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Musk-antibody positive myasthenia gravis presenting with isolated neck extensor weakness
C Casasnovas1, M Povedano, S Jaumà
1Neuromuscular Unit, Department of Neurology, Hospital Universitari de Bellvitge-IDIBELL, Feixa Llarga S/N 08907, L'Hospitalet de Llobregat, Barcelona, Spain. carloscasasnovas@csub.scs.es
Abstract:
Dropped head sign is characterized by the gradual forward sagging of the head due to weakness of neck extensor muscles. This may be a prominent sign of several neuromuscular disorders and may be an isolated feature of myasthenia gravis (MG). We describe a patient with isolated neck extensor weakness, eletrophysiological findings suggesting myasthenia gravis and positive MuSK antibodies. This case supports that finding anti-MuSK antibodies may be extremely helpful in dropped head patients and negative acetylcholine receptor antibodies especially if needle EMG does not reveal myopathic or neurogenic patterns.
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