Developmental regression — formative SAQs

SAQ 1 (10 marks)

A 22-month-old previously used several words and pointed to request. For 3 months he has been silent, with reduced social engagement. He walks well and is afebrile. [1] [7]

1. Define developmental regression and distinguish it from delay. (3) [1]
2. Outline your bedside assessment priorities. (4) [1] [3]
3. List immediate actions and referrals while awaiting specialist review. (3) [1] [14] [17]

Model answer

Regression is loss of a previously acquired skill; delay is failure to acquire skills on time. [1] Confirm a skill ledger with examples and tempo; examine neurology and head growth; assess seizures, hearing/vision access, safeguarding and caregiver concern. [1] [3] Arrange urgent hearing assessment and developmental/neurology pathways as indicated; start interim supports; name owners for results; safety-net further loss, seizures and reduced alertness. [1] [14] [17]

SAQ 2 (10 marks)

A 15-month-old girl has lost purposeful hand use, developed continuous hand wringing, and uses fewer social vocalisations. Head circumference velocity has slowed. [6]

1. What phenotype are you considering and why is wait-and-see unsafe? (3) [6]
2. What history and examination features support this pathway? (3) [6]
3. How would you counsel the family about next steps and uncertainty? (4) [3] [9] [14]

Model answer

Classic Rett-window phenotype: regression after early development with loss of purposeful hand use and hand stereotypies; delayed evaluation risks missed diagnosis and supports. [6] Document early typical skills, age at loss, stereotypies, communication fall, head-growth trajectory and neurological exam. [6] Explain concern in plain language, arrange neurology/genetics evaluation, start supports now, avoid false certainty, and close referral loops; do not hide progressive disease under a premature behaviour label. [3] [9] [14]