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A91

A91Dengue hemorrhagic fever

Billable / specific codeICD-10-CM

A91 is a billable, specific ICD-10-CM code for dengue hemorrhagic fever. It is valid for submission on a claim.

Other codes that can never be billed with A91

These codes carry an Excludes1 note pointing at A91. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading A91 alone.

  • A90Dengue fever [classical dengue]
  • A98Other viral hemorrhagic fevers, not elsewhere classified

Risk adjustment

A91 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

How A91 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to A91.

  • Bangkok hemorrhagic fever
  • Singapore hemorrhagic fever
  • Southeast Asian hemorrhagic fever
  • Thailand hemorrhagic fever
  • Denguehemorrhagic
  • FeverBangkok hemorrhagic
  • FeverPhilippine hemorrhagic
  • FeverSingapore hemorrhagic
  • FeverSoutheast Asia hemorrhagic
  • FeverThailand hemorrhagic
  • Feverdenguehemorrhagic
  • Feverhemorrhagic NOSBangkok

Questions about A91

Is A91 a billable ICD-10-CM code?
Yes. A91 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does A91 sit in the tabular list?
Certain infectious and parasitic diseases (A00-B99), in the block Arthropod-borne viral fevers and viral hemorrhagic fevers (A90-A99).
ICD-10-CMFY2026-Apr· effective April 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release — see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.