Haematuria: diagnostic approach — structured clinical encounter

Station 1 — recognition

The examiner asks what worries me about this child and how I frame the problem. I explain that cola-coloured urine with red-cell casts, dysmorphic red cells and proteinuria points to a glomerular source, and that the one to three week latency after a streptococcal throat infection points specifically to post-streptococcal glomerulonephritis. I confirm first that he is not in a hypertensive emergency, because his blood pressure is already at the limit and a nephritic child can deteriorate. I note that the colour and the cells together anchor the source before a single blood test returns. [8] [1]

Station 2 — resuscitation and assessment

Asked what I do first, I reassess his airway, breathing and circulation, and judge the haemodynamic and fluid status from his perfusion and his oedema. Because he is nephritic rather than dehydrated, I expect fluid overload, so I restrict fluids and salt and prepare a diuretic for overload. His blood pressure is at the ninety-fifth centile, so I control it with a titratable antihypertensive infusion under monitoring, avoiding an abrupt fall that could cause neurological injury, and I warn the nephrology and intensive care teams early. [8]

Station 3 — investigation

Asked how I confirm the diagnosis, I send a complement C3 and C4 and streptococcal serology. I expect a low C3 with a normal C4 and raised anti-streptolysin O and anti-DNase B titres, consistent with post-streptococcal glomerulonephritis. I send renal function, albumin and a full blood count as baseline, and I contrast this with IgA nephropathy, which gives synpharyngitic cola urine with a normal complement, and with lupus nephritis, which drops both C3 and C4. I note that his C3 should normalise within six to eight weeks if the diagnosis is correct. [8] [7]

Station 4 — definitive care

The diagnosis of post-streptococcal glomerulonephritis is confirmed. Asked about the treatment, I describe supportive management: fluid and salt balance, blood pressure control, diuretics for overload, and antibiotic clearance of the group A streptococcus to prevent spread. I explain that the disease is usually self-limited and the long-term outlook is excellent, so I do not start immunosuppression. I contrast this with the nephrology-led management of IgA nephropathy, where renin-angiotensin blockade is used for proteinuria and immunosuppression is reserved for high-risk disease. [8] [6]

Station 5 — disposition and family

Finally I address disposition and safety-netting. This child needs paediatric nephrology involvement and admission for management of his hypertension and fluid status, and from a regional hospital I continue treatment during retrieval. I counsel the family that post-streptococcal glomerulonephritis usually resolves completely, with the complement recovering within six to eight weeks, and I give a clear safety-net: return for worsening swelling, headache, reduced urine output or breathlessness. I make sure every clinician who later sees a child with haematuria holds the same rule of confirming blood with microscopy, measuring the blood pressure, and escalating for the red flags. [8] [1]