The Chvostek sign (/ˈkvɒstɪk/) is a clinical sign of existing nerve hyperexcitability (tetany) seen in hypocalcemia.It refers to an abnormal reaction to the stimulation of the facial nerve. When the facial nerve is tapped in front of tragus the facial muscles on the same side of the face will contract momentarily (typically a twitch of the nose or lips) because of hypocalcemia (i.e. from hypoparathyroidism, pseudohypoparathyroidism, hypovitaminosis D) with resultant hyperexcitability of nerves. Though classically described in hypocalcemia, this sign may also be encountered in respiratory alkalosis, such as that seen in hyperventilation, which causes decreased serum Ca2+ with a normal calcium level due to a shift of Ca2+ from the blood to albumin which has become more negative in the alkalotic state. #Chvostek #Signs #Hypocalcemia #PhysicalExam #Video #Clinical #endocrinology
