ICD-10-CM Code First Notes · Chapter 22 · FY 2027 U00-U49

Code First Notes in Chapter 22: Codes for Special Purposes ICD-10-CM

A Code First note means the underlying condition named in the note is sequenced before this code. In Chapter 22 (U00-U49), notes printed in the chapter name other codes 6 times, and Code First Notes anywhere in the Tabular List name the chapter’s codes 3 times, covering 1 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
6
References in Its Notes
3
References to Its Codes
1
Chapter Codes Named
U00-U49
Chapter 22
Chapter 22

Code First Notes by the code that carries the note

1 of 1 shown
  • U09.9 Post COVID-19 condition, unspecified
    • chronic respiratory failure (J96.1-)
    • loss of smell (R43.8)
    • loss of taste (R43.8)
    • multisystem inflammatory syndrome (M35.81)
    • pulmonary embolism (I26.-)
    • pulmonary fibrosis (J84.10)

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

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.