Abstracts

Rationale: The diagnosis of epilepsy can be difficult, and misdiagnosis is common in all age groups. This has major health and social consequenses. Convulsive syncope is the most common condition misdiagnosed as epilepsy. Head-Up Tilt (HUT) testing is the gold standard diagnostic test for neurally mediated syncope (NMS) and might be helpful if used earlier in the investigation of convulsions and other paroxysmal events in children. Methods: A systematic retrospective chart review of all children under 18 years of age undergoing HUT at one institution 2001-2007. We used pre-determined diagnostic criteria and systematically characterised HUT responses. HUT results were correlated with clinical data from the chart review. Simple descriptive statistics were used. Results: Data on 66/97 children tested is available at the time of submission: 73% female; ages 8-17 years (median 14). Symptoms had been present for over 2 years in 50% (range 0-9; median 1). Symptoms included convulsions in 46%, non-convulsive transient loss of consciousness (TLOC) in 27%. 50% had had a previous EEG. On HUT 44% had reproduction of symptoms including those with significant alterations in blood pressure and or heart rate (27%) and 17% with medically unexplained symptoms. Conclusions: Many children had waited a long time for HUT; which was often undertaken after a standard EEG. The yield of useful results in this population was high, leading to a diagnosis of NMS or postural tachycardia syndrome in 27% and a diagnosis of medically unexplained TLOC in 17%. HUT should be considered earlier in the investigation of convulsions and other paroxysmal events in children.