Posterior reversible encephalopathy syndrome (PRES) is a neurological disorder characterized by varied neurological symptoms. There are two leading theories regarding the pathophysiology: hypertension crisis and endothelial dysfunction.
We report the case of a 42-year-old patient with history of hypertension. She presented to the emergency department with headache and bilateral loss of vision. She described one previous episode of witnessed generalised tonic-clonic seizure at home. She was found to have an elevated blood pressure (BP) of 210/105 mm Hg. An ocular examination revealed a diminished vision and perception of hand movement on both eyes. Laboratory findings were within normal range except for potassium, which was 2.7 mEq/l (normal range 3.55). Brain MRI showed bilateral posterior parietooccipital hyper densities in the cortex and subcortical white matter consistent with PRES. Antihypertensive therapy was started. The patients headache rapidly resolved and her vision improved. The patient was discharged symptom-free on potassium supplements and antihypertensive therapy. After discharge the patient was referred to the Endocrinology service. Aldosterone concentration/plasma renin activity ratio was positive and the saline infusion test confirmed the diagnosis of hyperaldosteronism. Abdominal MRI revealed a two-centimetre adenoma of the left adrenal gland. The patient underwent surgery to remove the adenoma. After surgery, hypokalemia and hypertension resolved.
Although primary aldosteronism (PA) is not included among the reported causes of PRES, it is important to consider its existence in PRES patients, particularly in those with hypokalemia. The occurrence of PRES in patients with PA might be independent of hypertension since the direct action of aldosterone on the mineralocorticoid receptor may cause endothelial dysfunction.
20 - 23 May 2017
European Society of Endocrinology