China
Africa
Explore chapters and articles related to this topic
Myositis
Published in Jason Liebowitz, Philip Seo, David Hellmann, Michael Zeide, Clinical Innovation in Rheumatology, 2023
Genetic analysis has revealed a significant association between IBM and haplotypes HLA-DRB1*03:01 and HLA-B*08:01.107–110 This association was verified by a recent large-scale genetic study that identified HLA-DRB1*03:01, 01:01 and 13:01 as risk factors for the disease,111 adding to the evidence supporting an autoimmune pathogenesis of IBM. However, no association was found with the presence of anti-NT5c1A autoantibody,111 as one would expect.
Muscle Disorders
Published in Philip B. Gorelick, Fernando D. Testai, Graeme J. Hankey, Joanna M. Wardlaw, Hankey's Clinical Neurology, 2020
Kourosh Rezania, Peter Pytel, Betty Soliven
Blood tests: Serum CK level: often normal or mildly raised.21ESR: normal in 80% of cases.Antibodies to cytosolic 5’-nucleosidase 1A (anti-cN1A, aka NT5C1A antibody) is positive in about one-third of IBM patients, whereas their prevalence in dermatomyositis and polymyositis was < 5%.22, 23 Patients with SLE and Sjögren's disease may also be seropositive to NT5C1A antibody.24 Antibody to NT5C1A is a good serological biomarker for sIBM, but its specificity is not 100%, hence its presence does not obviate the need for a muscle biopsy. In an appropriate clinical setting, it is often useful to make the diagnosis of IBM.20
Clinical features and diagnostic tools in idiopathic inflammatory myopathies
Published in Critical Reviews in Clinical Laboratory Sciences, 2022
Konstantinos I. Tsamis, Constantinos Boutsoras, Evripidis Kaltsonoudis, Eleftherios Pelechas, Ilias P. Nikas, Yannis V. Simos, Paraskevi V. Voulgari, Ioannis Sarmas
CK may be normal or mildly elevated but no more than 10 times the upper limit of normal values; if it is more elevated, an alternative diagnosis should be considered. Thorough biochemical and immunological testing should be performed for two reasons, to exclude other causes of muscle weakness (electrolytes, thyroid hormones, infections, etc.) and to differentiate sIBM from other clinical conditions such as monoclonal gammopathy, Sjogren’s syndrome, systemic lupus erythematosus, sarcoidosis, human immunodeficiency virus, HTLV-1, hepatitis C, and lymphocytic leukemia, which would require investigation if present [104–108]. Recently, a new tool was added to the diagnostic armamentarium of the clinician. Although the serum autoantibody, anti-5′-nucleotidase cytosolic IA (anti-NT5C1A), is not specific for sIBM, it is present in 40–60% of sIBM cases and can support the diagnostic investigation [109–111].
Growth differentiation factor-15 as an emerging biomarker for identifying myositis
Published in Expert Review of Clinical Immunology, 2022
IBM patients are usually above the age of 50 years, and suffer from a slow progressive, asymmetrical weakness of the upper and lower limbs. The quadriceps muscle weakness leads to difficulties to rise from a chair or climb stairs, and frequent falls. Finger flexion is also typically involved. Muscle weakness may thus lead to loss of functions and an impairment in activities of daily living. An important clinical feature in many IBM patients is dysphagia, which can even be the initial presenting symptom and may be severe, resulting in aspiration. IBM’s myopathologic characteristics include invasion of non-necrotic muscle fibers by auto-aggressive cytotoxic T-cells and macrophages, with inflammation building up mostly at endomysial sites. Muscle fibers additionally develop degenerative changes, with rimmed vacuoles and inclusions containing aggregates of ectopic proteins [18]. Presence of autoantibodies direct against the cytosolic 5ʹ-nucleotidase 1A (NT5c1A) is highly specific for IBM [19]. There is no standard cure for IBM and the disorder generally does not respond to conventional immunosuppressive treatment. Many immunomodulating drugs have been tested for IBM, but so far no breakthrough has been achieved. A combination of medication and rehabilitation therapy can be beneficial for certain individuals.