Coding and coverage · ICD-10-CM

J21

J21.1 Acute bronchiolitis due to human metapneumovirus

BillableNo payment HCCChapter 10

Instructional notes

Chapter 10

Excludes2Not included here: the patient may have both; report both when both are present.
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • smoke inhalation (T59.81-)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Use additional codeAdd a second code for the full picture.
  • code, where applicable, to identify:
  • exposure to environmental tobacco smoke (Z77.22)
  • exposure to tobacco smoke in the perinatal period (P96.81)
  • history of tobacco dependence (Z87.891)
  • occupational exposure to environmental tobacco smoke (Z57.31)
  • tobacco dependence (F17.-)
  • tobacco use (Z72.0)
Notes
  • When a respiratory condition is described as occurring in more than one site and is not specifically indexed, it should be classified to the lower anatomic site (e.g. tracheobronchitis to bronchitis in J40).

Section J20-J22

Excludes2Not included here: the patient may have both; report both when both are present.
  • chronic obstructive pulmonary disease with acute lower respiratory infection (J44.0)

J21

Excludes2Not included here: the patient may have both; report both when both are present.
  • respiratory bronchiolitis interstitial lung disease (J84.115)
Includes
  • acute bronchiolitis with bronchospasm

Chapter 10: Diseases of the respiratory system · J20-J22 Other acute lower respiratory infections (J20-J22)

Source: ICD-10-CM FY 2027 code descriptions and tabular list (CMS and CDC National Center for Health Statistics), effective 2026-10-01 through 2027-09-30 · CMS ICD-10 files. HCC mapping: CMS-HCC V28, payment year 2027. As of 2026-11-04.

Coverage and payment depend on the claim details; confirm with the Medicare Administrative Contractor.