Clinical Guidance

No clear genotype-phenotype correlations are known.

Source: GeneReviews — "VPS13D Movement Disorder"

Diagnostic Criteria

Suggestive Findings

VPS13D movement disorder should be suspected in individuals with the following clinical, laboratory, and imaging findings.

Clinical presentation

• Infantile-onset hypotonia and severe developmental delay or motor delay that progresses to severe generalized dystonia or spastic ataxia

• Childhood-onset chorea or dystonia

• Early-adulthood-onset progressive spastic ataxia, dystonia, and myoclonus

Additional clinical features

• Macro-saccadic intrusions; these large abnormal back-and-forth eye movements with stationary inter-saccadic intervals are often triggered by saccades.

• Pyramidal signs (e.g., hyperreflexia, Babinski signs)

• Peripheral axonal neuropathy

• Seizures

Laboratory findings

Source: GeneReviews — "VPS13D Movement Disorder"

Differential Diagnosis

Table 2. Disorders to Consider in the Differential Diagnosis of VPS13D Movement Disorder

Management Guidelines

Evaluations Following Initial Diagnosis To establish the extent of disease and needs in an individual diagnosed with VPS13D movement disorder, the evaluations summarized (if not performed as part of the evaluation that led to the diagnosis) are recommended. Table 3. Recommended Evaluations Following Initial Diagnosis in Individuals with VPS13D Movement Disorder

Source: GeneReviews — "VPS13D Movement Disorder"

Clinical Guidance

No specific agents or circumstances are to be avoided aside from excessive alcohol use, which could worsen ataxia.

Source: GeneReviews — "VPS13D Movement Disorder"

Therapies Under Investigation

Studies are currently under way to understand the role of VPS13D in mitochondrial integrity and ultimately develop targeted treatments that can enhance mitochondrial function. Search ClinicalTrials.gov in the US and EU Clinical Trials Register in Europe for access to information on clinical studies for a wide range of diseases and conditions. Note: There may not be clinical trials for this disorder.

Source: GeneReviews — "VPS13D Movement Disorder"

Surveillance Guidelines

No specific surveillance guidelines exist. The authors recommend following standard ataxia and spasticity guidelines. Care should include regular visits to a neurologist and physiatrist. A speech therapist and a urologist should be consulted when indicated.

Table 4.

Recommended Surveillance for Individuals with VPS13D Movement Disorder

System/Concern | Evaluation

Genitourinary

| Ask about urinary urgency.

Musculoskeletal

| Monitor contractures.

Neurologic

| Monitor those w/seizures as clinically indicated; evaluate fall risk gait stability.

Miscellaneous/Other

| Monitor developmental progress educational needs.

Source: GeneReviews — "VPS13D Movement Disorder"