Posterior Reversible Encephalopathy Syndrome in a Patient With Macrophage Activation Syndrome and Herpes Simplex Virus 2

Posterior reversible encephalopathy syndrome (PRES) is a symptomatic and radiographic syndrome characterized by neurologic changes and concomitant neuroimaging findings typically involving posterior cerebral white matter edema. While there are many competing views on the pathophysiology of PRES, inflammatory conditions, particularly autoimmune diseases, tend to have some degree of correlation. Most cases where patients who have PRES and autoimmune diseases typically involve systemic lupus erythematosus. There is relatively little information in the literature on PRES occurring in adult patients with hemophagocytic lymphohistiocytosis (HLH)/macrophage activation syndrome or of concomitant herpes simplex virus 2 (HSV2) infection. Here, we present the case of a patient with PRES in the setting of adult-onset Still’s disease and HLH with concomitant HSV2 infection.