AKT-3564

AKT-3564

A 51-year-old woman presents to her General Practitioner with polyuria. She has a history of multiple attendances and a previous neurology referral for headache.
On examination, her blood pressure is 150/90 mmHg. Dipstick urinalysis reveals haematuria. She commences a three-day course of trimethoprim. She returns, still complaining of symptoms, at which point the presence of normochromic normocytic anaemia is noted, along with a serum creatinine of 220 µmol/l (normal range: 50–120 µmol/l). A urine culture result shows no growth.
What diagnosis is most likely to explain her reduced renal function?