F84.1 ICD-10-CA code: Atypical autism
F84.1 is the ICD-10-CA code for “Atypical autism” in CIHI’s FY 2026–2027 release, in effect from Apr 1, 2026.
Official description
F84.1Atypical autism
ICD-10-CA · Canada · Also written F841
Index terms
Entries in CIHI’s alphabetical index that lead to F84.1. Searching the index by the condition the note names is how coders reach this code.
- Psychosis, psychotic, childhood, atypical
- Psychosis, psychotic, infantile, atypical
- Retardation, mental, with, autistic features
- Autism, autistic (childhood) (infantile), atypical
Notes for F84.1
As CIHI prints them, with any note F84.1 takes from the headings above it.
Includes
- Atypical childhood psychosisMental retardation with autistic features
- Disorders of psychological developmentFrom Chapter 5: Mental and behavioural disorders (F00-F99)
Use additional code
Add a code for this detail when the note documents it.
- Use additional code (F70-F79) to identify mental retardation.
- Use additional code to identify any associated medical condition and mental retardation.From F84 Pervasive developmental disorders
Excludes
Conditions classified elsewhere.
- Symptoms, signs and abnormal clinical laboratory findings, not elsewhere classified (R00-R99)From Chapter 5: Mental and behavioural disorders (F00-F99)
Note
- A type of pervasive developmental disorder that differs from childhood autism either in age of onset or in failing to fulfil all three sets of diagnostic criteria. This subcategory should be used when there is abnormal and impaired development that is present only after age three years, and a lack of sufficient demonstrable abnormalities in one or two of the three areas of psychopathology required for the diagnosis of autism (namely, reciprocal social interactions, communication, and restricted, stereotyped, repetitive behaviour) in spite of characteristic abnormalities in the other area(s). Atypical autism arises most often in profoundly retarded individuals and in individuals with a severe specific developmental disorder of receptive language.
- A group of disorders characterized by qualitative abnormalities in reciprocal social interactions and in patterns of communication, and by a restricted, stereotyped, repetitive repertoire of interests and activities. These qualitative abnormalities are a pervasive feature of the individual's functioning in all situations.From F84 Pervasive developmental disorders
- The disorders included in this block have in common: (a) onset invariably during infancy or childhood; (b) impairment or delay in development of functions that are strongly related to biological maturation of the central nervous system; and (c) a steady course without remissions and relapses. In most cases, the functions affected include language, visuo-spatial skills, and motor coordination. Usually, the delay or impairment has been present from as early as it could be detected reliably and will diminish progressively as the child grows older, although milder deficits often remain in adult life.From F80-F89 Disorders of psychological development
Where F84.1 sits
- 1ChapterChapter 5: Mental and behavioural disorders (F00-F99)
- 2Block F80-F89Disorders of psychological development
- 3Category F84Pervasive developmental disorders
- 4Valid code F84.1Atypical autism
Source and release
- Data release
- ICD-10-CA · FY 2026–2027
- Effective date
- Apr 1, 2026
- Publisher
- CIHI
This page is built from the ICD-10-CA catalog that Vero Codes reads when it suggests codes: Canadian Institute for Health Information’s FY 2026–2027 release, imported from the publisher’s file and checked against it. The description, notes and structured data come from the same record.
Frequently asked questions
What does ICD-10-CA code F84.1 mean?
F84.1 is the ICD-10-CA code for “Atypical autism” in CIHI’s ICD-10-CA FY 2026–2027 release.
Where is F84.1 in ICD-10-CA?
F84.1 sits under F84 Pervasive developmental disorders, within F80-F89 Disorders of psychological development, within Chapter 5: Mental and behavioural disorders (F00-F99).
What coding notes apply to F84.1?
ICD-10-CA lists Note, Includes, Use additional code, Excludes notes for F84.1, including those from the headings it sits under. They are listed on this page with where each one comes from.
Which ICD-10-CA release does this page use?
It uses CIHI’s FY 2026–2027 release, in effect from Apr 1, 2026 to Mar 31, 2027. It is a reference: confirm the code against the current list and the payer’s rules before you submit it.