High transtubular grandient hypokalemia: clinical case and a practical proposal for its approach

Abstract

Potassium is a predominantly intracelular ion involved in multiple essential functions to maintain celular homeostasis. Therefore, its variations at the plasma level are tightly regulated by the renal and endocrine systems; in addition to being affected by situations such as acidosis, changes in plasma osmolality and concentration of another electrolytes. Hypokalemia is a common electrolyte disorder in clinical practice affected by reporting excessive damage or loss. Its diagnostic approach requires a complete medical history that includes personal pathological and pharmacological history, a specific physical examination with certain conditions like patient´s blood volume and hydration status, as well as the measurement of other electrolytes at the plasma level and occasionally in urine. The thanstubuar potassium gradient is a useful tool to address posible causes. Bartter síndrome is one of the causes of elevated transtubular gradient hypokalemia.