Potentially life-threatening cardiac dysrhythmia in a child with selenium deficiency and phenylketonuria.

Selenium deficiency is a frequent finding in children with phenylketonuria (PKU) receiving dietary treatment. We report the occurrence of episodic ventricular tachycardia in a 9-month-old infant with PKU. Serum selenium (Se), 0.13 mumol/l (normal range 0.28-1.12 mumol/l, mean +/- 2 SD), and whole blood glutathione peroxidase (GSHPX), 16 U/g Hb (normal range 19.5-34.3 U/g Hb, mean +/- 2 SD), were low. Auscultation of cardiac rhythm is recommended during the routine follow-up of young children with PKU. Se deficiency should be considered in the aetiology of a dysrhythmia and corrected with Se supplementation.