Clinical and neuroimaging findings in children with posterior reversible encephalopathy syndrome

Objective To clarify the clinical and radiological spectrum of posterior reversible encephalopathy syndrome (PRES) in children, and to identify the prognostic factors. Methods The records of 40 children with PRES were reviewed. Acute clinical symptoms, MRI including apparent diffusion coefficient (ADC) maps in the acute and follow-up periods and neurological sequelae, including epilepsy, were noted. Results Age at onset ranged from 2 to 16 years. Underlying disorders were hematological or neoplastic disorders (n = 20), renal diseases (n = 14) and others (n = 6). In the acute period, 31 patients had seizures, 25 had altered consciousness, 11 had visual disturbances and 10 had headache. Of 29 patients who had ADC maps in the acute period, 13 had reduced diffusivity as shown by ADC within PRES lesions. Of 26 patients with follow-up MRI, 13 had focal gliosis or cortical atrophy. No patients had motor impairment, and four patients had focal epilepsy. No clinical variables were associated with focal gliosis or cortical atrophy on follow-up MRI, but lesional ADC reduction in the acute period was prognostic for focal gliosis or cortical atrophy on follow-up MRI (p = 0.005). Conclusions To the best of our knowledge, this is the largest cohort study to date involving PRES in children. Acute symptoms in pediatric patients are similar to those reported in adults, but altered consciousness was more frequent in children. Lesional ADC reduction in the acute period was common and was a good predictor of later, irreversible MRI lesions.