DxCodebookFY2027 · Oct 1, 2026 – Sep 30, 2027

Category · FY2027

J21 Acute bronchiolitis

  • Header · not billable

J21 is not billable. The category heads 4 billable codes in FY2027: the 4 codes directly below it.

Index → code

  • Bronchiolitis (acute) (infective) (subacute) → J21.9
  • Bronchospasm (acute)withbronchiolitis, acute → J21.9
  • Virus, viralrespiratory syncytial (RSV)bronchiolitis → J21.0

Where it sits

  1. Chapter 10 Diseases of the respiratory system (J00-J99)
  2. J20-J22 Other acute lower respiratory infections (J20-J22)
  3. J21 Acute bronchiolitis
Billable codes
4
Subdivisions
4
CC / MCC codes
4 / 0
HCC V28 codes
0
New FY2027
0
Index entries
8

Codes in J21

  1. J21.0
    Acute bronchiolitis due to respiratory syncytial virus
    BillableCC
    Inclusion terms 1

    Inclusion terms

    • Acute bronchiolitis due to RSV
  2. J21.1
    Acute bronchiolitis due to human metapneumovirus
    BillableCC
  3. J21.8
    Acute bronchiolitis due to other specified organisms
    BillableCC
  4. J21.9
    Acute bronchiolitis, unspecified
    BillableCC
    Inclusion terms 1, Excludes1 1

    Inclusion terms

    • Bronchiolitis (acute)

    Excludes1

    • chronic bronchiolitis (J44.89) J44.89

CC/MCC: as a secondary diagnosis, unless the principal diagnosis is on the code’s PDX exclusion list (MS-DRG v44 Appendix C; list on the code card).

Sources of each column.

Instructions

At J21

Includes

  • acute bronchiolitis with bronchospasm

Excludes2

  • respiratory bronchiolitis interstitial lung disease (J84.115) J84.115

Notes that also apply

Block J20-J22 instructions (Excludes2 1): printed on the block page.

Chapter 10 instructions (Notes 1, Excludes2 9, Use additional code 7): printed on the chapter 10 page.

Index entries

  • Bronchiolitis (acute) (infective) (subacute) → J21.9
  • Bronchiolitis (acute) (infective) (subacute)due torespiratory syncytial virus (RSV) → J21.0
  • Virus, viralrespiratory syncytial (RSV)bronchiolitis → J21.0
  • Bronchiolitis (acute) (infective) (subacute)due tohuman metapneumovirus → J21.1
  • Bronchiolitis (acute) (infective) (subacute)due tospecified organism NEC → J21.8
  • Bronchiolitis (acute) (infective) (subacute)withbronchospasm or obstruction → J21.9
  • Bronchospasm (acute)withbronchiolitis, acute → J21.9
  • Infection, infected, infective (opportunistic)virus, viral NOSrespiratory syncytial (RSV)bronchiolitis → J21.0

NCHS Alphabetic Index. Index first, then the Tabular List.

Hierarchy