How to distinguish seizures from non-epileptic manifestations

The first and most important step in establishing diagnosis of epilepsy consists of careful history taking from patients and witnesses. The clinical evaluation of the event will lead the indication for further diagnostic tests including e.g. EEG and MRI. Hence, identifying the paroxysmal event as epileptic or non-epileptic is the very first step in the diagnostic process. Paroxysmal events pose a clinical challenge, as these are unpredictable and do not usually occur in the doctor's office. History taking, hunting for witness reports and home-video recordings are the main tools to conclude whether a paroxysmal event is a seizure or not. In this review, we describe the most common differential diagnoses of epileptic seizures, including syncope, psychogenic non-epileptic seizures, as well as a variety of paroxysmal conditions and behaviours of all age groups. Misdiagnosis of non-epileptic events as epilepsy may not only defer the correct diagnosis and treatment but also poses additional risk by prescribing antiepileptic drugs unnecessarily. Moreover, missing the diagnosis of epilepsy implies risk of additional seizures and therefore possibly injuries, sudden death in people with epilepsy, or status epilepticus. Studies have shown that patient and witness accounts are unreliable in a high percentage of cases. Therefore, the core competency of doctors and medical professionals assessing paroxysmal events is knowledge of the clinical features that help define the different aetiologies, thus empowering them to establish the most accurate appraisal of an event. [Published with video sequences].