Inclusion body myositis
Introduction
Introduction to inclusion body myositis Inclusion body myositis is a special type of idiopathic inflammatory myopathy. Adams et al. (1965) first reported the pathological features of intracytoplasmic and intranuclear inclusions in this disease, and noted many of the characteristic clinical manifestations of the disease. Some authors estimate that IBM accounts for about one-third of patients with inflammatory myopathy, especially male patients. basic knowledge The proportion of illness: 0.003% Susceptible people: no specific people Mode of infection: non-infectious Complications: Acne
Cause
Inclusion body myositis
The etiology of this disease is unclear, and there is evidence that T cell-mediated myocyte toxicity and multi-factor genetic susceptibility are involved in the pathogenesis. The disease can be autosomal dominant and recessive, most of which are sporadic cases. Many autosomal recessive familial inclusion body myopathy is due to the staining of 9p1-q1, but not all patients.
Prevention
Inclusion body myositis prevention
There is no effective prevention method, symptomatic treatment, and strengthening clinical medical care, which is an important part of improving the quality of life of patients. It has been reported that the disease can be satisfied with a longer period of relief, especially in children. Adult patients can die from severe progressive muscle weakness, difficulty swallowing, malnutrition, and respiratory failure due to aspiration pneumonia or repeated intrapulmonary infections. Polymyositis with heart, lung lesions, the condition is often serious, and the treatment is not good. Children usually die of vasculitis in the intestines. The prognosis of patients with myositis complicated with malignant tumors generally depends on the prognosis of malignant tumors.
Complication
Inclusion body myositis complications Complications
No special records, limb weakness, long-term bed rest and difficulty swallowing, can lead to hemorrhoids and lung infections. Compared with the incidence of visceral lesions in other connective tissue diseases (such as systemic lupus erythematosus, progressive systemic sclerosis), visceral complications of polymyositis (except pharyngeal and esophageal) are rare, but occasionally visceral involvement The performance appeared before the muscles were weak. Interstitial pneumonia (expressed as dyspnea and cough) can occur and can be a major clinical manifestation. According to reports, the incidence of cardiac involvement is gradually increasing, mainly due to abnormal ECG, such as arrhythmia, conduction disorder, and abnormal intersystolic phase. In some cases, acute renal failure occurs due to severe rhabdomyolysis, accompanied by myosinuria (squeezing syndrome). Some patients have Sjogren syndrome. Abdominal symptoms are more common in children, may have hematemesis or melena, caused by gastrointestinal ulcers, can develop into perforations, and therefore require surgical treatment.
Symptom
Inclusion body myotitis symptoms Common symptoms Shoulder muscles, upper limbs and... Shoulder joint mobility restricted dysphagia
1. The disease is more common in men, with a male to female ratio of about 3:1. Usually after the age of 50, insidious onset, progressive lower limb painless muscle weakness and muscle atrophy, and then upper limbs also appear, distal muscle weakness is often not as severe as the proximal end, usually bilateral asymmetry, but also selectively involved Muscles, which develop to other muscle groups after months or years, are characteristic changes in the extensor hallucis longus. The disease is progressive, with early knee reflexes reduced. Dysphagia is more common, and a few types of cardiovascular abnormalities can be seen in a few cases.
2, familial IBM muscle weakness begins in early childhood, usually does not involve the quadriceps muscle, unlike sporadic cases, familial cases of muscle lack of inflammatory changes, so called familial inclusion body myopathy is more accurate.
Examine
Examination of inclusion body myositis
EMG:
Electromyography is a means of assisting the examination of diseases through myoelectricity. The use of electronic instruments to record the electrical activity of muscles at rest or contraction, and the application of electrical stimulation to examine nerve and muscle excitation and conduction functions. English referred to as EMG. Through this examination, the functional status of peripheral nerves, neurons, neuromuscular junctions, and muscles themselves can be determined.
Muscle biopsy:
In order to diagnose or differentially diagnose neuromuscular diseases, doctors take out muscles (soy size) from certain parts of the body for microscopic or electron microscopic examination. The location of the muscle removed is determined by the nature of the myopathy (distal or proximal involvement?) and the extent of the disease progression. Muscle biopsy is a traumatic examination, but it cannot be replaced by other examinations at present, and all auxiliary examinations, including genetic testing, cannot replace muscle biopsy.
Serum muscle enzyme test s-IBM serum CK levels can be normal or slightly increased, generally not more than 10 to 12 times the normal value.
EMG examination s-IBM's EMG characteristics are similar to those of PM-DM, showing an increase in abnormal spontaneous activity, increased short-term exercise unit potential and multiphase waves. The difference is that s-IBM long-term and short-duration motion units can occur simultaneously in the same muscle, the latter being called mixed electric potentials.
Diagnosis
Diagnosis and differentiation of inclusion body myositis
1. Serum CK levels are normally mildly elevated.
2, the EMG abnormality of this disease is similar to PM, a small number of patients show neurogenic changes such as muscle fibrillation potential, especially the distal muscle of the limb.
3, muscle histological examination showed abnormal inflammatory changes in muscle fiber structure, CD8 T cell infiltration. The diagnosis requires the use of immunohistochemical techniques to detect the formation of vesicles and nucleus vacuoles of degenerative muscle fibers, and the -amyloid protein is positively stained (ephemeral inclusions). Unlike the vacuoles seen in some PM cases, there are basophilic particulate matter in or around the vacuole.
