Atypical Posterior Reversible Encephalopathy Syndrome in Puerperium

A 37-year-old woman with no significant past medical history presented on the 4th day of puerperium with sudden headache and severe bilateral visual disturbance (blurring and teichopsia) followed by isolated generalized tonic-clonic seizure. No other impairment was observed at neurological examination. Arterial blood pressure was consistently elevated (180/110 mm Hg). Blood and urine routine assays were normal, and no proteinuria was detected during both the pregnancy and puerperium. Cranial CT scan was unremarkable, whereas MRI FLAIR and FSET 2 sequences revealed scattered areas of increased signal in subcortical occipital and posterior parietal white matter, and more confluent areas of signal hyperintensity in the grey matter of the striatum, in the external and internal capsule bilaterally and in the upper brainstem ( fig. 1 a, b). Diffusion-weighted images (DWI) revealed signal isointensity or slight hyperintensity of the affected areas with an increase in the apparent diffusion coefficient (ADC) indicating vasogenic edema. MR venography was also performed to evaluate the deep venous system, and resulted normal. The patient was treated with labetalol 20 mg i.v. for 2 min followed by 40 mg i.v. at 10-min intervals until normalization of Dear Sir, Posterior reversible encephalopathy syndrome (PRES) is a clinical and radiological entity characterized by headache, visual loss and epileptic seizures in a severe arterial hypertension setting due to hypertension-inducing diseases, such as renal diseases or eclampsia [1, 2] . Moreover, PRES can also be caused by hypertension-inducing treatments (i.e. erythropoietin, blood transfusion or immunosuppressants) [1] . Brain MRI typically documents vasogenic edema involving the occipitoparietal regions [3] as a result of loss of cerebral autoregulation related to hypertensive endothelial dysfunction and disruption of blood-brain barrier with increased permeability [4] . If PRES is diagnosed at the right time, both clinical signs and neuroradiological pattern are frequently reversible, whereas delayed diagnosis and treatment can lead to ischemic or hemorrhagic lesions with permanent neurological damage [4] . Edema can rarely involve the brainstem or the hemispheric deep structures. In this case, the resulting syndrome is called atypical PRES [5] . Misdiagnosis is a frequent event and involves vertebrobasilar ischemia, cerebral venous thrombosis and metabolic diseases. Here, we report two unusual cases of atypical PRES during puerperium with good outcome. Received: January 31, 2007 Accepted: May 22, 2007 Published online: January 29, 2008