Malignant Hypercalcemia: A Rare Etiology of Posterior Reversible Encephalopathy Syndrome.

Posterior reversible encephalopathy syndrome (PRES) is a rare and severe neurotoxic encephalopathic state characterized by variable neurologic manifestations ranging from headache and confusion to seizures, coma, and reversible subcortical vasogenic edema on imaging. PRES is commonly induced by chronic renal failure, hypertension, chemotherapeutic drugs, and eclampsia. PRES induced by hypercalcemia is uncommon and not widely underlined in the literature. We underline a case of a 61-year-old female diagnosed with advanced breast carcinoma presented with altered sensorium and generalized limb weakness. She was found to have malignant hypercalcemia, and brain imaging demonstrated subcortical vasogenic edema in the occipital and frontal lobe, suggestive of PRES. Her condition gradually improved after the treatment of hypercalcemia.