Dropped head syndrome as prominent clinical feature in MuSK-positive Myasthenia Gravis with thymus hyperplasia.

MuSK-positive Myasthenia Gravis is in most cases clinically characterized by a progressive course with severe oculobulbar involvement or prominent neck, shoulder and respiratory muscle weakness. It is also distinguished from other forms of myastehnia through its lack of germinal centers or lymphocytic infiltrates in the thymic tissue. We present the case of a MuSK-positive female myasthenic patient with over four years slowly progressive weakness of the neck extensor muscles in the presence of thymus hyperplasia and discuss its uncommon and markedly focal clinical and electrophysiological features, as well as the excellent course under medication with pyridostigmine and prednisone, especially after thymectomy.