MSRA-2425
A 56-year-old man presents to the Emergency Department with nausea and vomiting, with associated lethargy. He has mild asthma which is well controlled with a steroid inhaler but has no other medical history of note. He does not smoke but drinks up to 30 units of alcohol a week, mostly on the weekends.
Observations are as follows: Temperature is 37.2 oC, blood pressure is 108/68 mmHg, heart rate is 92 bpm and regular.
On examination, the patient appears to be clinically dehydrated, but there are no other abnormalities noted.
Investigations reveal the following:
Investigation Result Normal Values
Haemoglobin (Hb) 145 g/l 135–175 g/l
White cell count (WCC) 8.2 × 109/l 4.0–11.0 × 109/l
Urea 9.2 mmol/l 2.5–6.5 mmol/l
Creatinine (Cr) 178 µmol/l
(bloods carried out one year
previously showed a creatinine
of 76) 50–120 µmol/l
Potassium (K+) 4.9 mmol/l 3.5–5.0 mmol/l
Sodium (Na+) 131 mmol/l 135–145 mmol/l
Which of the following is most suggestive of acute kidney injury rather than chronic renal failure?