Differential diagnosis of hyperkalemia: an update to a complex problem

Abstract

Hyperkalemia is a relative common and sometimes life threatening electorlyte disorder. Although its symptomatic treatment is relatively easy, since precise therapeutic algorithms are available, its differential diagnosis is more complicated. The present review aims to unfold the differential diagnosis of hypekalemia using a pathophysiological, albeit clinically useful, approach. The basic elements of potassium homeostasis are provided, the causes of hyperkalemia are categorized and analysed and finally the required for the diferrential diagnosis laboratory tests are mentioned.

Keywords: hyperkalemia; potassium excresion; potassium homeostasis; potassium intake; pottasium shift.

Figure 1. Potassium, through its role in resting and action membrane potential, is of cardinal importance for the function of excitable tissues.

Figure 2. The principal cells and the potassium excretion in the cortical collecting duct.

Figure 3. The differential diagnosis of hyperkalemia.