mrcem2-0528

mrcem2-0528

A 72 year old male is brought into the emergency department by his wife with increasing fatigue, weakness and confusion over the past week. You note the patient takes metformin for type 2 diabetes mellitus. The patient’s observations and initial tests are shown below:

Blood pressure 96/60 mmHg
Pulse 114 bpm
Respiration rate 22 bpm
Oxygen saturations 96% on air
Na+ 147 mmol/l
K+ 5.6 mmol/l
Urea 21 mmol/l
Creatinine 132 µmol/l
Glucose 32 mmol/l
pH 7.33
Bicarbonate 19 mmol/l
Ketones 2 mmol/l

What is the most likely diagnosis?