mrcem2-0492

mrcem2-0492

A 45-year-old man presents to the Emergency Department acutely unwell with abdominal and lower limb pain. He had a syncopal episode in the department and was moved into the resuscitation area. He had been taking prednisolone for temporal arteritis until recently when he had suddenly stopped them. His observations are as follows: temperature 38.9°C, HR 119, BP 79/42, Sats 98% on high flow oxygen, GCS 14/15, BM 1.4.
His initial blood results are shown below:
Na+: 114 mmol/l
K+: 7.1 mmol/l
Urea: 17.6 mmol/l
Creatinine: 150 mmol/l
What is the SINGLE most likely diagnosis?