Mechanisms in hypokalemia: clinical correlation.

Hypokalemia is seen most often with the use of diuretics and in patients with emesis. Other common clinical settings in which it may be significant include corticosteroid therapy, antibiotic usage, diarrhea, diabetic ketoacidosis, or psychiatric illness. Occasionally the cause may be obscure. In such situations the determination of urine potassium and arterial pH may prove helpful. Subclassification of hypokalemia into such categories as "acidosis", "alkalosis", "extra-renal", or "renal" loss is then possible. The cases discussed demonstrate the utilization of these methods to define the etiology and to understand the pathophysiology in hypokalemia.