E24.1

Billable

Nelson's syndrome

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 that develops after surgical removal of a pituitary tumor, characterized by high ACTH and cortisol levels due to remaining pituitary tissue.

Coding Tips

•This code is specific to post-surgical pituitary tumor removal; document the history of pituitary surgery
•Often associated with a history of Cushing's disease that was surgically treated

Clinical Significance

Nelson syndrome is a rare but serious complication that develops after bilateral adrenalectomy for Cushing disease, where the pre-existing pituitary corticotroph adenoma grows aggressively due to loss of cortisol negative feedback. It manifests with skin hyperpigmentation, elevated adrenocorticotropic hormone, and potentially invasive pituitary tumor behavior.

Documentation Requirements

✓Document the history of bilateral adrenalectomy for Cushing disease, current adrenocorticotropic hormone levels, pituitary MRI showing tumor growth, skin hyperpigmentation, visual field assessment, and current management (radiation therapy, repeat surgery, medical therapy).

Commonly Confused Codes

E24.0 (pituitary-dependent Cushing disease, the precursor condition), E24.8 (other Cushing syndrome), D35.2 (benign neoplasm of pituitary gland which should be coded separately if the adenoma is present).

Code Hierarchy

└E24Cushing's syndrome └E24.1Nelson's syndrome

└E24.1Nelson's syndrome