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]