The patient was a 55-year-old man who was admitted to hospital with "progressive myalgia and weakness for 4 months, and exacerbated for 1 month". Four months ago, he presented with persistent shoulder girdle myalgia and elevated creatine kinase (CK) at routine physical examination, which fluctuated from 1 271 to 2 963 U/L after discontinuation of statin treatment. Progressive myalgia and weakness worsened seriously to breath-holding and profuse sweating 1 month ago. The patient was post-operative for renal cancer, had previous diabetes mellitus and coronary artery disease medical history, had a stent implanted by percutaneous coronary intervention and was on long-term medication with aspirin, atorvastatin and metoprolol. Neurological examination showed pressure pain in the scapularis and pelvic girdle muscles, and V- grade muscle strength in the proximal extremities. Strongly positive of anti-HMGCR antibody was detected. Muscle magnetic resonance imaging (MRI) T2-weighted image and short time inversion recovery sequences (STIR) showed high signals in the right vastus lateralis and semimembranosus muscles. There was a small amount of myofibrillar degeneration and necrosis, CD4 positive inflammatory cells around the vessels and among myofibrils, MHC-Ⅰ infiltration, and multifocal lamellar deposition of C5b9 in non-necrotic myofibrils of the right quadriceps muscle pathological manifestation. According to the clinical manifestation, imageological change, increased CK, blood specific anti-HMGCR antibody and biopsy pathological immune-mediated evidence, the diagnosis of anti-HMGCR immune-mediated necrotizing myopathy was unequivocal. Methylprednisolone was administrated as 48 mg daily orally, and was reduced to medication discontinuation gradually. The patient's complaint of myalgia and breathlessness completely disappeared after 2 weeks, the weakness relief with no residual clinical symptoms 2 months later. Follow-up to date, there was no myalgia or weakness with slightly increasing CK rechecked. The case was a classical anti-HMGCR-IMNM without swallowing difficulties, joint symptoms, rash, lung symptoms, gastrointestinal symptoms, heart failure and Raynaud's phenomenon. The other clinical characters of the disease included CK as mean levels >10 times of upper limit of normal, active myogenic damage in electromyography, predominant edema and steatosis of gluteus and external rotator groups in T2WI and/or STIR at advanced disease phase except axial muscles. The symptoms may occasionally improve with discontinuation of statins, but glucocorticoids are usually required, and other treatments include a variety of immunosuppressive therapies such as methotrexate, rituximab and intravenous gammaglobulin.
Male ; Humans ; Middle Aged ; Autoantibodies ; Myositis/diagnosis* ; Autoimmune Diseases ; Muscle, Skeletal/pathology* ; Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use* ; Necrosis/pathology* ; Muscular Diseases/drug therapy*

OBJECTIVE: To investigate the clinical and immunological features of cardiac involvement in patients with anti-synthetase syndrome (ASS). METHODS: In the study, 96 patients diagnosed with ASS hospitalized in the Department of Rheumatology and Immunology, Peking University People's Hospital from April 2003 to November 2020 were included. The patients were divided into two groups according to whether they were accompanied with cardiac involvement. Demographic features, clinical characteristics (Gottron's sign/papules, muscle damage, etc.), comorbidities, laboratory indices (creatine kinase, inflammatory indicators, immunoglobulin, complement, lymphocyte subset, autoantibodies, etc.) were collected and the differences between the two groups were analyzed statistically. RESULTS: The prevalence of cardiac involvement in the patients with ASS was 25.0% (24/96). The ASS patients complicated with cardiac involvement presented with elevated cardiac troponin I (cTnI, 75.0%, 18/24), pericardial effusion (33.3%, 8/24), reduction of left ventricular function (33.3%, 8/24) and valves regurgitation (33.3%, 8/24). The age of onset of the patients with cardiac involvement was older than that of the patients without cardiac involvement [(54.58±10.58) years vs. (48.47±13.22) years, P=0.043). Arthritis was observed less frequently in the patients with cardiac involvement than those without cardiac involvement (37.5% vs. 61.1%, P=0.044). In addition, rapidly progressive interstitial lung disease (54.2% vs. 30.6%, P=0.037) was observed more frequently in the patients with cardiac involvement than those without cardiac involvement. As compared with the ASS patients without cardiac involvement, C-reactive protein (CRP) [(13.55 (8.96, 38.35) mg/L vs. 4.60 (1.37, 17.40) mg/L, P=0.001], and lactate dehydrogenase (LDH) [408.0 (255.0, 587.0) U/L vs. 259.5 (189.8, 393.8) U/L, P=0.007] were significantly higher in the patients with cardiac involvement. Anti-Ro-52 antibody was detected more commonly in the ASS patients with cardiac involvement compared with the patients without cardiac involvement (91.7% vs. 69.4%, P=0.029). No significant differences were found in the comorbidities, alanine transaminase (ALT), aspartate transaminase (AST), creatine kinase (CK), erythrocyte sedimentation rate (ESR), ferritin (Fer), immunoglobulin G (IgG), complement 3 (C3), complement 4 (C4), lymphocyte subset between the two groups. CONCLUSION Cardiac involvement is common in ASS, mainly manifested as myocardial damage. It is necessary to be aware of cardiac complications in patients with elevated CRP, elevated LDH and positive anti-Ro-52 antibody.
Adult ; Aged ; Antibodies, Antinuclear ; Autoantibodies ; Blood Sedimentation ; C-Reactive Protein ; Heart Diseases/complications* ; Humans ; Immunoglobulin G ; L-Lactate Dehydrogenase ; Middle Aged ; Myositis/diagnosis*

Connective tissue disease (CTD) is a collection of disorders characterized by various signs and symptoms such as circulation of autoantibodies in the entire system causing damage to internal organs. Interstitial lung disease (ILD) which is associated with CTD is referred to as CTD-ILD. Patients diagnosed with ILD should be thoroughly examined for the co-occurrence of CTD, since the treatment procedures and prognosis of CTD-ILD are vary from those of idiopathic interstitial pneumonia. The representative types of CTD which may accompany ILD include rheumatoid arthritis, systemic sclerosis (SSc), Sjögren's syndrome, mixed CTD, idiopathic inflammatory myopathies, and systemic lupus erythematous. Of these, ILD most frequently co-exists with SSc. If an ILD is observed in the chest, high resolution computed tomography and specific diagnostic criteria for any type of CTD are met, then a diagnosis of CTD-ILD is made. It is challenging to conduct a properly designed randomized study on CTD-ILD, due to low incidence. Therefore, CTD-ILD treatment approach is yet to been established in absence of randomized controlled clinical trials, with the exception of SSc-ILD. When a patient is presented with acute CTD-ILD or if symptoms occur due to progression of the disease, steroid and immunosuppressive therapy are generally considered.
Arthritis, Rheumatoid ; Asian Continental Ancestry Group ; Autoantibodies ; Connective Tissue Diseases ; Connective Tissue ; Diagnosis ; Disease Management ; Guidelines as Topic ; Humans ; Idiopathic Interstitial Pneumonias ; Incidence ; Lung ; Lung Diseases, Interstitial ; Myositis ; Prognosis ; Scleroderma, Systemic ; Thorax

Proliferative myositis is a rare, benign, probably pseudosarcomatous fibroblastic proliferation that typically presents as a rapidly growing soft tissue mass. Its relative rarity, fast growth rate, and unique histopathologic findings may lead to misdiagnosis as a malignant lesion and unnecessary radical surgical excision. A 57-year-old female presented with a non-tender, well-defined, indurated, solitary, hard papule on the median sulcus of the tongue for 2 weeks. Histologic examination revealed numerous fibroblastic or myofibroblastic spindle cells and large ganglion-like cells infiltrating between and around the muscle fascicles. Immunohistochemical staining showed positivity for vimentin, smooth muscle actin, and CD68 and negativity for S-100. Based on these characteristic clinical findings and histopathologic features, the patient was diagnosed with proliferative myositis. Here, we report a rare case of proliferative myositis on the tongue and recommend considering proliferative myositis in the differential diagnosis when a physician encounters a rapidly grown soft tissue mass.
Actins ; Diagnosis, Differential ; Diagnostic Errors ; Female ; Fibroblasts ; Humans ; Middle Aged ; Muscle, Smooth ; Myofibroblasts ; Myositis* ; Tongue* ; Vimentin

Idiopathic inflammatory myopathies (IIM) are a heterogeneous group of autoimmune muscle diseases with systemic involvement. Patients with IIM present with varying degrees of muscle disease, cutaneous manifestations, and internal organ involvement. The diagnosis and classification of IIM is based primarily on the classification system composed of clinical features, laboratory value and muscle biopsy. In addition, the identification and characterization of myositis-related autoantibodies can help diagnosis and classification. Recently, many studies have also demonstrated that the physician can define the clinical syndromes, establish treatment strategy and predict outcomes based on the patients' myositis-specific autoantibodies (MSA) and myositis-associated antibodies (MAA) profiles. MSAs are found exclusively in IIMs and facilitate the identification of subsets of patients with relatively homogeneous clinical features. MAAs are frequently found in association with other MSA; however, they may also be detected in various connective diseases.
Antibodies ; Antibodies, Antinuclear ; Autoantibodies ; Biopsy ; Classification ; Dermatomyositis ; Diagnosis ; Humans ; Myositis ; Polymyositis

BACKGROUND: Influenza-associated myositis (IAM) is a rare and poorly recognized complication of influenza infection in children, and is characterized by acute onset of severe pain in the lower extremities and a refusal to ambulate walk. We sought to understand the association between IAM and influenza B infection and to investigate its clinical and laboratory characteristics in affected children. METHODS: Influenza B-associated myositis (IBAM) cases diagnosed in the pediatrics department of Wonkwang University Hospital from January 2010 and March 2016 were analyzed retrospectively. RESULTS: Medical records of affected children were examined, and clinical characteristics and laboratory findings were recorded. Of the 536 children diagnosed with influenza B infection, 47 children complained of bilateral calf pain with or without gait disturbance. All children exhibited elevated serum aspartate aminotransferase (AST) level. The median serum creatine kinase (CK) and lactate dehydrogenase (LDH) levels, reportedly elevated in myositis, were 2,597 IU/L and 678 IU/L, respectively. While the immunofluorescence test results were negative for some patients, the polymerase chain reaction test results indicated influenza B infection in all 47 children. At the time of hospital discharge, the patients' symptoms had resolved, and their CK levels had improved. CONCLUSION: IBAM was generally benign and short, and although the blood AST, CK, and LDH levels were markedly high, the erythrocyte sedimentation rate and C-reactive protein levels were normal. Further, the duration of IBAM symptoms correlated with the duration of fever. The IBAM-associated clinical and laboratory findings are highly characteristic and may allow its rapid diagnosis during the influenza season.
Aspartate Aminotransferases ; Blood Sedimentation ; C-Reactive Protein ; Child ; Creatine Kinase ; Diagnosis ; Fever ; Fluorescent Antibody Technique ; Gait ; Humans ; Influenza B virus ; Influenza, Human ; L-Lactate Dehydrogenase ; Lower Extremity ; Medical Records ; Myalgia ; Myositis ; Pediatrics ; Polymerase Chain Reaction ; Retrospective Studies ; Seasons

Fibrodysplasia ossificans progressiva (FOP) is a rare genetic disease that is characterized by the formation of heterotopic bone tissues in soft tissues, such as skeletal muscle, ligament, and tendon. It is difficult to remove such heterotopic bones via internal medicine or invasive procedures. The identification of activin A receptor, type I (ACVR1)/ALK2 gene mutations associated with FOP has allowed the genetic diagnosis of FOP. The ACVR1/ALK2 gene encodes the ALK2 protein, which is a transmembrane kinase receptor in the transforming growth factor-β family. The relevant mutations activate intracellular signaling in vitro and induce heterotopic bone formation in vivo. Activin A is a potential ligand that activates mutant ALK2 but not wild-type ALK2. Various types of small chemical and biological inhibitors of ALK2 signaling have been developed to establish treatments for FOP. Some of these are in clinical trials in patients with FOP.
Activins ; Bone and Bones ; Diagnosis ; Humans ; In Vitro Techniques ; Internal Medicine ; Ligaments ; Muscle, Skeletal ; Myositis Ossificans* ; Osteogenesis ; Phosphotransferases ; Tendons ; Transforming Growth Factor beta

Benign acute childhood myositis (BACM) is a rare transient condition that occurs in children during the early convalescent phase of a viral upper respiratory infection. BACM is self-limiting and characterized by sudden-onset bilateral calf pain that leads to difficulty in walking. We report a case of a 5-year-old boy with BACM who presented with acute-onset bilateral calf pain after a resolved episode of viral pharyngitis and subsequently refused to walk. With conservative treatment, the patient recovered completely after approximately 1 week. Although perplexing and challenging for clinicians unfamiliar with BACM, awareness of this rare clinical condition is essential to preventing unnecessary investigations and reassuring the patient and parents of its excellent prognosis.
Child ; Child, Preschool ; Diagnosis, Differential ; Humans ; Male ; Mobility Limitation ; Myositis* ; Parents ; Pharyngitis* ; Prognosis ; Respiratory Tract Infections ; Walking

PURPOSE: We report a case of idiopathic orbital myositis with sudden onset of unilateral visual loss and hypertrophy of the lateral rectus muscle at the apex of the orbit that was diagnosed using orbital biopsy and treated with intravenous corticosteroids. CASE SUMMARY: We examined a 20-year-old woman who complained of decreased visual acuity and binocular diplopia for 2 weeks. She showed 40-prism diopter left esotropia at the primary position. Her visual acuity with eyeglasses was 0.7 and 0.2 in the right and left eyes, respectively. Brain magnetic resonance imaging (MRI) revealed a round mass on the left lateral rectus muscle at the apex of the orbit with optic nerve compression. We planned orbital biopsy to exclude orbital lymphoma and other biopsy-requiring diseases. After 3 weeks, the visual acuity of her left eye decreased to 0.02. Repeated MRI revealed enlargement of all extraocular muscles on the left orbit. With biopsy showing several lymphocytes infiltrating muscle fibers, we made a diagnosis of idiopathic orbital myositis. Intravenous injection of corticosteroids was administered during hospitalization. After 2 weeks of corticosteroid therapy, the visual acuity of her left eye was improved to 0.63, the esotropia disappeared, and the enlargement of the left lateral rectus muscle was improved on orbital MRI. CONCLUSIONS: For non-specific idiopathic orbital myositis located at the apex of the orbit and enlargement of the extraocular muscle in a short period with decreased visual acuity, administration of intravenous injection of corticosteroids before orbital biopsy could help restore vision.
Adrenal Cortex Hormones ; Biopsy ; Brain ; Diagnosis* ; Diplopia ; Esotropia ; Eyeglasses ; Female ; Hospitalization ; Humans ; Hypertrophy ; Injections, Intravenous ; Lymphocytes ; Lymphoma ; Magnetic Resonance Imaging ; Muscles ; Optic Nerve ; Orbit* ; Orbital Myositis* ; Telescopes ; Visual Acuity ; Young Adult

Behçet's disease (BD) is a systemic vasculitis commonly accompanied by recurrent mucosal ulceration and other systemic manifestations, but rarely by myositis. Focal eosinophilic myositis is the most limited idiopathic eosinophilic myopathy characterized by peripheral blood eosinophilia and/or eosinophilic muscle infiltration. Clinical manifestations include myalgia, muscle weakness, and cutaneous lesions, such as subcutaneous induration and erythema. Given that BD can mimic deep vein thrombosis or pseudotumor, muscle biopsy should be performed to enhance the accuracy of diagnosis. Microscopic examination reveals extensive infiltration of eosinophils and mononuclear cells into muscle, myofiber necrosis, and regeneration. To the best of our knowledge, there have not been any published reports on MEDLINE regarding focal eosinophilic myositis associated with BD. Here, we presented a case of focal eosinophilic myositis associated with intestinal BD in a 23-year-old man who suffered from a large ulcer in the terminal ileum.
Biopsy ; Diagnosis ; Eosinophilia ; Eosinophils* ; Erythema ; Humans ; Ileum ; Muscle Weakness ; Muscular Diseases ; Myalgia ; Myositis* ; Necrosis ; Regeneration ; Systemic Vasculitis ; Ulcer ; Venous Thrombosis ; Young Adult