Diagnostic Criteria

No consensus clinical diagnostic criteria for TET3-related Beck-Fahrner syndrome (TET3-BEFAHRS) have been published.

Suggestive Findings

TET3-BEFAHRS should be considered in individuals with the following clinical findings.

Clinical findings

• Mild-to-severe developmental delay or intellectual disability

AND

Source: GeneReviews — "TET3-Related Beck-Fahrner Syndrome"

Differential Diagnosis

Although there is significant phenotypic overlap with other mendelian disorders of the epigenetic machinery (also called chromatin-modifying disorders or chromatinopathies; see ), the clinical presentation of TET3-related Beck-Fahrner syndrome (TET3-BEFAHRS) is typically nonspecific global developmental delay and, consequently, all disorders associated with intellectual disability without other distinctive findings should be considered in the differential diagnosis. See OMIM Autosomal Dominant, Autosomal Recessive, Nonsyndromic X-Linked, and Syndromic X-Linked Intellectual Developmental Disorder Phenotypic Series.

Table 3.

Selected Chromatin-Modifying Disorders of Interest in the Differential Diagnosis of TET3-Related Beck-Fahrner Syndrome

Gene | Disorder | MOI | Clinical Characteristics

ASXL3

...

Source: GeneReviews — "TET3-Related Beck-Fahrner Syndrome"

Management Guidelines

No clinical practice guidelines for TET3-related Beck-Fahrner syndrome (TET3-BEFAHRS) have been published. Evaluations Following Initial Diagnosis To establish the extent of disease and needs in an individual diagnosed with TET3-BEFAHRS, the evaluations summarized (if not performed as part of the evaluation that led to the diagnosis) are recommended. Table 4. TET3-Related Beck-Fahrner Syndrome: Recommended Evaluations

Source: GeneReviews — "TET3-Related Beck-Fahrner Syndrome"

Surveillance Guidelines

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

Table 6.

TET3-Related Beck-Fahrner Syndrome: Recommended Surveillance

System/Concern | Evaluation | Frequency

Growth/Feeding

| • Measurement of growth parameters, incl weight, length/height, head circumference

• Eval of nutritional status safety of oral intake

| At each visit

Neurologic

| Monitor those w/seizures as clinically indicated.

Assess for new manifestations such as seizures, changes in tone, movement disorders.

Development

| Monitor developmental progress educational needs.

Neurobehavioral/

Psychiatric

| Assessment for anxiety, ADHD, ASD, aggression, self-injury

Gastrointestinal

| Assess for signs symptoms of constipation.

Family/Community

| Assess family need for social work support (e.g., palliative/respite care, home nursing, other local resources), care coordination, or follow-up genetic counseling if new questions arise (e.g., family planning).

Musculoskeletal

| Physical medicine, OT/PT assessment of mobility, self-help skills; clinical eval for joint hypermobility

Clinical eval for kyphosis /or scoliosis

Eyes | Complete ophthalmology eval | At least annually

Hearing

| Audiology eval

OT = occupational therapy; PT = physical therapy

Source: GeneReviews — "TET3-Related Beck-Fahrner Syndrome"