18 Case 1

A 20-year-old male had full manifestation of Coffin-Lowry syndrome and 6 year history of progressively severe drop episodes. His drop episodes were precipitated by unexpected sudden auditory stimuli, and were not associated with electroencephalographical changes. The positron emission tomography disclosed metabolic reduction over bilateral temporal-parietal cortex which could contribute to his exaggerated startle reaction .His drop attack was abolished by clonazepam suggesting that GABAnergic pathway might participate in the neuronal circuit of startle reaction. Thus, we suggest that cortical hypometabolism and GABAergic system play a critical role in the pathophysiology of drop episode of Coffin-Lowry syndrome and that early introduction of clonazepam may prevent further injury and restore his ambulatory capacity. Retrospectively, early signs of Coffin-Lowry syndrome could be a premature loss of primary teeth and myopia. His premature loss of exfoliative tooth occurred at 7 years of age but was misdiagnosed. Besides, myopia could be another early sign of Coffin-Lowry syndrome which be developed at 10 years of age. Both myopia-associated staphyloma and reduced teeth number could be identified in the cerebral magnetic resonance imaging (MRI) and the plain skull film. Suggesting the important role of cerebral imaging study in the diagnosis of Coffin-Lowry syndrome.