Localization of lesion in patients with idiopathic orthostatic hypotension.

Localization of lesion in patients with idiopathic orthostatic hypotensionSir:Idiopathic orthostatic hypotension is a fascinating condition and it is certainly important to localize the lesion.The author (Ibrahim, M. M. (1975), British Heart Journal, 37, 868) is justified by his evidence in concluding that the lesion is probably somewhere in efferent sympathetic pathways.The trouble is that the paper produces a powerful deja' vu pheno- menon.Johnson et al. (1966) reported patients inwhom similar tests were done with similar conclusions, and in whom a fall-out of cells in the inter- mediolateral column was found at necropsy.This finding is compatible with degeneration of cell bodies of preganglionic cells.Since then other papers have supported this view and added further evidence.Among these are Vanderhaeghen, Perier and Stemon (1970), Bannister (1971), and Bannister and Oppenheimer (1972).The condition and its association with degeneration elsewhere in the nervous system, and the many reports on the subject are reviewed in the chapter on arterial hypotension in 'Disorders of the Autonomic Nervous System', Johnson and Spalding (1974).