Diagnostic Criteria

Suggestive Findings

SLC39A14 deficiency should be suspected in probands with typical clinical, neuroimaging, and laboratory findings : Clinical findings. Infantile or early-childhood onset of the following:

• Delay in acquisition of developmental motor milestones or loss of developmental motor milestones

• Progressive pharmaco-resistant dystonia

• Parkinsonism signs (tremor, bradykinesia, hypomimia)

• Bulbar dysfunction

• Dysarthria

Note: One individual with onset of dystonia during the second decade has been reported, suggesting that milder presentations with juvenile or adult onset may also occur . Neuroimaging. Brain MRI findings characteristic of manganese deposition including T1-weighted hyperintensity of the following:

Source: GeneReviews — "SLC39A14 Deficiency"

Differential Diagnosis

Table 2. Hereditary Disorders of Interest in the Differential Diagnosis of SLC39A14 Deficiency

Management Guidelines

Evaluations Following Initial Diagnosis To establish the extent of disease and needs in an individual diagnosed with SLC39A14 deficiency, 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 SLC39A14 Deficiency

Source: GeneReviews — "SLC39A14 Deficiency"

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 4.

Recommended Surveillance for Individuals with SLC39A14 Deficiency

System/Concern | Evaluation | Frequency

Feeding

| • Measurement of growth parameters

• Eval of nutritional status safety of oral intake

| At each visit

Neurologic

| • Monitor development incl ambulation speech.

• Neurologic exam (scoring of mvmt disorder severity)

To assess treatment response disease progression:

• Whole-blood manganese levels

• Brain MRI

| To be considered on an individual basis based on available resources

Source: GeneReviews — "SLC39A14 Deficiency"