Pediatric Endocrinology and Diabetes
Domain focus
Pediatric Endocrinology and Diabetes tests growth disorders, thyroid disease, puberty, adrenal disorders and diabetic ketoacidosis. DKA management is the highest-yield emergency topic.
Core rules
- Short stature: plot height and growth velocity, assess bone age, and screen for coeliac disease, hypothyroidism and IGF-1 deficiency before considering growth hormone.
- Congenital hypothyroidism is detected by newborn screening; early levothyroxine prevents intellectual disability.
- Type 1 diabetes presents with polyuria, polydipsia and weight loss; DKA adds vomiting, Kussmaul breathing and ketones.
- DKA: give isotonic saline for shock, then maintenance fluids; start insulin infusion after fluids; monitor potassium and neurological status. Do not give bicarbonate routinely.
- Adrenal crisis: give hydrocortisone immediately; do not wait for cortisol results.
Worked example
A 10-year-old with new diabetes has glucose 28 mmol/L, pH 7.10, bicarbonate 8 mmol/L and ketonuria. This is DKA. Give a 10 mL/kg 0.9% saline bolus, then maintenance fluid, start insulin infusion at 0.05–0.1 U/kg/hour, and replace potassium once urine output is confirmed. Monitor for cerebral oedema with headache, bradycardia or falling conscious level.
Traps
Giving a rapid large fluid bolus in DKA; starting insulin before fluids; forgetting potassium; using bicarbonate routinely; missing adrenal insufficiency in hyperpigmentation and hypotension.