A. Borczuk et al., DISTINCTIVE CASE - INTESTINAL PSEUDOOBSTRUCTION AND ISCHEMIA SECONDARY TO BOTH BETA(2)-MICROGLOBULIN AND SERUM-A AMYLOID DEPOSITION, Modern pathology, 8(5), 1995, pp. 577-582
We present the case of a 61-year-old man on long-term hemodialysis in
whom early colonic ischemia and pseudo-obstruction were caused by amyl
oid deposition of both the beta(2)-microglobulin and AA type, The ligh
t microscopic diagnosis of amyloidosis was confirmed by Congo red bire
fringence, immunohistochemistry, and electron microscopy. The two type
s of amyloid had separate distributions within the colon, While both t
ypes affected submucosal and serosal blood vessels, the beta(2)-microg
lobulin amyloid also formed large masses that displaced smooth muscle
cells and was associated with Class II major histocompatibility-positi
ve multinucleated giant cells, The pathogenesis of this uncommon occur
rence of two amyloids and the role of chronic inflammation in amyloido
genesis are discussed.