ABSTRACT
Biologic therapy is the mainstay of treatment of complicated inflammatory bowel diseases, which has numerous potential side effects. Among these is a rare condition known as posterior reversible encephalopathy syndrome (PRES), which is a reversible neurological disorder that results in symptoms such as headache, nausea/vomiting, blurry vision, and seizure and is diagnosed based on specific clinical and radiological features. This report presents a case of a 19-year-old woman with fistulizing Crohn's disease who was treated with infliximab, but subsequently developed PRES, which was manifested as recurrent episodes of seizures and elevated blood pressure readings, was managed supportively with antiepileptic and antihypertensive medications and eventually made a full recovery, even after resuming infliximab. This case adds to the fewer than 10 previously reported cases of PRES associated with biological therapy for inflammatory bowel disease. It highlights the need to consider this complication when prescribing these drugs.