Psychiatry · Year 2 · from Psychiatry
Case 2: Autism Spectrum Disorder
Patient Presentation
Demographics: 3-year-old male
Chief Complaint: "He doesn't talk and doesn't play with other kids."
History of Present Illness: A 3-year-old boy is referred by his pediatrician after failing the M-CHAT-R/F screening at his 24-month well-child visit. His parents had noticed he was "different" from his older sister at the same age but hoped he would "catch up." He has approximately 10 single words but does not combine words into phrases. He rarely uses words communicatively - mostly labels objects. He does not point to show things to his parents and does not follow a point when they try to show him something. He makes limited eye contact, often looking past people rather than at their faces. He does not respond to his name consistently - parents initially thought he might be deaf, but hearing test was normal. He prefers to play alone, lining up his toy cars in precise rows for extended periods. If someone moves his cars, he becomes extremely distressed and has prolonged tantrums (30-60 minutes). He is fascinated by spinning wheels and will spin the wheels of toy cars while lying on his side watching them for long periods. He flaps his hands when excited. He is very particular about food textures - only eats smooth, pureed foods and gags on anything with lumps. He becomes upset with changes in routine - if they take a different route to grandmother's house, he cries the entire way. He does not engage in pretend play - does not feed dolls or pretend a block is a phone.
Developmental History:
- Full-term, uncomplicated pregnancy and delivery
- Motor milestones: Sat at 6 months, walked at 14 months (normal)
- Language: Babbled normally, first words around 12 months, but language seemed to plateau
- Social: Parents note he "never really reached for us to be picked up" as a baby
- Regression: Parents uncertain - "He may have lost a few words around 18 months"
Family History: Maternal cousin with autism, father describes himself as "socially awkward"
Physical Examination:
- Growth parameters: Normal
- Dysmorphic features: None
- Neurological: Normal tone, no focal deficits
- Head circumference: 75th percentile (macrocephaly noted)
Behavioral Observations During Assessment:
- Limited eye contact with examiner
- Did not respond to name despite 5 attempts
- No joint attention - did not look where examiner pointed
- Lined up toys meticulously, became distressed when examiner moved one
- Hand flapping observed when excited
- No spontaneous vocalizations directed at people
- Explored room by running along walls, did not interact with examiner or mother
Diagnostic Assessment:
- M-CHAT-R/F: Positive (failed at 24 months)
- ADOS-2 (Module 1): Total score 18 (autism cutoff = 11), classification: Autism
- ADI-R: Exceeds diagnostic threshold for ASD
- Developmental Assessment (Bayley-III):
- Cognitive: 75 (borderline)
- Language: 60 (delayed)
- Motor: 85 (low average)
- Audiological evaluation: Normal hearing
Diagnosis: Autism Spectrum Disorder, Level 2 (requiring substantial support), with accompanying language impairment and without intellectual impairment
Treatment:
- Early intervention referral for intensive services:
- Applied Behavior Analysis (ABA) - 25 hours/week recommended
- Speech-language therapy - 3 sessions/week
- Occupational therapy for sensory processing - 2 sessions/week
- Parent training in ABA principles
- Special education evaluation for IEP when entering school
- Visual schedules at home to help with transitions
- Social stories for routine changes
- Referral to developmental pediatrician for coordination of care
- At 6-month follow-up:
- Now using 50+ words and some 2-word combinations
- Beginning to point to request (protoimperative pointing)
- Tolerates brief interactions with therapists
- Tantrums reduced with visual schedules and preparation for transitions
- Parents report improved ability to manage behaviors
- Sleep remains problematic - started melatonin 1 mg at bedtime with improvement
Clinical Pearl: ASD diagnosis requires deficits in all three areas of social communication (reciprocity, nonverbal communication, relationships) PLUS at least 2 of 4 types of restricted/repetitive behaviors. Early identification through screening at 18 and 24 months allows for early intervention, which has the best evidence for improving outcomes. The M-CHAT-R/F is the standard screening tool. ADOS-2 is the gold-standard diagnostic observation. ABA is the most evidence-based intervention. No medication treats core ASD features - medications target associated symptoms like irritability (risperidone, aripiprazole), ADHD symptoms (stimulants), anxiety (SSRIs), or sleep (melatonin). ASD has ~90% heritability - recurrence risk in siblings is 10-20%.
Clinical Image
Image Description: Educational diagram showing the dopaminergic pathways of the brain relevant to ADHD, illustrating the mesocortical pathway (prefrontal cortex involvement in attention and executive function), mesolimbic pathway (reward processing), and nigrostriatal pathway (motor control). Highlights the prefrontal cortex hypofunction and dopamine/norepinephrine signaling deficits associated with ADHD.
Attribution: Educational diagram of dopaminergic pathways relevant to ADHD neurobiology. Wikimedia Commons, CC BY-SA 4.0.
Image Source: Adapted from Wikimedia Commons dopaminergic pathways diagram for educational purposes.