Posterior reversible encephalopathy syndrome on ¹⁸F-FDG PET/CT in a pediatric patient with Burkitt's Lymphoma

We present a case of posterior reversible encephalopathy syndrome (PRES) in a pediatric patient with Burkitt's lymphoma predominantly involving the bone marrow. ¹⁸F-FDG PET/CT scan obtained after the first cycle of chemotherapy, complicated by acute kidney injury, hypertension, tumor lysis syndrome, and lethargy with focal neurological symptoms, showed a favorable marrow and lymph node response but increased FDG uptake in the bilateral frontal and occipital cortical/subcortical regions. Brain MRI was consistent with PRES. The patient was managed with IV hydration and blood pressure control with symptom resolution. This case shows the ¹⁸F-FDG uptake pattern of PRES in postchemotherapy setting.