Hypokalaemia and hyperkalaemia

Disturbances in potassium homoeostasis presenting as low or high serum pota ssium are common, especially among hospitalised patients. Given the fact th at untreated hypokalaemia or hyperkalaemia is associated with high morbidit y and mortality, it is critical to recognise and treat these disorders prom ptly. In this article, normal potassium homoeostasis is reviewed initially and then a pathophysiological approach to work-up and management of hypokal aemia and hyperkalaemia is presented. Recent advances with respect to the r ole of kidney in handling of the potassium, the regulation of renal ion tra nsporters in hypokalaemia, and treatment of hypokalaemia and hyperkalaemia will be discussed.