A Neonate with Exaggerated Startle and Tonic Spasms

Abstract

Hyperekplexia is a rare, potentially treatable inherited disorder of glycinergic neurotransmission, which is characterized by neonatal onset exaggerated startle response to somatosensory, auditory stimuli, and episodic tonic spasm. Prolonged tonic spasms can be life-threatening and associated with apnea and bradycardia. Awareness about this condition avoids misdiagnosis such as tonic seizures and epilepsy. We describe a term newborn with episodic tonic stiffness mistaken for seizures. Classical exaggerated startle reaction, positive head retraction response to glabellar tap, and characteristic video electroencephalogram confirmed the diagnosis.

Keywords

neonate - spasm - seizures - startle - glabellar tap

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