Flank pain and blood in the urine in a 49-year-old: a nephrology case to work up

Why flank pain with blood in the urine matters

Visible blood in the urine in an adult always needs explaining, because one of the causes is cancer of the kidney or bladder. Flank pain, high blood pressure and what you can feel in the abdomen narrow the field quickly.

What to ask in the history

• The pain: where, how it started, colicky or constant, radiation to the groin, how often it recurs
• The blood: throughout the stream or only at the start or end, clots
• Fever, burning on passing urine, frequency
• Previous kidney stones or urinary infections
• Headaches, high blood pressure, how long it has been known
• Family history of kidney disease, dialysis, brain haemorrhage or sudden death
• Painkillers (NSAIDs), smoking, weight loss

Red flags

• Fever with flank pain (an infected or obstructed kidney)
• Falling urine output or rising creatinine
• Clots or heavy bleeding
• Weight loss
• A sudden, severe headache
• Very high blood pressure

What to examine

• Blood pressure
• Abdomen: palpate each kidney with two hands (ballotable?), liver size
• Flank (renal angle) tenderness
• Heart murmurs
• Oedema, signs of anaemia or uraemia

First investigations

• Urinalysis and urine microscopy (red cells, casts, protein)
• Urine culture
• Serum creatinine, urea and electrolytes; full blood count
• Ultrasound of the kidneys and urinary tract
• CT (urography or non-contrast for stones) depending on the ultrasound

Differential diagnosis of flank pain with blood in the urine

Grouped, not ranked. Which one fits this patient is for you to work out in the case.

Common mistakes

• Calling every haematuria a stone or infection without imaging.
• Not asking about the family. Several kidney diseases are inherited, and the family history is often the clue.
• Ignoring the blood pressure, which can be a cause, a consequence or both.