Atypical Manifestations of Posterior Reversible Encephalopathy Syndrome (PRES) Complicating Cytotoxic Chemotherapy during the Treatment of Acute Lymphoblastic Leukemia in a Child

Posterior reversible encephalopathy syndrome (PRES) is a rare cause of acute encephalopathy but can be observed in children under chemotherapy. We herein report a case of PRES in a 13-year-old boy with an acute lymphoblastic leukemia following treatment with intrathecal and intravenous chemotherapy. On Magnetic Resonance Imaging (MRI) the thalamic nuclei and cortex involvement accompanied the classical subcortical localization in parietal and occipital lobes. In addition, cytotoxic edema, instead of the vasogenic edema classically occurring in PRES, was observed. Cortical atrophy was seen after regression of other MRI findings. This case shows that PRES with an atypical appearance on MRI should be considered in children in case of acute encephalopathy occurring during chemotherapy treatment.