Polyuria during Guillain-Barré syndrome.

Severe Guillain-Barré syndrome (GBS) usually results in life-threatening autonomic disturbances requiring a close monitoring of the patient in an Intensive Care Unit. Besides dangerous cardiac manifestations, neuroendocrine changes are also reported and could induce electrolytes and fluid balance impairments. Polyuria has been observed in a severe case of GBS occurring in a 16-year-old boy. Consecutive blood samples were obtained for renin, aldosterone, antidiuretic hormone and atrial natriuretic factor measurements. Polyuria in GBS is multifactorial and would be partly due to a dysregulation of osmoreceptors.