Extensive reversible brain magnetic resonance lesions in a patient with HELLP syndrome.

A severe form of toxemia of pregnancy with microangiopathic hemolytic anemia, elevated liver enzymes, and low platelets has been called the HELLP syndrome. A patient with the HELLP syndrome developed a severe, reversible encephalopathy. Brain computed tomography and magnetic resonance imaging showed abnormalities consistent with edema limited to the posterior circulation territory. The location of the lesions and their occurrence in the HELLP syndrome support suggestions that the vulnerability of posterior structures in eclamptic encephalopathy is due to a vascular susceptibility of the posterior circulation and that endothelial cell dysfunction plays an important role in the pathogenesis of eclamptic encephalopathy.