Abstract

Lid twitch sign also called as Cogan sign is characteristic of Myasthenia Gravis. It is elicited by asking the patient to look down for 10- 15 seconds and then to look straight during which there is a twitch in the upper eye lid. The exact pathophysiology is unclear. However the twitch is proposed to be secondary to initial fatigability followed by recovery of levator muscle. Here we present a child with drooping of eye lids and ophthalmoplegia with Cogan lid twitch sign mimicking myasthenia gravis. But child had associated walking difficulty which prompted us to evaluate for Miller fisher variant of Gullain Barre syndrome. She was noted positive for anti GQ1 antibody. Post treatment with systemic steroids child showed improvement .We conclude that it’s important to understand that Cogan’s lid twitch sign is not pathognomonic for Myasthenia gravis and can be seen conditions like Miller fisher variant.