Osmotic demyelination syndrome commonly affects the pons and infrequently involves the extrapontine region. We report a patient with severe hyponatraemia who developed osmotic demyelination syndrome as a consequence of rapid sodium correction. The condition manifested as acute severe parkinsonism, bilateral ptosis and gaze impairment. MRI revealed typical features of central pontine and extrapontine myelinolysis. The patient improved gradually after treatment with a combination of levodopa, intravenous immunoglobulin and dexamethasone. However, it is important to emphasise that the improvement of neurological symptoms is not necessarily causal with these experimental therapies.
This report deals with an elderly lady with Guillain-Barre Syndrome (GBS), who presented with features of unusually severe hyponatraemia. The hyponatraemia was probably due to the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). The hyponatraemia resolved with water restriction and infusion of hypertonic saline; GBS was treated with human immunoglobulin (IVIG). This patient's experience stresses the importance of monitoring serum sodium levels as hyponatraemia has been identified to be a marker of poor prognosis in GBS.
A 53-year-old acromegalic woman had cerebrospinal fluid rhinorrhoea following transphenoidal surgery for a pituitary microadenoma. A continuous lumbar spinal fluid drainage catheter was inserted and on the sixth postoperative day, she developed hyponatremia with features of syndrome of inappropriate antidiuretic hormone (SIADH) requiring hypertonic saline administration. Over-drainage is potentially hazardous and close biochemical monitoring is required. To our knowledge, this is the first reported case of SIADH caused by continuous lumbar drainage in an adult.