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ULY CLINIC

23 Septemba 2025, 12:44:14

Escherich’s sign

Escherich’s sign is a neuromuscular sign of tetany, characterized by contraction of the lips, tongue, and masseter muscles in response to percussion. It reflects increased irritability of motor nerves due to electrolyte disturbances, most commonly hypocalcemia.

Pathophysiology

Hypocalcemia lowers the threshold for depolarization of peripheral nerves.
This results in spontaneous or easily evoked action potentials, leading to muscle contractions in the face and oral region.
Escherich’s sign is similar in mechanism to Chvostek’s and Trousseau’s signs, all of which indicate neuromuscular hyperexcitability.

Examination technique

Position the patient comfortably with relaxed facial muscles.
Using a finger or reflex hammer, percuss the inner surface of the lips or the tongue.
Observe for involuntary contraction of the lips, tongue, and masseter muscles.
Note the strength and latency of the contraction.

Clinical features

Feature	Description
Motor	Contraction of lips, tongue, masseters
Onset	Immediate following percussion of lips or tongue
Associated Signs	Positive Chvostek and Trousseau signs, paresthesia, carpopedal spasm

Differential Diagnosis

Cause / Condition	Key Features	Notes
Hypocalcemia	Tetany, paresthesia, positive Chvostek/Trousseau	Most common cause of Escherich’s sign
Hypomagnesemia	May exacerbate tetany	Often coexists with hypocalcemia
Alkalosis	Can precipitate latent tetany	Check arterial blood gases
Vitamin D deficiency	Chronic hypocalcemia leading to tetany	Correct underlying deficiency

Pediatric considerations

Tetany-related signs are more prominent in neonates and infants due to immature calcium regulation.
Observe carefully to avoid excessive stimulation or distress.

Geriatric considerations

Often associated with chronic kidney disease or malnutrition, which can lead to hypocalcemia and neuromuscular excitability.

Limitations

Requires patient relaxation and proper technique; false negatives may occur in anxious or uncooperative individuals.
Should be interpreted alongside other signs of tetany.

Patient counseling

Explain that Escherich’s sign reflects nerve and muscle sensitivity due to low calcium.
Stress the importance of laboratory evaluation and correction of electrolytes.
Reassure patients that prompt treatment usually resolves the neuromuscular symptoms.

Conclusion

Escherich’s sign is a sensitive indicator of neuromuscular hyperexcitability, most commonly due to hypocalcemia. Recognition of this sign allows for early diagnosis and treatment of tetany, potentially preventing severe muscle spasms and cardiac complications.

References

Escherich T. Beobachtungen über Tetanie. Dtsch Arch Klin Med. 1883;32:177–185.
Kandel ER, Schwartz JH, Jessell TM. Principles of Neural Science. 5th ed. New York: McGraw-Hill; 2013.
Ropper AH, Samuels MA, Klein JP. Adams and Victor’s Principles of Neurology. 11th ed. New York: McGraw-Hill; 2021.
Melmed S. Hypocalcemia and Neuromuscular Manifestations. N Engl J Med. 2002;346:1310–1318.