Early onset myasthenia gravis with atypical features.

A 14 year old boy with atypical myasthenia gravis is reported. The interesting features of the case were the onset in first decade with progressive weakness of limb muscles simulating limb girdle myopathy, presence of bilateral symmetrical non fluctuating external ophthalmoplegia with ptosis and the absence of diplopia. Differential response to choline esterase inhibitors was clinically apparent. In contrast to excellent improvement in limb weakness with choline esterase inhibitors, there was no improvement in external ophthalmoplegia or ptosis. The possibilities are discussed and literature is reviewed.