Haematuria: diagnostic approach — branching viva

Opening — framing the problem

The examiner begins: a 7-year-old boy passes cola-coloured urine, has peri-orbital swelling and a blood pressure at the ninety-fifth centile, two weeks after a sore throat. What is your first framework for thinking about this? ^[8]

My first framework is the glomerular versus non-glomerular split, read from the colour of the urine and the cells it carries. Cola-coloured urine with red-cell casts, dysmorphic red cells and proteinuria points to a glomerular source, and the one to three week latency after a streptococcal throat infection points specifically to post-streptococcal glomerulonephritis. Before any blood test I confirm he is not in a hypertensive emergency, because his blood pressure is already at the limit and a nephritic child can deteriorate quickly. ^{[8] [1]}