31st July 2023

A 65-year-old man presents to an outpatient clinic complaining of several months of episodic bilateral loin pain radiating to the groin

A 65-year-old man presents to an outpatient clinic complaining of several months of episodic bilateral loin pain radiating to the groin, dysuria, and urgency. He also reports a recent episode of haematuria. Blood tests show a serum calcium level of 2.4 mmol/L, uric acid 356 umol/L and creatinine 88 umol/L. Urinalysis showed a urine pH of 8.0 and coffin lid crystals on microscopy. Urinalysis is also positive for blood, leukocytes and nitrites.

What is the likely aetiology?

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