AAN recommendations for diagnostic assessment of the child with status epilepticus

A recently-published American Academy of Neurology (AAN) Practice Parameter provides evidence-based recommendations for the diagnostic assessment of the child with status epilepticus.The Practice Parameter was developed by the Quality Standards Subcommittee of the AAN and the Practice Committee of the Child Neurology Society upon review of evidence on diagnostic testing in children with status epilepticus. The reviewed diagnostic tests included blood cultures, lumbar puncture, antiepileptic drug (AED) levels, toxicology studies, EEG, and neuroimaging studies.Data from 20 studies in 2,093 children showed that status epilepticus was attributed to an acute symptomatic cause in 26%, a remote symptomatic cause in 33%, a remote symptomatic with an acute precipitant in 1%, a progressive encephalopathy in 3%, febrile status epilepticus in 22%, and cryptogenic in 15%.There were insufficient data to make recommendations regarding whether blood cultures or lumbar puncture should be routinely performed in children in whom there is no clinical suspicion of infection. However, the Practice Parameter recommends that AED levels should be considered in children with epilepsy who are on AED prophylaxis and develop status epilepticus, as the data showed that around a third of such children had low AED levels (although this was not necessarily the cause of the event).A diagnosis of ingestion was documented in 3.6% of 1,221 children enrolled in 11 studies, and the authors say, "We deemed this yield high enough to consider testing with specific serum toxicology levels, if indicated, since establishing the diagnosis is critical to treatment." Accordingly, toxicology testing is recommended in children with no immediately-apparent SE etiology.Similarly, approximately 4% of children in nine studies were diagnosed with an inborn error of metabolism, and metabolic studies for such conditions may be considered when the etiology remains unknown after initial evaluation, particularly if there is a history suggestive of a metabolic disorder. The authors suggest EEGs may help determine whether there are focal or generalized epileptiform abnormalities. EEGs may also be helpful when there is a suspicion of pseudostatus epilepticus (nonepileptic SE), or nonconvulsive SE. The authors considered the evidence insufficient to provide recommendations on routine neuroimaging, but they say, "Neuroimaging can identify structural causes for SE, especially to exclude the need for neurosurgical intervention in children with new onset SE without a prior history of epilepsy, or in those with persistent SE despite appropriate treatment." If neuroimaging is performed, they note that it should only be done after the child is stabilised and seizure activity is controlled. Reference...