Posterior reversible encephalopathy syndrome following paroxysmal nocturnal hemoglobinuria: a case report and literature review.

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare acquired disorder characterized by hemolytic anemia, marrow failure, and a high incidence of life-threatening venous thrombosis. It is subject to a considerable variety of complications like intestinal obstruction and visceral embolism. The current study firstly presents a 40-year-old male with a previous diagnosis of PNH who developed posterior reversible encephalopathy syndrome (PRES) during treatment with methylprednisolone. He was referred to our department with headache and two episodes of generalized tonic-clonic seizures. Laboratory examination revealed peripheral blood cytopenias and elevated count of reticulocyte. Brain magnetic resonance imaging (MRI) exhibited abnormal signal in the bilateral parieto-occipital lobes with symmetric distribution which confirmed the diagnosis of PRES. After receive treatment of dexamethasone, anti-hypertensive and neurotropic drugs, the patient made a complete clinical recovery; and the abnormal signals of MRI were almost completely absorbed. This case shows that PRES might be a rare complication of PNH. Furthermore, it points out the necessity of rapid diagnosis and treatment of PRES.