Lab Case 73 – Interpretation

27 year old with weakness presents with…


metabolic – very high HCO3

Respiratory compensation is adequate  (expected CO2 48, actual 52)

normal anion gap

severe hpokalaemia and moderate hypochloraemia

Normal glucose and lactate


Compenasted metabolic alkalosis with severe hypokalaemia and moderate hypochloraemia

Causes to consider include:

Severe vomitting/ diarrhoea with dehydration (lacate normal)

Endocrine disorders – Conn’s (hypokalaemia, but sodium normal) or Cushing’s (usually hyperkalaemic)

Liqourice/ diuretic intoxication/ abuse

antacid/ alkali abuse

Other – unlikely in this patient – refeeding syndromes, post hyperventilation

2. ECG changes – see John’s blog from this week (29/9/15)

hypokalaemia is an ischaemia mimic

Note the ST depression, down up T waves

prominent U waves