Chvostek sign is described as which of the following?

Chvostek sign is described as which of the following?

• A. Twitch of the corner of the mouth on tapping CN VII at the zygoma
• B. Carpal spasm when blood pressure cuff is inflated above systolic BP
• C. Numbness around the mouth
• D. Fasciculations of the tongue

Answer: (A)

Chvostek sign reflects neuromuscular hyperexcitability from low calcium. It’s tested by tapping the facial nerve just anterior to the ear over the zygomatic arch. A positive sign is a twitch of the ipsilateral facial muscles, often at the corner of the mouth, when the nerve is stimulated. This occurs because hypocalcemia makes nerves more irritable, so a light tap triggers involuntary contraction of nearby muscles. It’s a useful clue to hypocalcemia, but not a definitive diagnosis on its own—serum calcium should be checked. This sign is distinct from Trousseau sign, which is carpal spasm produced by inflating a blood pressure cuff; numbness around the mouth can accompany hypocalcemia but is not produced by tapping, and tongue fasciculations are not characteristic of Chvostek.

Chvostek sign reflects neuromuscular hyperexcitability from low calcium. It’s tested by tapping the facial nerve just anterior to the ear over the zygomatic arch. A positive sign is a twitch of the ipsilateral facial muscles, often at the corner of the mouth, when the nerve is stimulated. This occurs because hypocalcemia makes nerves more irritable, so a light tap triggers involuntary contraction of nearby muscles. It’s a useful clue to hypocalcemia, but not a definitive diagnosis on its own—serum calcium should be checked. This sign is distinct from Trousseau sign, which is carpal spasm produced by inflating a blood pressure cuff; numbness around the mouth can accompany hypocalcemia but is not produced by tapping, and tongue fasciculations are not characteristic of Chvostek.