A90 vs A91
A90 and A91 can never be reported together. ICD-10-CM declares them mutually exclusive with an Excludes1 note, meaning the two conditions cannot occur in the same patient — so exactly one of them is correct for any given encounter.
The official note, declared on A90
dengue hemorrhagic fever (A91)
A90
Dengue fever [classical dengue]
Billable
- Chapter 1
- Certain infectious and parasitic diseases
- Section
- A90-A99
Indexed under
- Dengue (classical) (fever)
- Fever › Aden (inanition) (of unknown origin) (persistent) (with chills) (with rigor)
- Fever › breakbone (inanition) (of unknown origin) (persistent) (with chills) (with rigor)
- Fever › dandy (inanition) (of unknown origin) (persistent) (with chills) (with rigor)
- Fever › dengue (inanition) (of unknown origin) (persistent) (with chills) (with rigor)
A91
Dengue hemorrhagic fever
Billable
- Chapter 1
- Certain infectious and parasitic diseases
- Section
- A90-A99
Indexed under
- Bangkok hemorrhagic fever
- Singapore hemorrhagic fever
- Southeast Asian hemorrhagic fever
- Thailand hemorrhagic fever
- Dengue › hemorrhagic (classical) (fever)
Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027