E20.810

HCC Category Mapping

What This Code Means

A rare inherited condition where low calcium levels in the blood are caused by an autosomal dominant genetic mutation affecting calcium regulation.

Coding Tips

• •This is a specific genetic subtype; ensure genetic testing or family history documentation supports this diagnosis
• •Code separately from other forms of hypoparathyroidism as this represents a distinct genetic etiology

Clinical Significance

E20.810 identifies autosomal dominant hypocalcemia, a genetic disorder caused by activating mutations in the calcium-sensing receptor gene, leading to inappropriate suppression of parathyroid hormone secretion. Patients present with chronic hypocalcemia and relative hypercalciuria, distinguishing this condition from other forms of hypoparathyroidism and requiring specialized management to avoid nephrocalcinosis.

Documentation Requirements

• ✓Documentation must include the genetic diagnosis or strong clinical suspicion of autosomal dominant hypocalcemia with confirmatory genetic testing.
• ✓Laboratory findings including low parathyroid hormone, hypocalcemia, and inappropriately normal or elevated urinary calcium excretion should be documented.
• ✓Family history is important.

Commonly Confused Codes