Usefulness of the head-upright tilt test for distinguishing syncope and epilepsy in children

Purpose: Episodic loss of consciousness in children, whether or not associa ted with hypertonia or short-duration clonic movements, presents a diagnost ic challenge to the pediatrician and child neurologist. We provide some evi dence of the usefulness of the head-upright tilt test for investigating the causes of transient loss of consciousness in children, and for distinguish ing between syncope, convulsive syncope, and epilepsy. Methods: We studied nine children previously diagnosed as epileptic on the basis of compatible clinical events and epileptiform findings in routine EE Gs who were treated over the Long term with antiepileptic drugs, but whose clinical records suggested syncope or convulsive syncope rather than epilep sy on reevaluation. All subjects underwent head-upright tilt testing. Results: The tilt-test result was positive in all nine cases, with the pati ents reporting the same symptoms as in the previously considered epileptic attacks. Conclusions: Inadequate histories and misuse/over- interpretation of EEG re sults often lead to misdiagnosis of epilepsy in children. The head-upright tilt test is a useful and reliable diagnostic technique, allowing syncopal events to be induced and evaluated under controlled conditions. In a subset of patients. it may help to distinguish epilepsy from simple or convulsive syncope.