Abstracts

Rationale: Seizure following solid organ transplantation is a common reason for pediatric neurology consultation at pediatric organ transplant centers. The reason for seizure and the risk of seizure recurrence are key questions in this context. The purpose of this study is to determine the causes of seizures and risk factors for seizure recurrence in pediatric patients following solid organ transplantation.Methods: The study was a retrospective chart review in which we analyzed the charts of all patients under the age of 19 years who had undergone solid organ transplantation and subsequently had a seizure. Subjects were identified using the Stanford Translational Research Integrated Database Environment (STRIDE), which is an anonymized database of patient information derived from the institution's electronic medical records system between 1995 and 2013. Information regarding demographics, transplant history, seizure cause, and future epilepsy was obtained by chart review.Results: We identified 80 pediatric patients who had solid organ transplantation with subsequent seizure. Organs transplanted included heart (n=27), liver (n=20), kidney (n=20), heart/lung (n=5), liver/intestine (n=3), intestine (n=2), liver/kidney (n=2), and intestine/stomach/pancreas (n=2). The most common reason for seizure after transplant was posterior reversible encephalopathy syndrome (PRES; n=23). Other causes included cerebrovascular injury (n=15), medication toxicity (n=13), infection (n=7), underlying condition (n=7), unknown cause (n=7), metabolic derangement (n=5), and neoplasm (n=3). Seizure causes differed based on which organ was transplanted and the time elapsed since transplantation. Following heart, kidney and intestine transplantation, PRES was the most common cause of seizure, whereas medication toxicity was the most common cause of seizure following liver transplantation. Of those with seizures following transplant, 60% (n=48) of subjects had acute symptomatic seizures, whereas 40% (n=32) had a diagnosis of epilepsy. The main risk factors for epilepsy post-transplant were structural brain lesions (n=20) and pre-transplant epilepsy (n=11).Conclusions: The cause of seizure following solid organ transplantation varies by the organ transplanted and the time interval since transplantation. Overall, PRES was found to be the most common cause of seizure following transplantation. Though seizures are commonly self-limited in this context, structural brain injury and pre-transplant seizures are associated with post-transplant epilepsy.