ICD-10-CM Code First Notes · Chapter 4 · FY 2027 E00-E89

Code First Notes in Chapter 4: Endocrine, nutritional and metabolic diseases ICD-10-CM

A Code First note means the underlying condition named in the note is sequenced before this code. In Chapter 4 (E00-E89), notes printed in the chapter name other codes 14 times, and Code First Notes anywhere in the Tabular List name the chapter’s codes 102 times, covering 64 distinct codes, categories and ranges. Switch views to read the list either way.

✓ From the official FY 2027 ICD-10-CM Tabular ListDefinitions follow the Official Guidelines, Section I.A
14
References in Its Notes
102
References to Its Codes
64
Chapter Codes Named
E00-E89
Chapter 4
Chapter 4

Code First Notes by the code that carries the note

8 of 8 shown
  • E03.2 Hypothyroidism due to medicaments and other exogenous substances
    • poisoning due to drug or toxin, if applicable (T36-T65 with fifth or sixth character 1-4)
  • E08 Diabetes mellitus due to underlying condition applies to 86 codes
    • congenital rubella (P35.0)
    • Cushing's syndrome (E24.-)
    • cystic fibrosis (E84.-)
    • malignant neoplasm (C00-C96)
    • malnutrition (E40-E46)
    • pancreatitis and other diseases of the pancreas (K85-K86.-)
  • E09 Drug or chemical induced diabetes mellitus applies to 86 codes
    • poisoning due to drug or toxin, if applicable (T36-T65 with fifth or sixth character 1-4)
  • E20.812 Autoimmune hypoparathyroidism
    • autoimmune polyglandular failure (E31.0)
    • Schmidt's syndrome (E31.0)
  • E35 Disorders of endocrine glands in diseases classified elsewhere
    • late congenital syphilis of thymus gland [Dubois disease] (A50.59)
  • E66 Overweight and obesity applies to 10 codes
    • obesity complicating pregnancy, childbirth and the puerperium, if applicable (O99.21-)
  • E88.14 HIV-associated lipodystrophy
    • any human immunodeficiency virus [HIV] disease (B20)
  • E89.1 Postprocedural hypoinsulinemia
    • , if applicable, diabetes mellitus (postpancreatectomy) (postprocedural) (E13.-)

The first view lists notes printed in this chapter (a note on a category or block applies to every code beneath it). The second lists codes of this chapter named by Code First Notes anywhere in the Tabular List, including notes in other chapters.

Questions About Code First Notes

What does a Code First note mean?

A Code First note means the underlying condition named in the note is sequenced before the code that carries the note. Under the etiology/manifestation convention, a “code first” note appears at the manifestation code and a “use additional code” note at the etiology code (Section I.A.13). The FY 2027 Tabular List has 810 of them; 600 name other codes, with 736 references to 429 distinct codes, categories and ranges.

Can a code with a Code First note be the principal diagnosis?

Not when it is a manifestation code. Codes titled “in diseases classified elsewhere” are never permitted as the first-listed or principal diagnosis; they must follow the underlying condition. The etiology and manifestation page lists them all.

Related References

ICD-10-CM Official GuidelinesICD-10-CM Code LookupICD-10-CM Codes ListCode Lists by Tag

Source: FY 2027 ICD-10-CM Tabular List (CMS and NCHS) and the ICD-10-CM Official Guidelines for Coding and Reporting FY 2027, Section I.A. ICD List is not affiliated with CMS or NCHS.