Hypertension in children — formative SAQs

SAQ 1 — Six-year-old with stage 2 hypertension at a school check (10 marks, 15 minutes)

A six-year-old boy has a blood pressure of 124/84 mmHg recorded at a school entry health check, well above the 95th percentile for his age, sex and height. On repeat measurement in your clinic two weeks later it is 122/82 mmHg. He is asymptomatic, on the 50th centile for weight, and has no family history of note. His urinalysis shows 2+ protein and 1+ blood, and his creatinine is at the upper limit of normal. A renal ultrasound shows a small left kidney with cortical thinning and an enlarged, normal right kidney. [1]

a) What is the correct diagnostic category of his blood pressure, and why is a single elevated reading not enough to label him hypertensive? Outline how you confirm the diagnosis. (3 marks) [1]

b) Given his age, his blood pressure category and his urinalysis, what is the most likely cause of his hypertension, and what does the ultrasound finding of a small scarred left kidney suggest about the underlying renal diagnosis? Name two further investigations you would request to define the cause and the target-organ status. (4 marks) [1] [4]

c) Outline your management plan, including the first-line drug class you would choose and the blood-pressure target you would aim for, and explain why an ACE inhibitor is particularly appropriate here. (3 marks) [1] [8]

SAQ 2 — Fourteen-year-old with primary hypertension and obesity (10 marks, 15 minutes)

A fourteen-year-old girl is referred after her general practitioner recorded a blood pressure of 138/88 mmHg at a routine visit. She is asymptomatic and on the 95th centile for weight with a body mass index of 31. Her father has hypertension and had a myocardial infarction at forty-five. Her four-limb blood pressures are equal with no radio-femoral delay, her urinalysis is normal, and her creatinine is normal. A 24-hour ambulatory blood pressure monitor shows a mean systolic pressure at the 97th percentile with a load of 55 per cent. An echocardiogram shows a left ventricular mass index at the 97th percentile. [1]

a) What is the diagnostic category of her ambulatory blood pressure study, and what does the ambulatory load of 55 per cent signify? Explain how the ambulatory study distinguishes her from a child with white-coat hypertension. (3 marks) [5] [3]

b) What is the significance of the echocardiographic finding for her management, and how does it change the threshold for starting drug therapy? Outline the lifestyle measures you would discuss with her. (4 marks) [1] [7]

c) Name two first-line drug classes appropriate for her, state the blood-pressure target you would aim for, and describe the monitoring she will need once drug therapy is started. (3 marks) [1] [8]