Reversible Coma in a Young Postpartum Woman
A 22-year-old woman presented at 36 weeks of gestation with a 1-day history of mild headache, blurred vision, and epigastric pain. She was admitted for severe preeclampia with signs of early labor. Treatment with magnesium sulfate and IV labetolol was started. During labor, however, she experienced multiple generalized tonic clonic seizures. Despite a normal vaginal delivery, she remained postictal.
Neurologic exam was notable for withdrawal of all 4 extremities to painful stimuli. Pupils were mid-position fixed and deep tendon reflexes were 2+ with extensor plantar response bilaterally. She had decorticate posturing. IV levetiracetam was started, and she was transferred to the ICU. Brain CT without contrast showed marked diffuse vasogenic cerebral edema (Figure). It also showed partial bilateral uncal herniation and effacement of the suprasellar cistern. Bilateral low attenuation of frontal and occipital lobes was noted. This was most likely the result of marked edema presumed to be related to posterior reversible encephalopathy syndrome (PRES).
The development of focal neurologic deficits postpartum is uncommon. Differential diagnoses include seizures, posterior circulation stroke, cerebral venous thrombosis, complicated migraine, eclampsia, encephalitis, vasculitis, cerebral artery dissection, and PRES.
Key Points: The reported incidence of PRES is approximately 0.01%. PRES is a cliniconeuroradiologic entity. Clinical features include headache, confusion, seizures, cortical visual disturbances, and altered metal status. Radiologic findings include bilateral white and gray matter changes that predominantly affect the posterior cerebral hemispheres. Common causes include hypertension, preeclampsia/eclampsia, uremia, immunosuppressive drugs, transplantation, and SLE.
Eclamptic patients with atypical features such as focal neurologic deficits, markedly depressed mental status, and profound visual disturbances should be evaluated by neuroimaging. CT in this setting may help differentiate PRES from stroke. PRES is a reversible syndrome with excellent recovery in most patients within a few weeks. Early and accurate diagnosis helps ensure optimal outcomes.
Case and photo courtesy of Ranjita Pallavi, MD and Hossam Amin, MD.