Specimen Name Result Units Range
Plasma Sodium 115 mmol/L (135-145)
Potassium 7.6 mmol/L (3.5-5.5)
Chloride 85 mmol/L (100-109)
Bicarbonate 20 mmol/L (22-32)
Glucose 6.5 mmol/L (3.8-5.5)
Urea 19.0 mmol/L (2.7-7.2)
Creatinine 130 μmol/L (60-110)

55yo male with history of long-standing hypertension.
Rx Potassium Sparing Diuretics

Associated pre-renal azotaemia

Causes of hyponatraemia & hyperkalaemia (Na+:K+ ratio < 25:1):

  • Addison's - hypo-osmolar, mild uraemia
  • K+-sparing diuretics
  • DKA - hyper-osmolar, hyperglycaemia
  • Renal failure - esp. salt-losing nephritis, hypo-osmolar & uraemia
  • ACE Inhibitors (rarely)

Drugs Causes of hyponatraemia & hyperkalaemia:

  • diuretics - spironolactone, amiloride, triamterene
  • ACE inhibitors, Entresto®
  • PG inhibitors - indomethacin/NSAIDs
  • Other nephrotoxins