Electrocardiographic changes in dermatomyositis and polymyositis / Alterações eletrocardiográficas em dermatomiosite e polimiosite

ABSTRACT Introduction: Cardiac involvement is frequent in inflammatory myopathies. Electrocardiogram (ECG) may show evidence of this involvement and its changes should be well-known and described. Objectives: Due to the lack of studies in the literature, we conducted an analysis of the ECG findings in patients with dermatomyositis (DM) and polymyositis (PM), comparing them with a control group. Methods: This cross-sectional study compared the ECG of 86 individuals with no rheumatic disorders (controls) with 112 patients (78 DM and 34 PM), during 2010 to 2013. The ECG findings between DM and PM were also compared. Results: Demographic characteristics, comorbidities and ECG abnormalities were similar between controls and patients (p > 0.05), except for a higher frequency of left ventricular hypertrophy (LVH) in patients (10.7% vs. 1.2%, p = 0.008). Demographic characteristics, comorbidities, clinical and laboratory manifestations, were also similar between the groups PM and DM, except for the presence of cutaneous lesions only in DM. One third of the patients had ECG abnormalities, which were more prevalent in PM than DM (50% vs. 24.4%, p = 0.008). LVH, left atrial enlargement, rhythm and conduction abnormalities were more frequent in PM than DM (p < 0.05 for all), especially the left anterior fascicular block. Conclusions: We showed distinct ECG changes between DM and PM and a higher frequency of LVH in patients compared to controls. Investigation of cardiac involvement should be considered even in asymptomatic patients, especially PM. Further studies are necessary in order to determine the correlation of ECG findings with other complementary tests, clinical manifestations, disease activity and progression to other cardiac diseases.

RESUMO Introdução: Acometimento cardíaco nas miopatias inflamatórias é frequente. Eletrocardiograma (ECG) pode mostrar indícios desse acometimento e suas alterações devem ser bem conhecidas e descritas. Objetivos: Devido à escassez de trabalhos na literatura, analisamos as alterações de ECG em pacientes com dermatomiosite (DM) e polimiosite (PM) e as comparamos com um grupo controle. Métodos: Este estudo transversal comparou ECGs de 86 indivíduos sem doenças reumatológicas (controles) com 112 pacientes (78 DM e 34 PM), de 2010 a 2013. Também comparamos os ECGs entre DM e PM. Resultados: Características demográficas, comorbidades e alterações de ECG foram semelhantes entre controles e pacientes (p > 0,05), exceto pela maior frequência de sobrecarga de ventrículo esquerdo (SVE) nos pacientes (10,7% vs. 1,2%; p = 0,008). Características demográficas, comorbidades, manifestações clínicas e laboratoriais também foram semelhantes entre os grupos PM e DM, exceto por lesões cutâneas apenas em pacientes com DM. Um terço dos pacientes apresentou alterações de ECG, que foram mais prevalentes em PM do que em DM (50% vs. 24,4%, p = 0,008). Sobrecarga de câmaras esquerdas (SCE), distúrbios do ritmo e da condução foram mais encontrados em PM do que em DM (p < 0,05 para todos), sobretudo o bloqueio divisional do ramo anterossuperior. Conclusões: Encontramos alterações distintas de ECG entre PM e DM e frequência aumentada de SVE em pacientes quando comparados com controles. Investigação do acometimento cardíaco nessas doenças deve ser considerada mesmo em pacientes assintomáticos, especialmente em se tratando de PM. Mais estudos são necessários para correlacionar os achados de ECG com outros exames complementares, manifestações clínicas, atividade das miopatias e evolução para outras doenças cardíacas.

Compartment Syndrome followed by Inflammatory Myositis in a Patient with Urethral Cancer / 대한내과학회지

Inflammatory myositis is a heterogeneous group of rare diseases characterized by inflammation of the skeletal muscle. The association between cancer and inflammatory myositis is well established, with most cancer-associated myopathies diagnosed within 2 years of initial diagnosis. However, despite this strong association, inflammatory myositis as a paraneoplastic syndrome of urethral cancer has not been reported in Korea. Furthermore, compartment syndrome in the context of inflammatory myositis is extremely rare. A 69 year-old woman presented with paresthesia and painful swelling of the right lower extremity 2 months after diagnosis with urethral cancer, which was treated by chemoradiotherapy. Painful numbness was particularly severe when extending the knee, leading to a preliminary diagnosis of myositis with compartment syndrome, which was confirmed by magnetic resonance imaging. After fascia resection, the patient was treated with high dose steroid and immunoglobulin therapy. Here, we report a case of compartment syndrome followed by inflammatory myositis in a patient with urethral cancer.

Rituximab Treatment for the Patients with Refractory Inflammatory Myopathy

OBJECTIVE: To assess the efficacy and safety of rituximab (RTX) on disease activity and muscle strength in patients with inflammatory myopathies refractory to conventional therapy. METHODS: Four inflammatory myopathy patients who had been refractory to glucocorticoids, one or more immunosuppressive therapies and intravenous immunoglobulin were treated on an open-label basis. Each patient received two 500 mg doses of RTX 2 weeks apart in one cycle. In one patient who did not respond after the first cycle of RTX, the infusion schedule was modified by the physician. We measured muscle enzyme including CPK, LDH and assessed muscle strength individually to evaluate RTX response. Additionally anti-CD19 antibody was measured. RESULTS: Three patients responded to the first cycle of RTX treatment with improvements in muscle enzyme and muscle strength, and then maintained physical function over the duration of several infusion cycles. In one patient, muscle enzyme did not decrease after the first cycle of RTX, and a high dose glucocorticoid was given. After modifying the treatment schedule with monthly RTX infusion, his muscle enzyme level and muscle strength improved. Anti-CD19 antibody decreased after RTX generally, but responses were variable. Herpes zoster infection occurred in two patients. CONCLUSION: Rituximab may be a therapeutic choice in refractory inflammatory myopathy. However a further trial is needed to confirm the efficacy and prove the safety.

Clinical Characteristics of the Lung Involvement in Korean Patients with Inflammatory Myositis / 대한류마티스학회지

OBJECTIVE: To investigate the clinical manifestation and prognostic factors of interstitial lung disease (ILD) in Korean patients with idiopathic inflammatory myopathies include with polymyositis (PM) and dermatomyositis (DM). METHODS: Clinical and laboratory data of 110 patients with PM/DM in our rheumatology clinic were investigated. Clinical data including history, medication, pulmonary function tests (PFT) findings, radiologic findings, and labaratory findings were obtained from medical records at the first diagnosis of ILD with PM/DM. ILD was diagnosed on the basis of the imaging abnormalities defined above on definite findings of chest X-rays and high resolution computed tomography (HRCT), restrictive changes on PFT with respiratory symptoms. During the course of treatment, we assessed chest radiograph and HRCT findings. RESULTS: Forty-two PM/DM patients (38.2%) developed ILD. Anti-extracellular nuclear antigen (ENA) antibody, anti-Jo-1 antibody and ground glass opacity in HRCT were significantly high in PM-ILD. However honeycoomb appearance (53% : 22%) and fibrosis (41% : 6%) in HRCT were significantly high in DM-ILD. Interest in aspects of prognosis including initial steroid treatment response in HRCT were favorable in PM-ILD. There were statistically significant association between normal level of CPK and usual interstitial pneumonia (UIP) pattern in HRCT in DM-ILD. Such cases had resistance to steroid therapy. Overall interval between steroid and immunosuppressant therapy was significantly shorter in those with DM-ILD. CONCLUSION: The clinical manifestations between PM-ILD and DM-ILD in Korean patients were not significant different from those of other populations. DM-ILD is more refractory to steroid treatment, expecting in poor prognosis compared with PM-ILD. So immediate intensive immunosuppressive therapy should be considered in DM-ILD.