Version May 2024
| When no better explanation for the symptoms and signs exists, these classification criteria can be used. | |||
| Variable | Score points | Definition | |
| Without muscle biopsy | With muscle biopsy | ||
| Age of onset | |||
| Age of onset of first symptom assumed to be related to the disease ≥18 years and <40 years | 1.3 | 1.5 | Age ≥18 but <40 years at onset for first symptom assumed to be related to the disease. |
| Age of onset of first symptom assumed to be related to the disease ≥40 years | 2.1 | 2.2 | Age (years) at onset of first symptom assumed to be related to the disease ≥40. |
| Muscle weakness | |||
| Objective symmetric weakness, usually progressive, of the proximal upper extremities | 0.7 | 0.7 | Weakness of proximal upper extremities as defined by manual muscle testing or other objective strength testing, which is present on both sides and is usually progressive over time. |
| Objective symmetric weakness, usually progressive, of the proximal lower extremities | 0.8 | 0.5 | Weakness of proximal lower extremities as defined by manual muscle testing or other objective strength testing, which is present on both sides and is usually progressive over time. |
| Neck flexors are relatively weaker than neck extensors | 1.9 | 1.6 | Muscle grades for neck flexors are relatively lower than neck extensors as defined by manual muscle testing or other objective strength testing. |
| In the legs, proximal muscles are relatively weaker than distal muscles | 0.9 | 1.2 | Muscle grades for proximal muscles in the legs are relatively lower than distal muscles in the legs as defined by manual muscle testing or other objective strength testing. |
| Skin manifestations | |||
| Heliotrope rash | 3.1 | 3.2 | Purple, lilac-colored or erythematous patches over the eyelids or in a periorbital distribution, often associated with periorbital edema. |
| Gottron papules | 2.1 | 2.7 | Erythematous to violaceous papules over the extensor surfaces of joints, which are sometimes scaly. May occur over the finger joints, elbows, knees, malleoli, and toes. |
| Gottron sign | 3.3 | 3.7 | Erythematous to violaceous macules over the extensor surfaces of joints, which are not palpable. |
| Other clinical manifestations | |||
| Dysphagia or esophageal dysmotility | 0.7 | 0.6 | Difficulty in swallowing or objective evidence of abnormal motility of the esophagus. |
| Laboratory measurements | |||
| Anti-Jo-1 (anti-histidyl-tRNA synthetase) autoantibody present | 3.9 | 3.8 | Autoantibody testing in serum performed with standardized and validated test, showing positive result. |
| Elevated serum levels of creatine kinase (CK)* or lactate dehydrogenase (LD)* or aspartate aminotransferase (ASAT/AST/SGOT)* or alanine aminotransferase (ALAT/ALT/SGPT)* | 1.3 | 1.4 | The most abnormal test values during the disease course (highest absolute level of enzyme) above the relevant upper limit of normal. |
| Muscle biopsy features—presence of: | |||
| Endomysial infiltration of mononuclear cells surrounding, but not invading, myofibers | 1.7 | Muscle biopsy reveals endomysial mononuclear cells abutting the sarcolemma of otherwise healthy, non-necrotic muscle fibers, but there is no clear invasion of the muscle fibers. | |
| Perimysial and/or perivascular infiltration of mononuclear cells | 1.2 | Mononuclear cells are located in the perimysium and/or located around blood vessels (in either perimysial or endomysial vessels). | |
| Perifascicular atrophy | 1.9 | Muscle biopsy reveals several rows of muscle fibers, which are smaller in the perifascicular region than fibers more centrally located. | |
| Rimmed vacuoles | 3.1 | Rimmed vacuoles are bluish by H&E staining and reddish by modified Gomori trichrome stains. | |
آیا می خواهید مدیلیب را به صفحه اصلی خود اضافه کنید؟
