Diagnostic criteria

Introduction

Autism is a subject that arouses both interest and concern in our modern society. Understanding, diagnosing and treating autism are challenges that require particular attention and expertise. France's Haute Autorité de Santé (HAS) plays a key role in shedding light on these issues, by providing detailed information and evidence-based guidelines. However, this information, although valuable, is often written in technical language and intended for an informed audience.

It is in this context that the present article finds its importance. The aim of this piece is to make the information presented by the HAS on autism and related disorders accessible to everyone. By translating this complex knowledge into more accessible terms, we aim to inform, educate and raise awareness among a wider audience, whether they are health professionals, educators, parents, or simply people interested in this topic.

Through this article, we will explore the diagnostic criteria for childhood autism, intervention methods, and other relevant topics, drawing on the work and recommendations of the HAS. Together, we will demystify a subject often reserved for specialists, by making this knowledge accessible to all.

The reference document for this article can be consulted here on the HAS website

2. Childhood Autism (F84.0)

a. Introduction to the disorder

Childhood autism, classified under code F84.0 in the ICD-10*, is a disorder that affects children from a very young age. It manifests through abnormalities or alterations in development, mainly in the areas of language, social interaction and play. Although this is a subject often reserved for specialists, we will demystify it by making this knowledge accessible to everyone.

b. Simplified diagnostic criteria

The diagnostic criteria for childhood autism can be summarised as follows:

• Developmental abnormalities: These abnormalities must be present before the age of 3 in at least one of the following areas:

1. Language (receptive or expressive) used in social communication.
2. Development of reciprocal social interaction.
3. Functional or symbolic play.

• Main symptoms: There must be at least six symptoms, including at least two in social interaction, and at least one in communication and in repetitive and stereotyped behaviours.
• Exclusions: The diagnosis must not be attributable to other disorders, such as early-onset schizophrenia or intellectual disability (Reference: Table 1, ICD-10).

c. Implications and care

Early identification and understanding of childhood autism are essential to offering appropriate care to the child. This care may include specialised therapies, educational support and close collaboration with families.

3. Atypical Autism (F84.1)

a. Introduction to the disorder

Atypical autism, identified under code F84.1 in the ICD-10, represents a particular form of autism spectrum disorder. Unlike typical childhood autism, it manifests from the age of 3 or later, or does not meet all the standard diagnostic criteria for autism. We will explore this often complex disorder, usually reserved for specialists, in a simple and understandable way.

b. Simplified diagnostic criteria

The diagnostic criteria for atypical autism fall into three main categories:

1. Atypicality in age of onset (F84.10):

• Developmental abnormalities visible from the age of 3 or later.
• Autism symptoms consistent with criteria B and C of autism (F84.0).

1. Atypicality in symptomatology (F84.11):

• Developmental abnormality visible before the age of 3.
• Partial autism symptoms, without fully meeting the criteria for typical autism (F84.0).

1. Atypicality in age of onset and symptomatology (F84.12):

• Developmental abnormalities visible only from the age of 3 or later.
• Partial autism symptoms, without fully meeting the criteria for typical autism (F84.0).

(Reference: Table 2, ICD-10)

c. Understanding the different atypicalities

Atypical autism can present unique challenges in diagnosis and care. The symptoms may resemble those of typical autism but manifest differently or at a different age. An accurate assessment and a deep understanding of these differences are essential to offering appropriate support to the individual.

d. Conclusion

Atypical autism illustrates the complexity and diversity of autism spectrum disorders. By demystifying this disorder and translating this knowledge into more accessible terms, we hope to contribute to a better understanding and to more empathetic and inclusive care for those affected by this disorder.

4. Rett Syndrome (F84.2)

a. Introduction to the disorder

Rett syndrome, referenced under code F84.2 in the ICD-10, is a rare neurological disorder that mainly affects girls. It is characterised by apparently normal development during the first months of life, followed by a sudden loss of manual skills and other severe symptoms. Understanding this syndrome can be difficult, but here we strive to present it in a simple and accessible way.

b. Simplified diagnostic criteria

The diagnostic criteria for Rett syndrome can be summarised as follows:

• Normal development at the start: Normal prenatal and perinatal period, normal psychomotor development up to 5 months.
• Deceleration of head growth: Between 5 months and 4 years.
• Loss of manual skills: Loss of purposeful functional hand skills acquired between 5 and 30 months.
• Impairment of language and psychomotor development: Severe impairment of language and severe psychomotor delay.
• Stereotyped hand movements: Appearance of stereotyped movements such as wringing or washing of the hands.
• Exclusions: The disorder must not be attributable to other specific disorders (Reference: Table 3, ICD-10).

c. Particularities and implications

Rett syndrome is particularly complex and requires multidisciplinary care. Affected children may need specialised therapies, adapted educational support and ongoing medical monitoring.

d. Conclusion

Rett syndrome illustrates the importance of an accurate diagnosis and a deep understanding of each autism spectrum disorder. By making this information accessible to a wider audience, we hope to contribute to better care and greater awareness of this rare but impactful syndrome.

5. Other Childhood Disintegrative Disorder (F84.3)

a. Introduction to the disorder

"Other childhood disintegrative disorder", classified under code F84.3 in the ICD-10, is a developmental disorder characterised by a marked loss of previously acquired skills after a period of apparently normal development. This disorder, less well known and often confused with others, deserves particular attention.

b. Simplified diagnostic criteria

The diagnostic criteria for this disorder are distinguished as follows:

• Normal development at the start: Normal development up to at least 2 years of age in communication, social relationships, play and adaptive behaviour.
• Marked loss of acquired skills: Clinically significant loss of acquired skills in at least two of the following areas:

1. Language, expressive or receptive.
2. Play.
3. Social skills or adaptive behaviour.
4. Bowel or bladder control.
5. Motor skills.

• Abnormal social functioning: Qualitative impairment of social functioning in at least two areas, such as reciprocal social interaction, communication and repetitive and stereotyped behaviours.
• Exclusions: The disorder must not be attributable to other varieties of pervasive developmental disorder, nor to other specific medical conditions (Reference: Table 4, ICD-10).

c. Understanding the loss of previously acquired skills

This disorder is particularly disconcerting because of the loss of previously acquired skills. This regression can be very stressful for families and requires specialised assessment and care.

d. Conclusion

"Other childhood disintegrative disorder" underlines the diversity and complexity of autism spectrum disorders. By demystifying this disorder and making it accessible to everyone, we contribute to better recognition and more effective care for affected children.

6. Asperger Syndrome (F84.5)

a. Introduction to the disorder

Asperger syndrome, classified under code F84.5 in the ICD-10, is an autism spectrum disorder characterised by an absence of general delay in language or cognitive development. It is distinguished by impairments in social interaction and restricted and repetitive interests or behaviours. Let us explore this unique disorder in a way that is understandable to everyone.

b. Simplified diagnostic criteria

The diagnostic criteria for Asperger syndrome can be summarised as follows:

• Absence of general delay: No clinically significant delay in language or cognitive development. Acquisition of single words before age 2 and use of communicative phrases before age 3.
• Impairment of social interaction: Presence of a qualitative impairment of reciprocal social interaction, similar to that observed in autism.
• Restricted interests and behaviours: Unusually intense and limited interests, or restricted, repetitive and stereotyped behaviours.
• Exclusions: The disorder must not be attributable to other specific disorders, such as simple schizophrenia or obsessive-compulsive disorder (Reference: Table 5, ICD-10).

c. Particularities and differences

Asperger syndrome is distinguished from other autism spectrum disorders by an absence of delay in language development. However, the challenges in social interaction and the restricted interests can have a significant impact on daily life.

d. Conclusion

Asperger syndrome, although less severe than other forms of autism, requires appropriate understanding and care. By making this information accessible, we hope to facilitate better recognition and more effective support for those living with this syndrome.

7. Conclusion

Autism and associated disorders are complex and often misunderstood subjects. This guide has attempted to break these disorders down into simple and accessible terms, drawing on the official diagnostic criteria of the ICD-10.

• Understanding diversity: Autism spectrum disorders are incredibly diverse, ranging from childhood autism to Asperger syndrome. Each disorder presents its own characteristics and challenges.
• Demystifying complexities: By translating this complex knowledge into more accessible terms, we have sought to make this information available not only to health professionals, but also to families, teachers and everyone seeking to understand these disorders.
• Towards better care: A better understanding of these disorders can lead to more empathetic and effective care, with an emphasis on individual needs and strengths.

In conclusion, it is important to recognise that this guide is not exhaustive and does not replace a professional assessment. However, by making this knowledge accessible to everyone, we hope to contribute to a more informed and inclusive society.

*The ICD-10, or International Classification of Diseases, 10th edition, is a medical coding system developed by the World Health Organization (WHO). It is used worldwide to classify and code diseases and other health problems.