Les manifestations pulmonaires du syndrome des antisynthétases

Longitudinal Study of Patients with Connective Tissue Disease-Interstitial Lung Disease and Response to Mycophenolate Mofetil and Rituximab

Background/Objective: To investigate the effect of mycophenolate mofetil (MMF) and rituximab (RTX) on pulmonary function test (PFT) results in a mixed cohort of patients with connective tissue disease-associated interstitial lung disease (CTD-ILD), longitudinally followed up for 1 year in a single academic center. Methods: Patients with CTD-ILD were identified in electronic medical records from 1 January 2009 to 30 April 2019. Prescribed MMF and RTX doses, dosage changes, and therapy plans were analyzed individually with improvement in PFT outcomes determined using multivariable linear regression models during 12-month follow-up. Results: Forty-seven patients with CTD-ILD, treated with MMF, RTX, or both, were included. Patients on combined MMF and RTX had worse PFT outcomes at baseline compared with patients on monotherapy. Substantial improvement was observed among all PFT outcomes from baseline to 12 months, regardless of medication dosage or therapy plans. The diffusing capacity of the lungs for carbon monoxide (DLCO) worsened by an average of 7.21 mL/(min*mmHg) (95% CI, 4.08-10.33; p < 0.001) among patients on RTX compared to combined therapy. Patients on higher doses of MMF at baseline experienced an average increase of 0.93 (95% CI, 0.04-1.82) units in DLCO from baseline to 6 months (p = 0.04) and a 2.79% (95% CI, 0.61-4.97%) increase in DLCO from 6 to 12 months (p = 0.02) within patients on concurrent RTX at 6-month follow-up. Conclusions: The treatment of CTD-ILD with MMF and/or RTX was associated with overall improvement in PFT outcomes. Combined therapy resulted in significant improvements in DLCO compared with monotherapy. Higher doses of MMF also provided greater improvements in DLCO.

Diffuse Interstitial Lung Disease Revealing Antisynthetase Syndrome

Interstitial lung disease (ILD) is a frequent manifestation of connective tissue diseases. They may be revelatory of the disease or occur during follow-up. Antisynthetase syndrome (ASS) is a complex and heterogeneous autoimmune disorder. Antisynthetase antibodies, in particular the anti-Jo-1 antibody, characterize this syndrome. The occurrence and severity of ILD determine the prognosis, which in turn determines therapeutic management. We report the case of a 53-year-old female patient presenting with ILD, revealing the diagnosis of ASS. The evolution was favorable with bolus corticosteroids associated with cyclophosphamide.

Joint and muscle inflammatory disease: A scoping review of the published evidence

OBJECTIVES

Polyarthritis is commonly reported in idiopathic inflammatory myositis patients, but few studies have focused on the overlap of myositis with rheumatoid arthritis which is a difficult diagnosis in the absence of well-defined diagnostic criteria. The primary objective of this scoping review was to map the field of research to explore the potential diagnoses in patients presenting with both myositis and polyarthritis.

METHODS

Two electronic databases (MEDLINE/PubMed® and Web of Science®) were systematically searched using the terms (myositis OR 'inflammatory idiopathic myopathies') AND (polyarthritis OR 'rheumatoid arthritis') without any publication date limit.

RESULTS

Among individual records, 280 reports met inclusion criteria after full-text review. There was heterogeneity in the definition of overlap myositis as well as the characteristics of rheumatoid arthritis. In many studies, key data were lacking; rheumatoid factor status was reported in 56.8% (n=151), anti-citrullinated proteins antibodies status in 18.8% (n=50), and presence or absence of bone erosions in 45.1% (n=120) of the studies. Thirteen different diagnoses were found to associate myositis with polyarthritis: antisynthetase syndrome (29.6%, n=83), overlap myositis with rheumatoid arthritis (16.1%, n=45), drug-induced myositis (20.0%, n=56), rheumatoid myositis (7.5%, n=21), inclusion body myositis (1.8%, n=5), overlap with connective tissue disease (20.0%, n=56), and others (5.0%, n=14).

CONCLUSION

The spectrum of joint and muscle inflammatory diseases encompasses many diagnoses including primitive and secondary myositis associated with RA or arthritis mimicking RA. This review highlights the need for a consensual definition of OM with RA to better individualise this entity from the numerous differential diagnoses.

[Diffuse infiltrating lung disease secondary to antisynthetase syndrome: a case report]

Les pneumopathies infiltrantes diffuses (PID) constituent une manifestation fréquente des connectivites. Elles peuvent être révélatrices de la maladie ou survenir au cours du suivi. Le syndrome des anti-synthétases (SAS) est une connectivité auto-immune complexe et hétérogène. Des anticorps de type «anti synthétases», en particulier l'anticorps anti-Jo-1 caractérise ce syndrome. Le pronostic du SAS étant conditionné par la survenue d´une PID et de sa sévérité dictant ainsi la prise en charge thérapeutique du SAS. Nous rapportons l´observation d´une patiente âgée de 57 ans se présentant avec un tableau d´une PID aigue fébrile révélant le diagnostic d´un SAS. L´évolution a été favorable sous boli de corticoïdes associés au cyclophosphamide.

Investigating Idiopathic Inflammatory Myopathy; Initial Cross Speciality Experience with Use of the Extended Myositis Antibody Panel

The discovery of unique autoantibodies has informed and altered our approach to the diagnosis and management of the inflammatory myopathies. This study reports the initial clinical experience of use of the Extended Myositis Antibody (EMA) panel in the largest university teaching hospital in Ireland. We conducted a retrospective review of all patients who had serum samples tested for myositis specific antibodies and myositis associated antibodies from April 2014 to March 2015. A positive EMA panel was of significant clinical utility in facilitating decisions on appropriate investigations, and need for onward referral to other physicians. Furthermore, this paper highlights the diversity of possible presentations of idiopathic inflammatory myopathy with subsequent need for multi-speciality involvement, and serves to heighten awareness among clinicians of the diagnostic use of extended myositis antibody testing in these cases.

Secondary myopathy due to systemic diseases

Background

Some systemic diseases also affect the skeletal muscle to various degrees and with different manifestations. This review aimed at summarizing and discussing recent advances concerning the management of muscle disease in systemic diseases.

Method

Literature review by search of MEDLINE, and Current Contents with appropriate search terms.

Results

Secondary muscle disease occurs in infectious disease, endocrine disorders, metabolic disorders, immunological disease, vascular diseases, hematological disorders, and malignancies. Muscle manifestations in these categories include pathogen‐caused myositis, muscle infarction, rhabdomyolysis, myasthenia, immune‐mediated myositis, necrotising myopathy, or vasculitis‐associated myopathy. Muscle affection may concern only a single muscle, a group of muscles, or the entire musculature. Severity of muscle affection may be transient or permanent, may be a minor part of or may dominate the clinical picture, or may be mild or severe, requiring invasive measures including artificial ventilation if the respiratory muscles are additionally involved. Diagnostic work‐up is similar to that of primary myopathies by application of non‐invasive and invasive techniques. Treatment of muscle involvement in systemic diseases is based on elimination of the underlying cause and supportive measures. The prognosis is usually fair if the causative disorder is effectively treatable but can be fatal in single cases if the entire musculature including the respiratory muscles is involved, in case of infection, or in case of severe rhabdomyolysis.

Conclusion

Secondary muscle manifestations of systemic diseases must be addressed and appropriately managed. Prognosis of secondary muscle disease in systemic diseases is usually fair if the underlying condition is accessible to treatment.

Severe respiratory failure as a presenting feature of an interstitial lung disease associated with anti-synthetase syndrome (ASS)

Anti-synthetase syndrome (ASS) is defined as a heterogeneous connective tissue disorder characterized by the association of an interstitial lung disease (ILD) with or without inflammatory myositis with the presence of anti-aminoacyl-tRNA-synthetase antibodies. ILD is one of the major extra-muscular manifestations of polymyositis and dermatomyositis. We report a case of a patient with dyspnea, cough, and intermittent fever as well as ILD associated ASS in the absence of muscular involvement. This patient was admitted to the emergency department with severe respiratory failure requiring non-invasive ventilation. Our patient's case demonstrates that the diagnosis of ASS may not be obvious. However, its diagnosis leads to appropriate and potentially life-saving treatment.