Phenotypes associated with the disease Inclusion body myositis (ORPHA:611, an Orphanet rare-disease identifier):
- Autoimmunity (HP:0002960, a Human Phenotype Ontology term): The occurrence of an immune reaction against the organism's own cells or tissues. Evidence: TAS. Frequency: Very frequent (HP:0040281, a Human Phenotype Ontology term). (ORPHA:611)
- Ragged-red muscle fibers (HP:0003200, a Human Phenotype Ontology term): An abnormal appearance of muscle fibers observed on muscle biopsy. Ragged red fibers can be visualized with Gomori trichrome staining as irregular and intensely red subsarcolemmal zones, whereas the normal myofibrils are green. The margins of affect fibers appear red and ragged. The ragged-red is due to the accumulation of abnormal mitochondria below the plasma membrane of the muscle fiber, leading to the appearance of a red rim and speckled sarcoplasm. Evidence: TAS. Frequency: Very frequent (HP:0040281, a Human Phenotype Ontology term). (ORPHA:611)
- Skeletal muscle atrophy (HP:0003202, a Human Phenotype Ontology term): The presence of skeletal muscular atrophy (which is also known as amyotrophy). Evidence: TAS. Frequency: Very frequent (HP:0040281, a Human Phenotype Ontology term). (ORPHA:611)
- Elevated circulating creatine kinase activity (HP:0003236, a Human Phenotype Ontology term): The activity of creatine kinase in the blood circulation is above the upper limit of normal. Evidence: TAS. Frequency: Very frequent (HP:0040281, a Human Phenotype Ontology term). (ORPHA:611)
- EMG abnormality (HP:0003457, a Human Phenotype Ontology term): Abnormal results of investigations using electromyography (EMG). Evidence: TAS. Frequency: Very frequent (HP:0040281, a Human Phenotype Ontology term). (ORPHA:611)
- Proximal muscle weakness (HP:0003701, a Human Phenotype Ontology term): A lack of strength of the proximal muscles. Evidence: TAS. Frequency: Very frequent (HP:0040281, a Human Phenotype Ontology term). (ORPHA:611)
- Quadriceps muscle weakness (HP:0003731, a Human Phenotype Ontology term): Weakness of the quadriceps muscle (that is, of the muscle fasciculus of quadriceps femoris). Evidence: TAS. Frequency: Very frequent (HP:0040281, a Human Phenotype Ontology term). (ORPHA:611)
- Rimmed vacuoles (HP:0003805, a Human Phenotype Ontology term): Presence of abnormal vacuoles (membrane-bound organelles) in the sarcolemma. On histological staining with hematoxylin and eosin, rimmed vacuoles are popcorn-like clear vacuoles with a densely blue rim. The vacuoles are often associated with cytoplasmic and occasionally intranuclear eosinophilic inclusions. Evidence: TAS. Frequency: Very frequent (HP:0040281, a Human Phenotype Ontology term). (ORPHA:611)
- Abnormal muscle fiber morphology (HP:0004303, a Human Phenotype Ontology term): Any abnormality of the skeletal muscle cell. Muscle fibers are subdivided into two types. Type I fibers are fatigue-resistant and rich in oxidative enzymes (they stain light with the myosin ATPase reaction), and type II fibers are fast-contracting, fatigue-prone, and rich in glycolytic enzymes (these fibers stain darkly). Normal muscle tissue has a random distribution of type I and type II fibers. Evidence: TAS. Frequency: Very frequent (HP:0040281, a Human Phenotype Ontology term). (ORPHA:611)
- Inflammatory myopathy (HP:0009071, a Human Phenotype Ontology term): Chronic muscle inflammation accompanied by muscle weakness. Evidence: TAS. Frequency: Very frequent (HP:0040281, a Human Phenotype Ontology term). (ORPHA:611)
- Diminished deep tendon reflex (HP:0001315, a Human Phenotype Ontology term): A reduction (hyporeflexia) or complete absence (areflexia) of the involuntary muscle contraction normally elicited by a reflex stimulus, such as tapping a deep tendon. Evidence: TAS. Frequency: Frequent (HP:0040282, a Human Phenotype Ontology term). (ORPHA:611)
- Feeding difficulties in infancy (HP:0008872, a Human Phenotype Ontology term): Impaired feeding performance of an infant as manifested by difficulties such as weak and ineffective sucking, brief bursts of sucking, and falling asleep during sucking. There may be difficulties with chewing or maintaining attention. Evidence: TAS. Frequency: Frequent (HP:0040282, a Human Phenotype Ontology term). (ORPHA:611)
- Anti-cytosolic-5-nucleotidase-1A antibody positivity (HP:0034153, a Human Phenotype Ontology term): The presence of autoantibodies (immunoglobulins) in the blood circulation that react against cytosolic-5-nucleotidase-1A (cN1A). Evidence: TAS. Frequency: Frequent (HP:0040282, a Human Phenotype Ontology term). (ORPHA:611)
- Myalgia (HP:0003326, a Human Phenotype Ontology term): Pain in muscle. Evidence: TAS. Frequency: Occasional (HP:0040283, a Human Phenotype Ontology term). (ORPHA:611)