Posterior Reversible Encephalopathy Syndrome and Azathioprine.

Posterior reversible encephalopathy syndrome (PRES) is a rare syndrome that presents with neurological manifestations, often associated with arterial hypertension. Magnetic resonance imaging (MRI) shows bilateral white matter oedema in the posterior vascular territories. Immunosuppression, (pre) eclampsia and autoimmune diseases can be implicated. A 27-year-old woman, with mixed connective tissue disease under azathioprine, was admitted in the emergency room in status epilepticus and with severe hypertension. The MRI showed bilateral oedema in a pattern compatible with PRES. There was clinical improvement after azathioprine suspension. PRES is typically reversible with prompt recognition of the syndrome and its trigger. The association with azathioprine is rare. LEARNING POINTS: Posterior reversible encephalopathy syndrome should be considered in patients with sudden onset of headache, altered consciousness and seizures.Recognition of this entity and identification of the trigger are essential for reversal of the clinical picture.Autoimmune diseases and some immunosuppressive drugs have been identified as causative, but reports of an association with azathioprine are very rare.