“…Occa sionally, autonom ic nerves are involved, in which case there may be urinary retention, postural hypotension, or hypertension. Hypertension may be found in the course of GBS in 33% o f patients [3], The pathophysiologic basis for hypertension in GBS is unclear and reports have variously implicated sympathetic overactivity [4,5], increased renin release [6], and baroreceptor dys function [7], Our patient showed transient hypertension in accord with an overactivity of the sympathetic ner vous system assessed by increased plasma and urinary catecholamines. On the other hand, it is well known that GBS may cause SIADH, though the pathophysiologic basis is also unclear.…”