著明な起立性低血圧を伴った原発性アミロイドーシスの1例

A case of primary amyloidosis with orthostatic hypotension

　原発性アミロイドーシスに起立性低血圧が合併することは広く知られている^1）。しかし，その成因に関しては，循環血漿量の減少^2），末梢血管へのアミロイド沈着3），自律神経節へのアミロイド沈着や末梢交感神経終末でのカテコラミンの枯渇^4〜6）などが報告されているが，一定の見解は得られていない。

　今回，われわれは著明な起立性低血圧を伴った原発性アミロイドーシスの1例に種々の自律神経機能検査を行い，起立性低血圧の機序として広範な自律神経障害が関与している成績を得たので報告する。

Autonomic nerve function was investigated in a patient with primary amyloidosis and orthostatic hypotension. There was a striking reduction of beat-to-beat variation in heart rate with deep brea-thing. Heart rate responses to phenylephrine and atropine were absent. Pressor response to phenyle-phrine was normal. Increments of heart rate during 60 passive tilt and sustained handgrip were diminis-hed. Vasoconstrictor responses to Valsalva maneuv-er, cold stimulation and passive tilt were absent. Extensive amyloid infiltration of peripheral autono-mic nervous system was present at autopsy.

These results suggest that orthostatic hypotension in primary amyloidosis may occur as a result of a diffuse autonomic neuropathy.