Haematuria: diagnostic approach — formative SAQs

SAQ 1 — The school-age child with cola-coloured urine (10 marks, 15 minutes)

A 7-year-old boy presents with cola-coloured urine, peri-orbital swelling and a headache. His blood pressure is at the ninety-fifth centile for his age, sex and height. Two weeks earlier he had a febrile sore throat. The urine dipstick is positive for blood and protein, and microscopy shows red-cell casts and dysmorphic red cells. ^[8]

a) State the most likely diagnosis, and explain how the timing and the urine findings distinguish it from IgA nephropathy. (3 marks) ^{[8] [6]}

b) Give the expected complement pattern and the single serological test that supports the diagnosis, and state when the complement should normalise. (3 marks) ^{[8] [7]}

c) Outline your immediate management, including the approach to his blood pressure and fluid status. (4 marks) ^[8]