Down syndrome — formative SAQs

SAQ 1 (10)

A term newborn is noted on the postnatal ward to be hypotonic, with a flat facial profile, upslanting palpebral fissures, a single transverse palmar crease, and a wide sandal gap. A chromosomal microarray confirms additional material consistent with chromosome 21. [1] [2]

a) Define Down syndrome and state why a karyotype is required in addition to the microarray. (3 marks) [1]

b) Outline the newborn-period surveillance items, including the timing of the cardiac investigation. (3 marks) [2] [4]

c) The newborn develops bilious vomiting on day two. State the most likely diagnosis and your immediate management. (2 marks) [1]

d) A routine blood count at one week shows a blast excess. Explain what transient abnormal myelopoiesis is and the principle of its management. (2 marks) [3]

SAQ 2 (10)

A four-year-old boy with known Down syndrome is brought by his parents because his behaviour has deteriorated, his teacher reports poor concentration, and his mother has noticed loud snoring and restless sleep. He has not had a sleep study. [5] [2]

a) What is the most likely unifying diagnosis for the behavioural change, and what investigation confirms it? (3 marks) [5]

b) Explain why this complication is common in Down syndrome, naming the anatomical and physiological factors. (2 marks) [5] [1]

c) Outline the full annual surveillance schedule that this child should be receiving, beyond the sleep assessment. (3 marks) [2] [1]

d) The family asks whether he needs an x-ray of his neck because of Down syndrome. State the current recommendation on routine cervical spine imaging in asymptomatic children and give the reasoning. (2 marks) [2] [1]