Page 108 - Textbook of Pathology, 6th Edition

92 Amyloidosis of Heart and gingival biopsies are the common sites for diagnosis of
systemic amyloidosis. The deposits are initially located
Heart is involved in systemic amyloidosis quite commonly, around the small blood vessels but later may involve adjacent
more so in the primary than in secondary systemic layers of the bowel wall. Tongue may be the site for tumour-
amyloidosis. It may also be involved in localised form of forming amyloid, producing macroglossia.
amyloidosis (senile cardiac and AANF). In advanced cases,
there may be a pressure atrophy of the myocardial fibres and Other Organs
impaired ventricular function which may produce restrictive
cardiomyopathy. Amyloidosis of the heart may produce Uncommonly, the deposits of amyloid may occur in various
arrhythmias due to deposition in the conduction system. other tissues such as pituitary, thyroid, adrenals, skin, lymph
SECTION I
nodes, respiratory tract and peripheral and autonomic
Grossly, the heart may be enlarged. The external surface nerves.
is pale, translucent and waxy. The epicardium,
endocardium and valves show tiny nodular deposits or PROGNOSIS OF AMYLOIDOSIS
raised plaques of amyloid. Amyloidosis may be an incidental finding at autopsy or in
Microscopically, the changes are as under: symptomatic cases diagnosis can be made from the methods
Amyloid deposits are seen in and around the given above, biopsy examination being the most important
coronaries and their small branches. method. The prognosis of patients with generalised
In cases of primary amyloidosis of the heart, the amyloidosis is generally poor. Primary amyloidosis, if left
deposits of AL amyloid are seen around the myocardial untreated, is rapidly progressive and fatal. Therapy in these
fibres in ring-like formations (ring fibres). cases is directed at reducing the clonal marrow plasma cells
In localised form of amyloid of the heart, the deposits as is done for treatment of multiple myeloma. For secondary
are seen in the left atrium and in the interatrial septum. reactive amyloidosis, control of inflammation is the mainstay
of treatment. Secondary amyloidosis has somewhat better
outcome due to controllable underlying condition.
Amyloidosis of Alimentary Tract
Renal failure and cardiac arrhythmias are the most
Involvement of the gastrointestinal tract by amyloidosis may common causes of death in most cases of systemic
occur at any level from the oral cavity to the anus. Rectal amyloidosis.

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General Pathology and Basic Techniques