E20.818

HCC Category Mapping

What This Code Means

This condition occurs when the parathyroid glands fail to produce adequate parathyroid hormone, leading to low calcium levels in the blood. It is a rare form of hypoparathyroidism caused by impaired hormone secretion rather than other causes.

Coding Tips

• •Verify the documentation specifies that the hypoparathyroidism is due to impaired parathyroid hormone secretion, as this distinguishes it from other hypoparathyroidism subtypes (such as surgical removal or genetic forms)
• •Ensure the physician has documented this as 'other specified' rather than unspecified, as E20.9 would be used if the specific type cannot be determined

Clinical Significance

E20.818 captures other specified hypoparathyroidism due to impaired parathyroid hormone secretion not classified as idiopathic, autosomal dominant, secondary, or autoimmune. This may include hypoparathyroidism due to infiltrative processes directly affecting the parathyroid glands, mitochondrial disorders, or other rare genetic conditions affecting parathyroid hormone synthesis or secretion.

Documentation Requirements

• ✓Documentation must confirm hypoparathyroidism with impaired secretion, identify the specific cause, and exclude the more common etiologies that have their own codes.
• ✓Laboratory evidence of low parathyroid hormone, hypocalcemia, and the underlying pathology should be documented.

Commonly Confused Codes