Posterior Reversible Encephalopathy Syndrome in Children: Its High Prevalence and More Extensive Imaging Findings

Background: Posterior reversible encephalopathy syndrome is a distinctive clinicoradiological entity observed in a variety of clinical settings, including pediatric patients. A greater prevalence of this syndrome has been suggested in kidney transplant recipients and patients with kidney disease. Although usually considered benign and reversible, characteristics of this syndrome in pediatric patients remain obscure. The objective of the present study involved disclosing details of imaging findings, as well as the clinical course and prevalence of the syndrome in this field. Methods: We investigated kidney transplant recipients and pediatric patients with kidney disease in our institution from 1990 to 2004. For these patients, clinical course, imaging findings, blood pressure, concurrent medical illnesses, and administrative condition of calcineurin inhibitors were analyzed. Results: Twenty cases of posterior reversible encephalopathy syndrome were investigated in patients ranging in age from 1.9 to 18.3 years. In most patients, radiological abnormalities extended to the gray matter (17 of 20 patients), frontal and temporal lobes, and even the cerebellum (16 patients). Of 177 kidney transplant recipients (cyclosporine, 127 patients; tacrolimus, 50 patients), 6 patients administered cyclosporine (4.7%) and 4 patients administered tacrolimus (8.0%) developed the syndrome after transplantation. Conclusion: Posterior reversible encephalopathy syndrome should be suspected in pediatric kidney transplant recipients and patients with kidney disease if they have a sudden episode of neurological symptoms, even if imaging findings are not restricted to the subcortical white matter of the occipital region.