ICD-10 E27.1
Billable / Specific HCC v28: 23 CCPrimary adrenocortical insufficiency
About ICD-10-CM E27.1
ICD-10-CM code E27.1 represents Primary adrenocortical insufficiency. This is a billable/specific code in the Endocrine, Nutritional, and Metabolic chapter (block E27). The 2026 edition of ICD-10-CM E27.1 became effective on October 1, 2025.
Coding Tips for E27.1
Specialist guidance from the PayerReady Medical Coding Team. Specificity warnings, HCC capture rules, sequencing notes.
E27.1 is a CMS-HCC v28 risk-adjustment code (category 23). To count for the patient Risk Adjustment Factor (RAF), document the diagnosis with MEAT language each calendar year: Monitored, Evaluated, Assessed, Treated. A diagnosis on the problem list alone does not satisfy CMS RADV audit standards. Include the diagnosis in the assessment with current status and current treatment plan.
E27.1 is designated CC for MS-DRG grouping. On inpatient claims, this code can shift the DRG to the with-CC variant when documented as a present-on-admission secondary diagnosis. Hospital CDI programs flag CC opportunities during chart review. Failure to capture this code may leave 30 to 80 percent of the inpatient stay revenue unrealized.
Inclusion Terms / Approximate Synonyms
Clinical terms and conditions classified under E27.1. Per CMS ICD-10-CM Tabular 2026.
- Addison's disease
- Autoimmune adrenalitis
Type 1 Excludes
Pure excludes, these codes can never be coded together with E27.1. The conditions are mutually exclusive (e.g., congenital vs acquired forms).
- Addison only phenotype adrenoleukodystrophy (E71.528)
- amyloidosis (E85.-)
- tuberculous Addison's disease (A18.7)
- Waterhouse-Friderichsen syndrome (A39.1)
Medicare Advantage HCC Impact
Capture this diagnosis annually for accurate risk adjustment. Missed HCC captures are the #1 revenue leak in Medicare Advantage risk programs.
Inpatient DRG Impact, CC
codes Primary adrenocortical insufficiency. As a Complication/Comorbidity (CC), this contributes to DRG severity adjustment when documented alongside the principal diagnosis.
Medicare LCD Coverage for E27.1
Local Coverage Determinations (LCDs) from CMS MACs that list E27.1 as a covered diagnosis.
Showing top 10 of 54 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing E27.1.
3 Medicare
CPT Codes Commonly Billed with E27.1
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
We don't have CPT pairings indexed for this specific code yet. Use the CPT search above to find common procedures, or check your payer's published medical policy for code-specific guidance.
Convert E27.1 to ICD-9-CM
Per CMS General Equivalence Mappings (GEMs), useful for legacy data review and historical claim analysis.
| ICD-10 | ICD-9 | Mapping Flags |
|---|---|---|
| E27.1 | 25541 | 10000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
Codes Adjacent To E27.1
Other codes in section E20-E35 (Disorders of other endocrine glands).
ICD-10 E27.1, Billing FAQ
Is ICD-10 code E27.1 billable? +
Yes, E27.1 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
What other names or terms map to E27.1? +
ICD-10 E27.1 includes: Addison's disease; Autoimmune adrenalitis.
What codes are Type 1 Excludes for E27.1? +
Type 1 Excludes (never code together with E27.1): Addison only phenotype adrenoleukodystrophy (E71.528); amyloidosis (E85.-); tuberculous Addison's disease (A18.7)
Does E27.1 affect Medicare Advantage HCC risk adjustment? +
Yes. E27.1 maps to CMS-HCC v28 category 23. Capture this diagnosis annually for accurate Medicare Advantage risk score.
Is E27.1 a CC or MCC for inpatient DRG? +
Yes, this code is designated as CC. Documenting as a secondary diagnosis on inpatient claims can shift the DRG to a higher-weighted category.
What ICD-9 codes does E27.1 map to? +
Per CMS GEMs, E27.1 maps to ICD-9 codes: 25541. Useful for legacy data review and historical claim analysis.
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Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on May 31, 2026.
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