Specific autoantibodies (AChR, MuSK, Lrp4) should not be required as a profile when myasthenia gravis is suspected, but the initial test is represented only by anti-AchR antibodies. The determination of anti-Musk antibodies should be reserved for anti-AChR negative patients, while that of anti-Lrp4 antibodies should be limited to anti-AChR and anti-MuSK negative patients.
Since the three autoantibodies are mutually exclusive, it is not useful to simultaneously request the determination of all three antibodies, because about 80% of patients with myasthenia have only anti-AChR, 16% only anti-MuSK and the remaining 4% only anti-Lrp4 antibodies.
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2. Evoli A (2017) Myasthenia gravis: new developments in research and treatment. Curr Opin Neurol 30:464-470
3. Gilhus NE (2016) Myasthenia gravis. N Engl J Med 375:2570-2581
4. Zisimopoulou P, Evangelakou P, Tzartos J, Lazaridis K, Zouvelou V, Mantegazza R et al (2014) A comprehensive analysis of the epidemiology and clinical characteristics of anti-LRP4 in myasthenia gravis. J Autoimmun 52:139-145
Attention. Please note that these items are provided only for information and are not intended as a substitute for consultation with a clinician. Patients with any specific questions about the items on this list or their individual situation should consult their clinician.