A case of Guillain-Barré syndrome accompanied by syndrome of inappropriate secretion of antidiuretic hormone

• Published in: Rinsho Shinkeigaku Vol. 50; no. 10; pp. 710 - 713
• Main Authors: Inoue, Manabu, Kojima, Yasuhiro, Shirakashi, Yoshitomo, Kanda, Masutarou, Shibasaki, Hiroshi
• Format: Journal Article
• Language: English; Japanese
• Published: Japan Societas Neurologica Japonica 2010
• Subjects: Aged; Guillain-Barre Syndrome - complications; Guillain-Barré syndrome; Humans; Hyponatremia; Inappropriate ADH Syndrome - complications; Male; SIADH
• ISSN: 0009-918X; 1882-0654
• DOI: 10.5692/clinicalneurol.50.710

A 73-year-old Japanese male was admitted because of difficulty in standing up after acute upper respiratory inflammation with mild fever followed by watery diarrhea. Neurological examination revealed moderate proximal muscle weakness and loss of tendon reflexes in all extremities. The blood sodium level was 106mEq/l on admission. The blood level of antidiuretic hormone (ADH), renin and aldsterone was 11.3pg/ml (normal value 0.3-4.2), 0.2ng/ml/h (0.2-2.7) and less than 10.0pg/ml (38.9-307.0), respectively. The plasma osmolarity was 221mOsm/kg (270-295) , and the urine osmolarity was 416mOsm/kg (50-1,400). EMG and nerve conduction studies suggested acute demyelination in the motor and sensory nerves. CSF revealed 10cells/mm3 and elevated protein to 98mg/dl. The clinical course, laboratory data and electrophysiological findings suggested coexistence of the syndrome of inappropriate secretion of ADH (SIADH) and Guillain-Barré syndrome (GBS) from the very early clinical stage of the diseases. The clinical and laboratory findings improved after intravenous administration of saline over three weeks. When GBS is associated with SIADH, hyponatremia is commonly seen at the peak of motor paralysis, often accompanied by autonomic or respiratory failure requiring mechanical ventilation. This was not the case in the present patient. It is postulated that SIADH, like GBS, might be caused by an autoimmune mechanism.