Case Report of a Patient Who Experienced Cardiovascular Collapse Secondary to Severe Hypokalemia from Chronic Consumption of Licorice-Containing Preserved Plums

Presentation Number: SAT-0762
Date of Presentation: June 21st, 2014

Melvin Kok Seng Lee* and Cherng Jye Seow
Tan Tock Seng Hospital, Singapore, Singapore

Abstract

Introduction:

Licorice is a known cause of hypokalemia. There are reports of life-threatening cardiac arrhythmias secondary to hypokalemia arising from excessive licorice intake. Not many are aware that licorice is an ingredient in preserved plums, a popular local snack. We report a patient who presented with cardiovascular collapse secondary to ventricular fibrillation from severe hypokalemia. She was successfully resuscitated, and subsequent history- taking and detailed biochemical investigation point towards chronic licorice ingestion as the most likely aetiology.

Case report:

A 66 year-old Chinese lady with no significant medical history of note presented with poor oral intake and worsening muscle cramps over a few days. She subsequently had a cardiac arrest. Cardiopulmonary resuscitation and defibrillation was initiated rapidly when ventricular fibrillation was noted. She  had no history of hypertension. On examination, she did not look Cushingnoid. Biochemical results: Sodium 135 mmol/L (RI: 134-145), Potassium 1.6 mmol/L (RI: 3.5-5.0), Magnesium 0.6 mmol/L (RI:0.7-1.0) fT4 19 pmol/L (RI:8-21), TSH 2.55 mIU/L (RI: 0.34-5.60), HCO3 29 mmol/L (RI: 19-31). Her spot urinary potassium was 20.9 mmol/L suggesting renal loss.  Both aldosterone and renin were low at 217 pmol/L and 0.37 ng/ml/hr respectively. 8am cortisol was suppressed at 45 nmol/L after an overnight 1mg dexamethasone suppression test. The hypokalemia was aggressively corrected and she underwent urgent cardiac catheterisation. This revealed sub-total occlusion (TIMI 1 Flow) of the left anterior descending artery. The cardiologist deemed the occlusion as an unlikely root cause of the cardiovascular collapse. A detailed history was taken from the patient and it surfaced that she had been taking a large amount of preserved plums for the last few years. Her poor oral intake prior to admission had likely exacerbated the hypokalemia resulting in ventricular fibrillation. She was advised to stop intake of preserved plums. Serum potassium rapidly normalised in the ward.

A follow up serum potassium done 2 months after discharge was normal at 4.7mmol/L.

Discussion:

Licorice contains glycyrrhizic acid which inhibits 11-beta hydroxysteroid dehydrogenase Type 2 (an enzyme that inhibits cortisol conversion to cortisone). Excess cortisol accumulates stimulating mineralocorticoid receptors and inducing a state of pseudohyperaldosteronism. Enhanced renal excretion results in clinically significant hypokalemia.

People are unaware of the significant content of licorice in preserved fruit and its side effects. The most commonly reported complications are secondary hypertension and hypokalemic myopathy. Documented fatalities were linked to its arrthymogenic effects from hypokalemia.

We report this case to increase awareness of this often-overlooked cause of hypokalemia and its significant complications.

 

Nothing to Disclose: MKSL, CJS