Excludes1 pair

F84.0 vs F84.3

F84.0 and F84.3 are not coded together. ICD-10-CM declares them mutually exclusive with an Excludes1 note — the two conditions are not expected to occur together, so exactly one of them is normally correct for a given encounter. The Official Guidelines carve out one exception: if the two conditions are clearly unrelated to each other, both may be reported.

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
  • Disorder › autistic
  • Disorder › autism spectrum
  • 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
  • Disorder › childhood disintegrative NEC
  • Disorder › disintegrative, childhood NEC
  • Psychosis, psychotic › disintegrative (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