strength seems common and should be systematically and specifically searched for by non-invasive and reproducible tests (sniff test). Interstitial lung disease usually associates restrictive functional defect, impairment of carbon monoxide diffusion and interstitial lung disease on CT scan. As in adults, the first-line treatment of juvenile dermatomyositis is based on corticosteroids. Corticosteroid resistant forms require corticosteroid bolus or adjuvant immunosuppressive drugs (methotrexate or cyclosporine). There is no consensus in pediatrics for the treatment of diffuse interstitial lung disease. Complications of treatment, including prolonged steroid therapy, are frequent and therefore a careful assessment of the treatments risk-benefit ratio is necessary, especially in growing children.

Clinical course, prognosis, and causes of death in mixed connective tissue disease

OBJECTIVE

To study the survival rate and prognostic indicators of mixed connective tissue disease (MCTD) in a Hungarian population.

METHODS

Two hundred eighty patients with MCTD diagnosed between 1979 and 2011 were followed prospectively. Clinical features, autoantibodies, and mortality data were assessed. Prognostic factors for survival were investigated and survival was calculated from the time of the diagnosis by Kaplan-Meier method.

RESULTS

A total of 22 of 280 patients died: the causes of death were pulmonary arterial hypertension (PAH) in 9 patients, thrombotic thrombocytopenic purpura in 3, infections in 3, and cardiovascular events in 7. The 5, 10, and 15-year survival rates after the diagnosis was established were 98%, 96%, and 88%, respectively. The deceased patients were younger at the diagnosis of MCTD compared to patients who survived (35.5 ± 10.4 vs 41.8 ± 10.7 yrs; p < 0.03), while there was no difference in the duration of the disease (p = 0.835). Our cohort study showed that the presence of cardiovascular events (p < 0.0001), esophageal hypomotility (p = 0.04), serositis (p < 0.001), secondary antiphospholipid syndrome (p = 0.039), and malignancy (p < 0.001) was significantly higher in the deceased patients with MCTD. The presence of anticardiolipin (p = 0.019), anti-β2-glycoprotein I (p = 0.002), and antiendothelial cell antibodies (p = 0.002) increased the risk of mortality.

CONCLUSION

Overall, PAH remained the leading cause of death in patients with MCTD. The prevalence of cardiovascular morbidity and mortality, malignancy, and thrombotic events increased during the disease course of MCTD. The presence of antiphospholipid antibodies raised the risk of mortality.

Pulmonary hypertension in rheumatic diseases: epidemiology and pathogenesis

The focus of this review is to increase awareness of pulmonary arterial hypertension (PAH) in patients with rheumatic diseases. Epidemiology and pathogenesis of PAH in rheumatic diseases is reviewed, with recommendations for early screening and diagnosis and suggestion of possible role of immunosuppressive therapy in treatment for PAH in rheumatic diseases. A MEDLINE search for articles published between January 1970 and June 2012 was conducted using the following keywords: pulmonary hypertension, scleroderma, systemic sclerosis, pulmonary arterial hypertension, connective tissues disease, systemic lupus erythematosus, mixed connective tissue disease, rheumatoid arthritis, Sjogren's syndrome, vasculitis, sarcoidosis, inflammatory myopathies, dermatomyositis, ankylosing spondylitis, spondyloarthropathies, diagnosis and treatment. Pathogenesis and disease burden of PAH in rheumatic diseases was highlighted, with emphasis on early consideration and workup of PAH. Screening recommendations and treatment were touched upon. PAH is most commonly seen in systemic sclerosis and may be seen in isolation or in association with interstitial lung disease. Several pathophysiologic processes have been identified including an obliterative vasculopathy, veno-occlusive disease, formation of microthrombi and pulmonary fibrosis. PAH in systemic lupus erythematosus is associated with higher prevalence of antiphospholipid and anticardiolipin antibodies and the presence of Raynaud's phenomenon. Endothelial proliferation with vascular remodeling, abnormal coagulation with thrombus formation and immune-mediated vasculopathy are the postulated mechanisms. Improvement with immunosuppressive medications has been reported. Pulmonary fibrosis, extrinsic compression of pulmonary arteries and granulomatous vasculitis have been reported in patients with sarcoidosis. Intimal and medial hyperplasia with luminal narrowing has been observed in Sjogren's syndrome, mixed connective tissue disease and inflammatory myopathies. Pulmonary arterial hypertension (PAH) associated with rheumatic diseases carries a particularly grim prognosis with faster progression of disease and poor response to therapy. Though largely associated with systemic sclerosis, it is being increasingly recognized in other rheumatic diseases. An underlying inflammatory component may explain the poor response to therapy in patients with rheumatic diseases and is a rationale for consideration of immunosuppressive therapy in conjunction with vasodilator therapy in treatment for PAH. Further studies identifying pathogenetic pathways and possible targets of therapy, especially the role of immunomodulatory medications, are warranted.

Diffuse and interstitial lung disease and childhood rheumatologic disorders

PURPOSE OF REVIEW

Advances in genetics and clinical diagnostics, along with recently described clinical entities and refined classification schemes, have improved our understanding of diffuse and interstitial lung diseases in children. This review presents recent updates in these disorders in the context of systemic inflammatory conditions.

RECENT FINDINGS

Classification of childhood diffuse lung disease (DLD) using adult paradigms is not useful. Distinct clinical-pathologic entities exist in children. Infants are more likely to present with genetic and developmental disorders, and older children with inflammatory and immune-mediated conditions. A combination of clinical evaluation, high-resolution computed tomography scanning, pulmonary function testing and serology, with bronchoscopy and surgical lung biopsy in selected cases, is most useful in the evaluation of DLD in the context of rheumatologic conditions. Common causes of DLD, such as infection, especially in the setting of immunodeficiency, must be ruled out. Optimal therapy for specific disorders will require careful analysis of data from national registries. Emerging use of biomarkers and high-throughput molecular analysis will yield novel insight into these disorders.

SUMMARY

In the setting of known or suspected rheumatologic disorders, diagnosis and management of DLD are challenging, and require close collaboration among rheumatologists, pulmonologists, and other specialists.

Pulmonary manifestations of scleroderma and mixed connective tissue disease

Pulmonary manifestations are common in connective tissue diseases, and are associated with significant morbidity and mortality in this patient population. Systemic sclerosis (SSc) and mixed connective tissue disease (MCTD) are clinical entities for which the detection of lung involvement is essential to improve patient care and outcomes. This article discusses the pathogenesis, clinical presentation, and evaluation of the patient with pulmonary disease related to SSc and MCTD, with an emphasis on interstitial lung disease and pulmonary hypertension.

Case history of mixed connective tissue disease

The literary review on mixed connective tissue disease is given according to modern international data. The case history of this pathology is described. The case has been observed in the rheumatological department of the Federal Research Clinical Center FMBA of Russia.

Endothelial cell markers reflecting endothelial cell dysfunction in patients with mixed connective tissue disease

INTRODUCTION

The aim of the present study was to investigate the association between cardiovascular risk factors and endothelial dysfunction in patients with mixed connective tissue disease (MCTD) and to determine which biomarkers are associated with atherosclerotic complications, such as cardiovascular disease.

METHODS

Fifty MCTD patients and 38 healthy age-matched and sex-matched controls were enrolled in this study. In order to describe endothelial dysfunction, we assessed flow-mediated dilation (FMD), nitrate-mediated dilation (NMD) and carotid artery intima-media thickness (IMT). We investigated FMD of the brachial artery after reactive hyperemia and NMD after sublingual nitroglycerin administration, while the IMT of the common carotid artery was determined by ultrasound. Anti-U1 ribonucleoprotein (anti-U1RNP) antibodies, anti-cardiolipin (anti-CL) antibodies, anti-endothelial cell antibody (AECA) and endothelial cell markers, such as soluble thrombomodulin (TM) and von Willebrand factor antigen (vWFAg), were assessed.

RESULTS

The endothelium-dependent vasodilation (FMD) was significantly impaired in patients with MCTD, as compared with controls (%FMD: 4.7+/-4.2% vs. 8.7+/-5.0%; P<0.001), while the percentage NMD did not differ (%NMD: 14.3+/-6.6% vs. 17.1+/-6.7%; P=0.073). Mean carotid IMT values were higher in patients than in controls (IMT: MCTD, 0.64+/-0.13 mm vs. controls, 0.53+/-0.14 mm; P<0.001). FMD negatively correlated with disease duration, the levels of apolipoprotein A1, the paraoxonase-1 activity, and systolic blood pressure in MCTD patients. The percentage FMD was significantly lower in MCTD patients with cardiovascular diseases (CVD), than in those without CVD (%FMD: 3.5+/-2.9 vs. 5.8+/-4.8, P<0.0002), while percentage NMD did not differ between patients with and without CVDs. Serum levels of autoantibodies (anti-U1RNP, AECA and anti-CL) were significantly higher in MCTD patients and differed between MCTD patients with and without CVD. Endothelial cell markers such as soluble TM (12.2+/-8.1 ng/ml vs. 3.2+/-1.3 ng/ml; P<0.001) and vWFAg (224.1+/-115% vs. 89.4+/-27.1%, P<0.001) were the highest in MCTD patients with CVD.

CONCLUSIONS

FMD is a reliable sensitive marker of endothelial cell dysfunction in MCTD. Beside the traditional risk factors, anti-U1RNP, AECA and anti-CL antibodies may be important not only in the pathogenesis of MCTD but in the induction of endothelial cell activation, and may play crucial roles in the development of early atherosclerosis in MCTD.

Pulmonary hypertension in polymyositis-dermatomyositis: clinical and hemodynamic characteristics and response to vasoactive therapy

The increased incidence of pulmonary hypertension and its association with decreased survival is well-recognised in patients with systemic sclerosis. This association is not widely appreciated in patients with polymyositis-dermatomyositis. We report clinical and hemodynamic characteristics and response to vasoactive therapy in three patients with polymyositis-dermatomyositis and pulmonary hypertension and discuss them in light of the available literature.

Sensorineural Hearing Loss in Patients with Mixed Connective Tissue Disease: Immunological Markers and Cytokine Levels

Objective.

To investigate the frequency of sensorineural hearing loss (SNHL) in patients with mixed connective tissue disease (MCTD).

Methods.

The study population consisted of 71 patients with MCTD (69 female; 2 male), with a mean age of 57.1 ± 7.9 years and a mean disease duration of 14.5 ± 8.0 years. All patients underwent audiological evaluation that included pure tone and speech audiometry. In addition, the systemic manifestations of the disease and drug therapy were recorded. All patients were tested for presence of autoantibodies. Fifty-one age-matched healthy subjects served as controls.

Results.

SNHL was found in 33 (46.4%) of the 71 patients with MCTD. There was no correlation between SNHL and age and disease duration. An association was found between Raynaud’s phenomenon (p < 0.03), secondary antiphospholipid syndrome (APS) (p < 0.05), and SNHL. MCTD patients with SNHL had higher serum levels of anti-U1RNP (p < 0.05), antiendothelial cell antibodies (p < 0.001), and IgG type anticardiolipin antibodies (p < 0.0001) than patients without SNHL. Serum levels of interferon-γ and tumor necrosis factor-α were increased in MCTD patients with SNHL compared to patients without SNHL. The absolute number of natural (CD4+CD25highFoxP+) regulatory T cells (Treg) was lower compared to patients without SNHL.

Conclusion.

In MCTD, SNHL is a specific organ manifestation and appears frequently. We have found that pathogenic autoantibodies, decreased levels of regulatory T cells, and overexpression of proinflammatory cytokines may play a role in the pathogenesis of immune mediated inner ear disorders in MCTD.

Mixed connective tissue disease: what is behind the curtain?

Although there is still an emotional debate over the existence of mixed connective tissue disease, the evidence from animal models suggests that anti-U1RNP antibodies, similar to other autoantibodies in other connective tissue diseases (such as antisynthetase, anticentromere, and antitopoisomerase), play a pathophysiological role in this disease. Despite an antiendothelial effect of anti-U1RNP antibodies, which is reminiscent of anticentromere antibodies, patients with high-titer autoantibodies to U1RNP in the absence of anti-Sm antibodies do not usually have or develop typical systemic sclerosis. Instead, their severe Raynaud's syndrome is commonly accompanied by arthritis, which can be erosive, and by swollen/puffy hands and myositis. Pulmonary arterial hypertension is the major life-threatening complication in these patients and regular screening for this condition is essential.

Atteintes pulmonaires des polymyosites et dermatopolymyosites

Polymyositis is characterised by an inflammatory reaction in skeletal muscle with a variable degree of muscular weakness and associated with skin lesions in the case of dermatomyositis. Involvement of the muscles of deglutition and the diaphragm may lead to inhalation pneumonia and acute or chronic respiratory failure, often hypercapnic. The other respiratory manifestations are diffuse interstitial pneumonitis (DIP), usually non-specific, and very occasionally pulmonary arterial hypertension. The development of DIP during polymyositis is a grave prognostic factor, respiratory involvement being one of the main causes of morbidity and mortality. The onset of DIP is acute in between 30 and 47% of cases. Anti-synthetase antibodies (particularly anti-JO-1) are positive in about 75% of cases. Treatment is usually with a combination of immunosuppressants and corticosteroids without any immunosuppressants therapy having shown a superiority.

Clinical and Immunoserological Characteristics of Mixed Connective Tissue Disease Associated with Pulmonary Arterial Hypertension

We investigated the clinical characteristics and immunoserological alterations in patients with mixed connective tissue disease (MCTD) associated with pulmonary arterial hypertension (PAH). Anti-U1RNP autoantibodies, anti-endothelial cell antibodies (AECA) and serum thrombomodulin (TM) as well as von Willebrand factor antigen (vWFAg) concentrations were measured in 25 patients with MCTD associated with PAH and in 154 MCTD patients without PAH. The results showed that the probability of survival was lower in MCTD patients with PAH than in the 154 MCTD-non-PAH patients (5-year survival rate in MCTD with PAH: 73%, versus 96% in MCTD-non-PAH; P < 0.01). AECA were more frequently present in the sera of MCTD patients with PAH than in MCTD-non-PAH (P < 0.001). Serum TM and vWFAg levels were higher in MCTD-PAH patients than in MCTD-non-PAH patients (TM: P < 0.001; vWFAg: P < 0.001). Significant correlation was noticed between the quantity of AECA and TM level (r = 0.466) as well as the quantity of AECA and vWFAg level (r = 0.550). In conclusion, our results suggest that in MCTD the presence of AECA and endothelial cell activation may play a role in the development of PAH and in the maintenance of obliterative vascular processes.