Measurement of acetylcholine receptor antibodies is used to diagnose severe myasthenia (Myasthenia Gravis) and to monitor the patient's response to immunosuppressive therapy.
Acetylcholine (ACh) and catecholamines (epinephrine or adrenaline and norepinephrine or noradrenaline) are the major neurotransmitters of the autonomic nervous system. During normal contraction of the muscles, acetylcholine is released from the terminal end of the nerve into the neuromuscular junction. Acetylcholine then binds to its receptor (AChR) on the plasma membrane of the muscle cells, thereby opening the sodium channels. This allows sodium ions to enter the cell and depolarize it. This initiates a potential for action that runs along the entire muscle fiber, resulting in muscle contraction.
Severe myasthenia (Myasthenia Gravis) is an autoimmune disease that affects neuromuscular transmission. In this disease, antibodies interfere with the binding of acetylcholine to its receptor sites on the muscle cell membrane, thereby preventing muscle contraction. These antibodies are found in more than 85% of patients with severe myasthenia.
False-positive results may occur in patients with amyotrophic lateral sclerosis (ALS). Immunosuppressive drugs may decrease the titer of acetylcholine receptor antibodies.
See also: Muscle-Specific Kinase (MuSK) Antibodies, LRP4 Antibodies
Important Note
Laboratory test results are the most important parameter for the diagnosis and monitoring of all pathological conditions. 70%-80% of diagnostic decisions are based on laboratory tests. The correct interpretation of laboratory results allows a doctor to distinguish "healthy" from "diseased".
Laboratory test results should not be interpreted from the numerical result of a single analysis. Test results should be interpreted in relation to each individual case and family history, clinical findings, and the results of other laboratory tests and information. Your personal physician should explain the importance of your test results.
At Diagnostiki Athinon we answer any questions you may have about the test you perform in our laboratory and we contact your doctor to get the best possible medical care.