Hyperekplexia is a rare, nonepileptic, genetic, or sporadic neurologic disorder characterized by startle responses to acoustic, optic, or tactile stimuli. Genetic defects in glycine receptors as well as encephalitis, tumors, inflammation, and disgenesis are among the etiologic causes of the disease. The main problem in hyperekplexia is the incomplete development of inhibitory mechanisms or exaggerated stimulation of excitatory mediators. Hyperekplexia is often confused with epileptic seizures. Here we present a case with hypoglycemic convulsions coexisting with hyperekplexia, causing diagnostic difficulty. 1. Introduction Hyperekplexia (HE), first described by Kirstein and Silfverskiold in 1958, is a rare and nonepileptic clinical entity characterized by exaggerated and generalized startle responses to acoustic, optic, or tactile stimuli [1]. Minimal stimuli can cause severe jerk-like movements in all the limbs. The symptoms of the disease can lead to unavoidable falls with no loss of consciousness that often diminish with age or continue until adulthood. Glycine is one of the major inhibitory neurotransmitters in the central nervous system. The glycine receptors cause postsynaptic hyperpolarization and synaptic inhibition through chlorine channels in brain and brain stem. The main pathologic impairment is the inability of glycine, which is one of the major inhibitory neurotransmitters in the central nervous system, to display its inhibitory effects, particularly in the brain stem [2]. Hyperekplexia is known to be genetic or sporadic with the genetic form being more frequent. Genetic studies have shown that most of the genetic cases are autosomal dominant and that the responsible gene is found in the alpha-1 and beta subunits and glycine-carrying parts of glycine receptors as well as in the proteins of gephyrin and collybistin that both have glycine-like effects [3]. The sporadic cases of HE are rare and are either idiopathic or due to factors such as encephalitis, tumors, inflammation, and disgenesis [4]. Hypoglycemia is a frequent problem in the newborn. Serious hypoglycemia can lead to optic and mental disorders, epilepsy, and brain damage. Hypoglycemia causes convulsions by increasing glutamate, the main excitatory neurotransmitter of the brain [5]. 2. Case The baby boy was born full-term by spontaneous vaginal delivery to a 28-year-old healthy female mother as a fifth pregnancy. Immediately after birth, the infant cried but displayed no change in skin color, and his Apgar scores were 7 and 9 at one and 5 minutes, respectively. There was no history
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