Table 4.

Recommended Evaluations Following Initial Diagnosis in Individuals with Squalene Synthase Deficiency

System/ConcernEvaluationComment
Neurologic Neurologic eval
  • To incl brain MRI
  • Consider EEG if seizures are a concern.
Development Developmental assessment
  • To incl motor, adaptive, cognitive & speech-language eval
  • Eval for early intervention / special education
Psychiatric/
Behavioral 		Neuropsychiatric evalIn persons age >12 mos: screen for presence of behavior issues incl sleep disturbances &/or findings suggestive of ASD.
Eyes Ophthalmologic evalTo assess for ↓ vision & optic nerve hypoplasia
Hearing Audiologic evalTo assess for hearing loss 1
Cardiovascular Clinical cardiac eval, w/consideration of echocardiogramTo assess for congenital structural cardiac lesions
Respiratory Consider sleep study.If sleep initiation & maintenance are an issue
Gastrointestinal/
Feeding 		Assess for neonatal hepatitis incl bilirubin concentrations (total, conjugated & unconjugated) & liver enzymes.In neonates
Gastroenterology / nutrition / feeding team eval
  • To incl eval of aspiration risk, nutritional status, & for constipation
  • Consider eval for gastrostomy tube placement in those w/failure to thrive, dysphagia, &/or aspiration risk.
Genitourinary Genitourinary eval for cryptorchidism & hypospadias in malesConsider US to assess for structural renal defects if external anomalies of the genitalia are present. 2
Musculoskeletal Orthopedics / physical medicine & rehab / PT/OT evalTo incl assessment of:
  • Gross motor & fine motor skills
  • Contractures
  • Mobility & activities of daily living & need for adaptive devices
  • Need for PT (to improve gross motor skills) &/or OT (to improve fine motor skills)
Integument Complete skin evalAssess for history of photosensitivity & sunburn when exposed to UV light.
Endocrine Endocrine assessmentConsider investigating anterior & posterior pituitary function if optic nerve hypoplasia is present.
Miscellaneous/
Other 		Consultation w/clinical geneticist &/or genetic counselorTo incl genetic counseling
Family supports & resourcesAssess need for:

ASD = autism spectrum disorder; OT = occupational therapy; PT = physical therapy; US = ultrasound

1.

Hearing loss has not been described as a primary feature in this condition; however, this recommendation is based on the fact that the affected individuals have intellectual impairment, which makes clinical assessment for hearing loss difficult.

2.

No structural renal anomalies have as yet been described in affected individuals.

From: Squalene Synthase Deficiency

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