Clinical significance
Anti-striated muscle antibodies are directed against the contractile elements of striated muscle (actin, myosin, titin). They are indicated in the diagnosis of myasthenia gravis, particularly the form associated with thymoma. These antibodies can be found in other autoimmune diseases (polymyositis, rheumatoid arthritis), in transplant rejection and after a heart attack.
Clinical indications
Thymoma, myasthenia with thymoma, myasthenia.
Sample type
The patient must have a blood sample taken.
Preparation
You must fast for at least 8 hours; a small amount of water is allowed. You must have been standing or sitting upright for at least 30 minutes.
Notes
Anti-striated muscle antibodies are positive in 90% of patients with myasthenia and thymoma and in 50% of those with thymoma without myasthenia. They have been found in only 10% of cases of myasthenia without thymoma.