ICD-10-CM 2027
ICD-10 code for adenoid infection
From the official ICD-10-CM alphabetic index entry “Infection, infected, infective (opportunistic) › adenoid (and tonsil)”. Page updated September 29, 2026.
About coding adenoid infection
The ICD-10-CM code for adenoid infection is J03.90 (Acute tonsillitis, unspecified). The official index lists 1 more specific code, so check the documentation for details such as type, cause, site or severity before settling on J03.90.
Within J03.9, choose J03.90 (tonsillitis, unspecified) only when documentation doesn't support a more specific option: recurrent tonsillitis, unspecified (J03.91).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 011 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy with MCC, relative weight 5.6154), DRG 012 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy with CC, relative weight 4.381), DRG 013 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy without CC/MCC, relative weight 2.7307), DRG 152 (Otitis Media and URI with MCC, relative weight 1.1151) and DRG 153 (Otitis Media and URI without MCC, relative weight 0.7421), in Pre-MDC and MDC 03 (Diseases and Disorders of the Ear, Nose, Mouth and Throat), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific adenoid infection codes (official index)
- chronic J35.02 — Chronic adenoiditis
Common questions about adenoid infection ICD-10 codes
What is the ICD-10 code for adenoid infection?
- J03.90 — Acute tonsillitis, unspecified. More specific codes apply when the documentation supports them: J35.02.
What is the ICD-10 code for chronic adenoid infection?
- J35.02 — Chronic adenoiditis.
Is J03.90 billable?
- Yes. J03.90 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can J03.90 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict J03.90 as a principal diagnosis.
Is J03.90 a CC or MCC?
- No. J03.90 is neither a CC nor an MCC under MS-DRG v44.0.