B37 vs N77.1
B37 and N77.1 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 N77.1
candidal vulvovaginitis (B37.3-)
B37
Candidiasis
Not billable
- Chapter 1
- Certain infectious and parasitic diseases
- Section
- B35-B49
Use when the record says
- candidosis
- moniliasis
N77.1
Vaginitis, vulvitis and vulvovaginitis in diseases classified elsewhere
Billable
- Chapter 14
- Diseases of the genitourinary system
- Section
- N70-N77
Indexed under
- Vaginitis › in › pinworm infection (acute) (circumscribed) (diffuse) (emphysematous) (nonvenereal) (ulcerative)
These two codes sit in different chapters of the Tabular List, which is usually the clearest signal that they describe different underlying processes rather than different degrees of the same one.
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