24th June 2026

Mr Davies is a 70-year-old gentleman who is currently an inpatient on a general medical ward being treated for staphylococcal infective endocarditis with flucloxacillin and gentamicin.

Mr Davies is a 70-year-old gentleman who is currently an inpatient on a general medical ward being treated for staphylococcal infective endocarditis with flucloxacillin and gentamicin. Three weeks into his treatment, he develops increasing nausea and fatigue, associated with mild abdominal discomfort. There is no evidence of a new murmur, his observations remain stable, and there is no evidence of peripheral oedema. Repeat blood tests show that his creatinine has doubled, and on review of his fluid balance, his urine output has reduced to 25ml/hour for the last 24 hours. His oral intake is approximately 1500ml/24hours. Urinalysis shows 1+ haematuria, 1+ proteinuria, and 2+ leucocytes. What complication has Mr Davies developed?

Select the SINGLE most appropriate option from the list below. Select ONE option only.