Developmental Delay and Autism Flashcards
What are the diagnostic approaches for developmental disabilities?
clinical genetics evaluation neuroimaging metabolic testing cytogenetics (chromosomes and FISH) cytogenomics (arrays) single gene NGS panels exome/whole genome sequencing
What are the parts of a clinical genetics evaluation for the diagnostic approaches for developmental delay?
family history: prenatal, birth, family, medical histories; onset and progression of delays; behavioral phenotypes (hyperactivity, autistic features, social interactions, strengths and weaknesses); other (pain sensitivity, appetite, sleep)
physical exam (growth, head size, dysmorphic features [face, hands, feet], birth defects, skin, organomegally, tone/movement deficits [neuro exam])
co-morbidities (vision loss and hearing loss)
other key findings
List the important findings on neuroimaging that may be suspicious for developmental delay.
MRI: corpus callosum ventriculomegaly cortical dysplasia increased subarachnoid spaces posterior fossa abnormalities CT: craniosynostosis/calcifications MRS: biochemical changes (decreased creatine in brain or absent creatine in brain) EEG: assessment of seizures/epilepsy
When is metabolic screening for developmental delay indicated?
when there is no NBS or limited screening regression of milestones FTT episodic decompensations consanguinity affected siblings associated neurological findings (seizures, ataxia, abnormal movement, etc.) *this is because it is low yield
What are they subtypes of Autism?
“complex”: more often ID, dysmorphisms, syndromic or chromosomal cause, negative fhx
“essential”: no dysmorphisms/anomalies, more often male, increased siblings risk, more often family history of autism/milder features
subset: with family history of alcoholims, psychiatric disorders, learning problems/MR
What are the ACMG recommendations for diagnosing autism?
clinical genetics evaluation (targeted testing as indicated or metabolic referral/testing) Microarray (10% yield) Fragile X- males only (1-5%) MECP2 in all females MECP2 duplications in males PTEN if HC >98%
