ICDcodes.org
FY2027

F84.0 vs F84.3

F84.0 and F84.3 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 F84.3
Autistic disorder (F84.0)
F84.0

Autistic disorder

Billable
Chapter 5
Mental, Behavioral and Neurodevelopmental disorders
Section
F80-F89
Use when the record says
  • Autism spectrum disorder
  • Infantile autism
  • Infantile psychosis
  • Kanner's syndrome
Indexed under
  • Autism, autistic (childhood) (infantile)
  • Autism, autistic › spectrum disorder (childhood) (infantile)
  • Disorder › autistic (of)
  • Disorder › autism spectrum (of)
  • Psychosis, psychotic › childhood
F84.3

Other childhood disintegrative disorder

Billable
Chapter 5
Mental, Behavioral and Neurodevelopmental disorders
Section
F80-F89
Use when the record says
  • Dementia infantilis
  • Disintegrative psychosis
  • Heller's syndrome
  • Symbiotic psychosis
Indexed under
  • Heller's disease or syndrome
  • Dementia › infantile, infantilis (degenerative (primary)) (persisting) (unspecified severity) (without behavioral disturbance, psychotic disturbance, mood disturbance, and anxiety)
  • Disorder › childhood disintegrative NEC (of)
  • Disorder › disintegrative, childhood NEC (of)
  • Psychosis, psychotic › disintegrative

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