Dear Editor, Posterior reversible encephalopathy syndrome (PRES), first reported by Hinchey et al. [1] in 1996, is an emerging neurological illness. It is characterized by headache, altered consciousness, visual disturbance, and seizures, with typical radiographic findings of vasogenic edema involving the posterior cerebral region. With widespread utilization of magnetic resonance imaging (MRI), PRES is becoming more familiar to adult physicians. However, because of the relatively sparse number and relatively recent appearance of reports on PRES in the pediatric literature compared to the adult literature, this condition is less well addressed in field of pediatric critical care. Between 2005 and 2011, seven children (age 7–17 years) admitted to our pediatric intensive care unit (PICU) with a confirmed diagnosis of PRES were retrospectively investigated. Their initial and follow-up data, including underlying diseases, precipitating factors, clinical manifestations, neuroimaging characteristics, and outcomes, were analyzed (Table 1). The underlying diseases included collagen diseases, glomerulonephritis, renovascular hypertension, and malignancies. Precipitating factors were hypertension, immuno-suppressants, anti-neoplastic agents, and hemodialysis. Initial neurologic manifestations included seizures (100 %), mental change (100 %), headache (86 %), and visual disturbance (71 %). Hypertensive crisis occurred in five patients. The initial MRI scans of all patients showed typical vasogenic edema distributed in the subcortical white matter of the parieto-temporo-occipital regions. Moreover, six patients also had atypical MRI lesions, such as atypical distribution, cytotoxic edema, and abnormal contrast enhancement [2]. After meticulous treatment with antihypertensive agents, anti-epileptics, and the withholding of potential offending medications, all patients achieved complete clinical recovery with subsequent radiological resolution. To our knowledge, this is the first case series to describe PRES in the setting of PICU. Intriguingly, we found that even though the underlying conditions and predisposing factors varied per patient, all our patients had initial manifestations of mental status change, seizures, and hypertension. Early diagnosis has an important therapeutic implication for PRES because its prognosis is often benign when managed timely, with complete clinical reversal within days or weeks [1]. In contrast, delayed diagnosis and improper management may result in permanent brain damage or even death [3]. While neurologic manifestations can be nonspecific in PRES, hypertension, which is present in 70–80 % of PRES patients, is usually a diagnostic hallmark [1, 2]. However, unlike in adults, hypertension in children is frequently unrecognized by their health care providers [4], especially in the setting of the neurologic emergency unit, while high blood pressure caused by agitation or hyper-sympathetic tone induced by seizures may confound the diagnosis of hypertension. Consequently, it is not uncommon that children with PRES are found to be hypertensive only late in the clinical course, but not at the disease onset [5]. Our observation highlights the importance of intensive monitoring of blood pressure in children with critical neurologic illness and that pediatricians should keep PRES in high suspicion when hypertension is found in the context of acute encephalopathy. In conclusion, PRES can complicate a variety of underlying conditions among critically ill children. In children presenting initially with seizures and hypertension, physicians should consider PRES within a comprehensive differential diagnosis of acute encephalopathy, since early recognition and intensive care are essential to a completely reversible outcome in children with PRES.