Abstract

  Liddle’s syndrome is a rare genetic autosomal dominant disease affecting the activity of the epithelial sodium channels (ENaC) or the amiloride-sensitive sodium channels, which leads the kidneys to excrete potassium but retain too much sodium and water causing early, frequent and severe, high blood pressure associated with low plasma renin, metabolic alkalosis and normal to low levels of aldosterone [1,2]. Disease-associated mutations either activate the channel directly or abrogate aldosterone-inhibited retrieval of ENaC subunits from the plasma membrane [3]. The end result of these mutations is increased expression of activated ENaC channels at the plasma membrane of principal cells which manifests as severe early onset hypertension with hypokalemia unresponsive to spironolactone [4]. We observed an isolated case of a Liddle’s syndrome in a 23-year-old man who presented with signs of acromegaly. The patient initially presented to the emergency room with palpitations, weakness of the extremities and a three-year history of low potassium levels and uncontrolled hypertension. Six months later he was admitted again to the hospital with signs of hypokalemia, including palpitations, fatigue and weakness. Upon further evaluation, he was found to have low renin and aldosterone levels. Physical examination revealed mild diastolic hypertension, acromegalic features, weight gain, excessive sweating, widening of both hands and feet [5]. Laboratory results revealed increased levels of GH and IGF-1-a. After oral administration of oral glucose levels of IGF-1 remained elevated. MR imaging of the brain revealed a 1.3 x 1.2 x 0.7 cm pituitary adenoma. A diagnosis of acromegaly and Liddle syndrome was made. Coexisting acromegaly and Liddle syndrome are reported together only in rare cases and it can be explained due to enhanced renal and extrarenal ENaC activity.

Keywords: Liddle’s Syndrome; Epithelial Sodium Channels (ENaC); Acromegaly

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Citation

Citation: Juna Musa., et al. “Liddle’s Syndrome Associated with Acromegaly due to Enhanced Renal and Extrarenal ENaC Channel Activity: The First Case Report that Explained this Rare Association". Acta Scientific Medical Sciences 4.5 (2020): 79-83.

Copyright

Copyright: © 2020 Juna Musa., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.