F84.2 vs F84.5
F84.2 and F84.5 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 F84.2
Asperger's syndrome (F84.5)
F84.2
Rett's syndrome
Billable
- Chapter 5
- Mental, Behavioral and Neurodevelopmental disorders
- Section
- F80-F89
Indexed under
- Rett's disease or syndrome
F84.5
Asperger's syndrome
Billable
- Chapter 5
- Mental, Behavioral and Neurodevelopmental disorders
- Section
- F80-F89
Use when the record says
- Asperger's disorder
- Autistic psychopathy
- Schizoid disorder of childhood
Indexed under
- Asperger's disease or syndrome
- Disorder › schizoid of childhood (of)
- Psychopathy, psychopathic › autistic
- Schizophrenia, schizophrenic › syndrome of childhood
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