Test Code (รหัสการทดสอบ):
090-70-8601
Order Name (ชื่อการทดสอบ):
Myositis Profile, Immunoblot
Clinical Information (ข้อมูลทางคลินิก):
Myositis is an inflammatory disease of skeletal muscles, which can be either hereditary or triggered by infections, toxins or immune system disorders. The autoimmunogenic myositides (idiopathic inflammatory myopathies) are systemic autoimmune diseases with inflammation of the skeletal musculature, symmetric and proximal accentuated pain and muscle weakness. They occur with an incidence of 0.1 to 1 per 100,000 per year, a prevalence of 1 to 6 per 100,000 and ratio of men to women of 1 to 2. They can be divided into polymyositis in adults (around 30%), dermatomyositis in adults (around 30%), paraneoplastic polymyositis of the lungs, ovaries, mammary glands, gastrointestinal tract and in myeloproliferative diseases (around 8%), infantile myositis/dermatomyositis with accompanying vasculitis (around 7%), as well as myositides in association with autoimmune diseases such as rheumatoid arthritis, lupus erythematosus, mixed connective tissue disease (MCTD) and rare forms such as granulomatosis, eosinophile, focal and inclusion body myositis (around 20%). It should be noted that dermato-/polymyositis is often of paraneoplastic origin, particularly in elderly patients. Dermatomyositis symptoms can occur before the tumour is even diagnostically detectable
Reference Value (ค่าอ้างอิง):
| Anti Mi-2α |
Negative |
| Anti Mi-2β |
Negative |
| Anti TIF1γ |
Negative |
| Anti MDA5 |
Negative |
| Anti NXP2 |
Negative |
| Anti SAE1 |
Negative |
| Anti Ku |
Negative |
| Anti PM-Scl100 |
Negative |
| Anti PM-Scl75 |
Negative |
| Anti Jo-1 |
Negative |
| Anti SRP |
Negative |
| Anti PL-7 |
Negative |
| Anti PL-12 |
Negative |
| Anti EJ |
Negative |
| Anti OJ |
Negative |
| Anti Ro-52 |
Negative |
| Anti cN-1A |
Negative |
| Anti HMGCR |
Negative |
Interpretation (การแปลผล):
Findings in laboratory diagnostics include increased muscle enzyme values and unspecific signs of inflammation, such as increased CRP titer, fever, and acceleration of ESR. The detection of myositisassociated autoantibodies is of decisive importance for the diagnosis of dermatomyositis, as well as for assessment of the disease and treatment course. Although the mortality rate is increased by a factor of four (most frequent causes of death are heart and lung diseases), half of patients recover fully, although a slight weakness of the muscles may remain. In 30% of cases the disease can be stopped. 20% of patients experience deterioration despite therapeutic measures. Autoantibodies of immunoglobulin class IgG against the 18 most important and most relevant of the currently known myositis-specific and myositis-associated DM/PM and overlap antigens can be detected in serum or plasma. These comprise Mi-2 (isoforms Mi-2α and Mi-2β), TIF1g, MDA5, NXP2, SAE1, Ku, proteins of the nucleolar PM-Scl macromolecular complex (PM-Scl100 and PM-Scl75), Jo-1, SRP, PL-7, PL-12, EJ, OJ, Ro-52, cN-1A and HMGCR.
Clinical Reference (เอกสารอ้างอิง):
Manufacturer’s reagent package insert, EUROLINE Autoimmune Inflammatory Myopathies 16 Ag et cN-1A et HMGCR (IgG), March 2023, EUROIMMUN, Lübeck, D-23560 Germany.