A Clinical Phenotype Mimicking Essential Hypertension in a Newly Discovered Family With Liddle's Syndrome

作者：Rossi Ermanno^*; Farnetti Enrico; Nicoli Davide; Sazzini Marco; Perazzoli Franco; Regolisti Giuseppe; Grasselli Chiara; Santi Rosaria; Negro Aurelio; Mazzeo Vincenzo; Mantero Franco; Luiselli Donata; Casali Bruno

来源：American Journal of Hypertension, 2011, 24(8): 930-935.

DOI：10.1038/ajh.2011.76

• aldosterone
• amiloride
• blood pressure
• epithelial sodium channel
• hypertension
• Liddle's syndrome
• plasma potassium
• renin

BACKGROUND
Liddle's syndrome (LS) is a monogenic form of hypertension simulating a mineralocorticoid excess, and is currently suspected in young hypokalemic hypertensives. The aims of the study were: (i) to evaluate the clinical phenotype of LS in a newly identified Italian family of Sicilian origin carrying a gain-of-function mutation of the beta subunit of the epithelial sodium channel (ENaC) (P617L) previously reported by our group in an apparently unrelated Sicilian patient presenting the typical phenotype of LS including hypokalemia; (ii) to determine whether an unknown biological relationship exists between the newly identified family and the family of the proband previously reported.
METHODS
Genetic analysis was performed in the present family, in the individual in which the beta P617L mutation was first observed, and in his relatives.
RESULTS
beta P617L mutation was identified in the proband and in three maternal relatives. None of them showed hypokalemia. Mild to severe early onset hypertension and left ventricular hypertrophy were present in all of them. Analysis of mitochondrial DNA (mtDNA) and gamma chromosome profiles in the present family and in the proband's family previously reported showed the absence of a relationship between them. The availability of only one carrier of the mutation in one of the two families meant that a genetic analysis able to assess a founder effect was not feasible.
CONCLUSIONS
LS should be considered in all cases of early onset hypertension, independently of the plasma potassium concentration. The incidence of LS may be greater than is currently thought, because hypokalemia is not invariably present.

• 出版日期2011-8