[Propionic acidemia and long QT syndrome: A potentially serious combination].

Propionic acidaemia (OMIM 606054) is an autosomal recessive organic acid metabolism disorder that involves a defective form of propionyl-CoA carboxylase (PCC). The disease usually manifests with acute and potentially fatal episodes of metabolic decompensation and delays in cognitive development. Its association with cardiomyopathy, usually dilated, is well known, and usually manifests during the episodes of metabolic decompensation. More recently, propionic acidaemia has been associated with long QT syndrome1,2 (the normal range in children older than 1 year is defined by a heart-rate corrected QT interval [QTc] < 440 ms),3 which can predispose the patient to the development of ventricular arrhythmias and sudden death. Its exact aetiology is not known and its treatment is similar to that of long QT without associated propionic acidaemia. We present the case of one girl with propionic acidaemia in whom the electrocardiogram (ECG) revealed prolongation of the QTc.