Diagnostic Criteria

No consensus clinical diagnostic criteria for CHD8-related neurodevelopmental disorder with overgrowth (CHD8-NDD) have been published.

Suggestive Findings

CHD8-NDD should be considered in individuals with the following clinical and family history findings.

Clinical findings

• Developmental delay (DD) and/or intellectual disability (ID) (typically in the mild-to-moderate range)

• Neuropsychiatric disorders, including autism spectrum disorder (ASD)

• Generalized overgrowth, including tall stature and macrocephaly

• Sleep disturbance

• Gastrointestinal problems, especially constipation

Source: GeneReviews — "CHD8-Related Neurodevelopmental Disorder with Overgrowth"

Differential Diagnosis

Overgrowth conditions of interest in the differential diagnosis of CHD8-related neurodevelopmental disorder with overgrowth (CHD8-NDD) are summarized in . Table 3. Overgrowth Conditions to Consider in the Differential Diagnosis of CHD8-Related Neurodevelopmental Disorder with Overgrowth

Management Guidelines

No clinical practice guidelines for CHD8-related neurodevelopmental disorder with overgrowth (CHD8-NDD) have been published. Evaluations Following Initial Diagnosis To establish the extent of disease and needs in an individual diagnosed with CHD8-NDD, the evaluations summarized (if not performed as part of the evaluation that led to diagnosis) are recommended. Table 4. Recommended Evaluations Following Initial Diagnosis in Individuals with CHD8-Related Neurodevelopmental Disorder with Overgrowth

Source: GeneReviews — "CHD8-Related Neurodevelopmental Disorder with Overgrowth"

Surveillance Guidelines

To monitor existing manifestations, the individual's response to supportive care, and the emergence of new manifestations, the following evaluations are recommended.

Table 6.

Recommended Surveillance for Individuals with CHD8-Related Neurodevelopmental Disorder with Overgrowth

System/Concern | Evaluation | Frequency

Constitutional

| Measurement of growth parameters incl head circumference | At each visit1

Development

| Monitor developmental progress educational needs.

Psychiatric/

Behavioral

| Monitor for signs/symptoms of anxiety, psychosis, ASD, ADHD, aggressive or self-injurious behavior.

Neurologic

| Monitor those w/seizures as clinically indicated.

Assess for new manifestations such as seizures; changes in tone/movement disorders; signs/symptoms of CSF obstruction,2 compression of brain stem, cerebellum, or cranial nerves,3 or spinal cord dysfunction.4

Consider serial imaging for asymptomatic or minimally symptomatic Chiari I malformation detected previously.5 | As clinically indicated

Sleep

| Screening for signs/symptoms of sleep disturbance | At each visit

Gastrointestinal

| Monitor for signs/symptoms of constipation feeding issues.

Family/

Community

| Assess family need for social work support (e.g., palliative/respite care, home nursing, other local resources) care coordination.

ADHD = attention-deficit/hyperactivity disorder; ASD = autism spectrum disorder

1. Head circumference should be measured until adulthood.

2. For example, valsalva-induced occipital headache or cervical pain

Source: GeneReviews — "CHD8-Related Neurodevelopmental Disorder with Overgrowth"