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The advances made in genetic knowledge of epilepsy have led to the description of new epilepsy syndromes and to a better characterization of known ones. However, the genes responsible for the most common forms of idiopathic epilepsy remain mostly unknown. This means that for the time being, in clinical practice, genetic diagnosis is limited to uncommon syndromes and to cases in which treatment decisions or genetic counseling can be derived from the diagnosis.

It is currently known that membrane transporter proteins are increased in brain tissue of refractory epileptic patients and in animal models of epilepsy and that overexpression of these transporters and their inhibition are correlated with a reduction and an increase, respectively, of epileptic drugs in epileptic tissue (pharmacokinetic hypothesis). It has also been shown that alterations in voltage-gated sodium channels and GABAA receptors are responsible for resistance to some epileptic drugs. These changes may be constitutional (genetically determined) or acquired (as a consequence of the seizures themselves or disease progression) and may seem alone or combined with each other (pharmacodynamic hypothesis). Associations have been shown between certain genetic polymorphisms and resistance to epileptic drugs, and although they have not been replicated by all authors, they constitute a very attractive line of research. More detailed knowledge of these molecular mechanisms will probably lead to the development of new strategies for pharmacological treatment of epilepsy.

Episodes of loss of consciousness are common, even in young, healthy people, and can sometimes represent a diagnostic challenge. The main diagnoses to consider are syncope and epileptic seizures, both of which may have similar symptomatology such as dizziness, loss of consciousness, falls, or “convulsive” phenomena. We present the case of a young male patient with a background of two venous thrombosis episodes (superior vena cava thrombosis and cerebral venous thrombosis), attributed to protein C and S deficiency and complicated by high intracranial pressure. A lumboperitoneal shunt was performed and anticoagulant therapy was initiated. He did not experience any medical problems until several years later, when he suddenly began to develop frequent, repetitive, transient episodes of dizziness, followed by loss of consciousness. Simultaneous video‐EEG and ECG performed during these events showed a typical pattern normally observed during syncope. Due to the absence of changes in heart rate or blood pressure, and taking into account his medical history, intracranial hypertension was considered as a possible cause of cerebral hypoperfusion. Cerebral arteriography demonstrated chronic thrombosis of all the cerebral sinuses, and the lumbar puncture an intracranial pressure of 47 mm Hg. The lumboperitoneal shunt was replaced and the patient has since not presented with any episodes. The use of simultaneous video‐EEG and ECG is a reliable and efficient approach to differentiate between syncope and seizure and in this case, was the key to finding the cause of these episodes. [Published with video sequences]

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