Background: A previously healthy 23-year-old man presented with a short history of abdominal pain and diarrhoea followed by blurred vision, severe postural hypotension, reduced sweating and unremitting fever.
Methods: Examination revealed fixed dilated pupils, impaired sweating and postural hypotension. Clinical and neurophysiological examination showed no motor or sensory deficit. A diagnosis of idiopathic autonomic neuropathy was made. He became gravely ill with profound life-threatening hypotension and a prolonged ileus.
Findings: Within 36 h of receiving intravenous gammaglobulin (IVGG) his pupillary areflexia and severe hypotension resolved. 2 weeks later the autonomic failure recurred but again responded to treatment with IVGG. IVGG is a recognised treatment for Guillain-Barré syndrome.
Interpretation: This case report demonstrates that IVGG is also effective in the rare pure dysautonomic variant.