A 30 year old ama presents with weakness and profound hypokalaemia

1.

Profound hypokalaemia requiring cardiac monitoring and K replacement (probably via central access)

Non anion gap metabolic acidosis with appropriate compensation

Raised CK – Rhabdomyolysis (seek cause – ??hypokalaemia related, immobilisation, other)

Normal renal function

Minimally elevated A-a gradient on 21% Oxygen

2. Causes:

Renal tubular acidosis – most likely cause

Normal Saline administration

Diarrhoea

Carbonic anhydrase inhibitors

Addison’s – unlikely with low K

Pancreatic, small bowel or ureteric fistula

3. Hypokalaemia

Unlikely due to high CK – not significant elevation

From Fellowship examination 2013.1