Hereditary hyperekplexia (Q101726)

Hereditary hyperekplexia is a hereditary neurological disorder characterised by excessive startle responses. Hereditary hyperekplexia manifests shortly after birth with violent jerking to noise and touch, and massive and sustained stiffening of the trunk and limbs, clenching fists, and attacks of a high-frequency trembling. Newborns are at risk for sudden infant death due to laryngospasm and cardiorespiratory failure.