E20.812

Billable

Autoimmune hypoparathyroidism

HCC Category Mapping

V24HCC 23 — Other Significant Endocrine and Metabolic Disorders

0.230

ESRDHCC 23 — Other Significant Endocrine and Metabolic Disorders

0.000

RxHCCHCC 43 — Other Significant Endocrine and Metabolic Disorders

0.000

What This Code Means

A condition where the immune system attacks and damages the parathyroid glands, preventing them from producing adequate parathyroid hormone.

Coding Tips

•Document evidence of autoimmune involvement such as antibodies or associated autoimmune conditions
•This code indicates an immune-mediated mechanism, distinguishing it from idiopathic hypoparathyroidism

Clinical Significance

E20.812 identifies autoimmune hypoparathyroidism, where the immune system attacks and destroys the parathyroid glands. This condition may occur in isolation or as part of autoimmune polyendocrine syndrome type 1 (APS-1/APECED syndrome), which also includes chronic mucocutaneous candidiasis and adrenal insufficiency. Early recognition is important for screening for associated autoimmune conditions.

Documentation Requirements

✓Documentation must include the diagnosis of autoimmune hypoparathyroidism with supporting evidence such as anti-parathyroid antibodies, low parathyroid hormone levels, hypocalcemia, and clinical context suggesting autoimmune etiology.
✓Evaluation for associated autoimmune conditions and any component of autoimmune polyendocrine syndrome should be documented.

Code First

, if applicable, underlying condition such as:
autoimmune polyglandular failure (E31.0)
Schmidt's syndrome (E31.0)

Commonly Confused Codes

E20.0 (idiopathic hypoparathyroidism) when autoimmune testing has not been performed E20.810 (autosomal dominant hypocalcemia) for genetic rather than autoimmune etiology E31.0 (autoimmune polyglandular failure) when multiple endocrine glands are affected.

Code Hierarchy

└E20Hypoparathyroidism └E20.8Other hypoparathyroidism └E20.81Hypoparathyroidism due to impaired parathyroid hormone secretion └E20.812Autoimmune hypoparathyroidism

└E20.812Autoimmune hypoparathyroidism