[P1-37] Mesial Temporal Lobe Epilepsy with Hippocampal Sclerosis Following Reversible Posterior Reversible Encephalopathy Syndrome
[Introduction] Posterior reversible encephalopathy syndrome (PRES) is rarely followed by hippocampal sclerosis (HS) and mesial temporal lobe epilepsy (mTLE).
[Case] A boy underwent stem cell transplantation at 7y4m for treatment of relapsed malignant lymphoma, and tacrolimus was used for immunosuppression. On 36 days after transplantation his consciousness suddenly deteriorated, associated with elevated blood pressure, headache, and rightward eye deviation. EEG showed repetitive spikes in left central region, suggesting nonconvulsive status epilepticus. Brain MRI showed elongated T2 signal and enhanced diffusion in bilateral occipital white matter indicating PRES. Left hippocampus showed restricted diffusion and decreased ADC value. He completely recovered after cessation of tacrolimus and intravenous administration of midazolam.
From 10y6m (3 years after transplantation), he had repeated episodes of nausea, motionlessness, and disturbed consciousness. EEG showed spikes in left anterotemporal region.Left hippocampus was atrophic on MRI with high signal on FLAIR. These findings led to the diagnosis of mTLE with HS. He finally had daily seizures resistant to levetiracetam, and underwent surgical treatment (left anterior temporal lobe resection and multiple hippocampal transection) at 11y9m. His seizure has been completely suppressed for 6 months after the surgery.
[Discussion] PRES usually presents with acute seizures though infrequently results in remote epilepsy. mTLE with HS commonly follows prolonged febrile seizures in infancy. In cases of mTLE, the onset of PRES is rare and less than 10 years of age in most cases. Normal brain MRI before stem cell transplantation strongly suggests that PRES caused HS in this case.
[Case] A boy underwent stem cell transplantation at 7y4m for treatment of relapsed malignant lymphoma, and tacrolimus was used for immunosuppression. On 36 days after transplantation his consciousness suddenly deteriorated, associated with elevated blood pressure, headache, and rightward eye deviation. EEG showed repetitive spikes in left central region, suggesting nonconvulsive status epilepticus. Brain MRI showed elongated T2 signal and enhanced diffusion in bilateral occipital white matter indicating PRES. Left hippocampus showed restricted diffusion and decreased ADC value. He completely recovered after cessation of tacrolimus and intravenous administration of midazolam.
From 10y6m (3 years after transplantation), he had repeated episodes of nausea, motionlessness, and disturbed consciousness. EEG showed spikes in left anterotemporal region.Left hippocampus was atrophic on MRI with high signal on FLAIR. These findings led to the diagnosis of mTLE with HS. He finally had daily seizures resistant to levetiracetam, and underwent surgical treatment (left anterior temporal lobe resection and multiple hippocampal transection) at 11y9m. His seizure has been completely suppressed for 6 months after the surgery.
[Discussion] PRES usually presents with acute seizures though infrequently results in remote epilepsy. mTLE with HS commonly follows prolonged febrile seizures in infancy. In cases of mTLE, the onset of PRES is rare and less than 10 years of age in most cases. Normal brain MRI before stem cell transplantation strongly suggests that PRES caused HS in this case.