ICD-10-CM 2027
ICD-10 code for Nelson's syndrome
From the official ICD-10-CM alphabetic index entry “Nelson's syndrome”. Page updated September 29, 2026.
About coding Nelson's syndrome
The ICD-10-CM code for Nelson's syndrome is E24.1 (Nelson's syndrome).
Within E24 (Cushing's syndrome), E24.1 is specifically for Nelson's syndrome. Related codes cover Pituitary-dependent Cushing's disease (E24.0), drug-induced Cushing's syndrome (E24.2), ectopic ACTH syndrome (E24.3), alcohol-induced pseudo-Cushing's syndrome (E24.4), other Cushing's syndrome (E24.8) and unspecified (E24.9).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 643 (Endocrine Disorders with MCC, relative weight 1.6139), DRG 644 (Endocrine Disorders with CC, relative weight 1.0044) and DRG 645 (Endocrine Disorders without CC/MCC, relative weight 0.7459), in MDC 10 (Endocrine, Nutritional and Metabolic Diseases and Disorders), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
Common questions about Nelson's syndrome ICD-10 codes
What is the ICD-10 code for Nelson's syndrome?
- E24.1 — Nelson's syndrome.
Is E24.1 billable?
- Yes. E24.1 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can E24.1 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict E24.1 as a principal diagnosis.
Is E24.1 a CC or MCC?
- No. E24.1 is neither a CC nor an MCC under MS-DRG v44.0.