Liddle syndrome: A case report

Liddle syndrome is an autosomal dominant hereditary disease caused by a single gene mutation. Typical clinical manifestations are early-onset hypertension and hypokalaemia and can be treated using ENaC blockers (amiloride and aminopterin).

This report describes a 17-year-old male with hypertension and hypokalaemia. We performed a Captopril inhibition test and a postural stimulation test for the diagnosis and typing of primary aldosteronism.

The serum renin was low, and aldosterone was high, so the patient was initially misdiagnosed as primary aldosteronism. After a genetic analysis, a diagnosis of Liddle syndrome was made due to the presence of an SCNN1B p.Pro617Ser mutation. After diagnosis, the patient was administered one tablet of amiloride twice a day (each tablet contains 2.5mg of amiloride hydrochloride and 25mg of hydrochlorothiazide 25mg). The patient's blood pressure (average of 120-135/70-80mmHg) and serum potassium levels (3.6-4.0mmol/L) returned to normal and were well-controlled after treatment.

The patient is an atypical case of Liddle syndrome; genetic analysis is helpful and essential for diagnosis.