Abstract: PO1470
An Interesting Case of Hypokalemia
Session Information
- Fluid, Electrolyte, and Acid-Base Disorders: Clinical - 1
October 22, 2020 | Location: On-Demand
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Report
- 902 Fluid, Electrolyte, and Acid-Base Disorders: Clinical
Authors
- Ghaffar, Adil, University of Wisconsin System, Madison, Wisconsin, United States
- Singh, Tripti, University of Wisconsin System, Madison, Wisconsin, United States
Introduction
Hypokalemia (serum potassium <3.5 meq/L) is one of the most common abnormalities encountered in nephrology practice. With careful history and laboratory investigations, the cause can usually be found.
Case Description
A 68-year-old caucasian male with Hypertension was referred for hypokalemia with level of 2.1 meq/L, serum bicarbonate was 27 meq/L and serum magnesium was 1.7meq/L. His antihypertensives were lisinopril 40mg and chlorthalidone 25mg daily. Despite discontinuation of chlorthalidone, he still required 120 meq of potassium chloride ER tablets daily with potassium levels at 2.8 to 3 meq/L. 24 hr urine potassium was 51 meq/L, denoting renal potassium wasting. Serum cortisol and ACTH levels were normal. Serum aldosterone level was <3 ng/dl and renin activity was 0.1 ng/ml/hr. Upon further exploration, he reported use of licorice for few months. He was advised to stop its use with subsequent improvement of potassium levels to above 4 meq/L and a reduction in potassium repletion.
Discussion
The causes for hypokalemia with hypertension and renal potassium wasting can be differentiated with serum aldosterone, renin activity and cortisol levels. In primary hyperaldosteronism, serum aldosterone is elevated and renin activity suppressed whereas in secondary form, both are elevated. When both are suppressed, it denotes either apparent mineralocorticoid excess, Liddle syndrome, cortisol excess or licorice use. Our patient had normal cortisol level, presented late in adulthood excluding Liddle syndrome and apparent mineralocorticoid excess, and making licorice as a likely cause. He had been chewing black licorice for its taste.
Licorice was used in the past for gastric ulcers but it is rarely used nowadays. It inhibits the conversion of cortisol into inactive cortisone, allowing cortisol to act on the mineralocorticoid receptor. The use of licorice should be explored, whenever one encounters renal potassium wasting with suppressed renin and aldosterone.