Electrolyte screening in the evaluation of prolonged QTc interval.

We present a case of a previously healthy adolescent male for outpatient evaluation of prolonged QT interval. He was ultimately found to have acquired QT interval prolongation secondary to hypocalcaemia related to undiagnosed hypoparathyroidism. This case report highlights the importance of routine electrolyte analysis, even in the outpatient setting, during initial diagnostic workup for QT interval prolongation.