Page 106 - Textbook of Pathology, 6th Edition

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SECTION I

Figure 4.14 Gross patterns of amyloidosis of the spleen.

Congo red staining showing red pink colour and Grossly, the liver is often enlarged, pale, waxy and firm.
polarising microscopy showing apple-green birefringence Histologically, the features are as under (Fig. 4.17):
General Pathology and Basic Techniques
confirms the presence of amyloid (Fig. 4.13). The amyloid initially appears in the space of Disse
(the space between the hepatocytes and sinusoidal
Amyloidosis of Spleen endothelial cells).
Amyloid deposition in the spleen, for some unknown
reasons, may have one of the following two patterns
(Fig. 4.14):
1. SAGO SPLEEN. The splenomegaly is not marked and
cut surface shows characteristic translucent pale and waxy
nodules resembling sago grains and hence the name.
Microscopically, the amyloid deposits begin in the walls
of the arterioles of the white pulp and may subsequently
replace the follicles.
2. LARDACEOUS SPLEEN. There is generally moderate
to marked splenomegaly (weight up to 1 kg). Cut surface
of the spleen shows map-like areas of amyloid
(lardaceous-lard-like; lard means fat of pigs) (Fig. 4.15).
Microscopically, the deposits involve the walls of splenic
sinuses and the small arteries and in the connective tissue
of the red pulp (Fig. 4.16). Confirmation is by seeing
Congophilia in Congo Red staining and demonstration
of apple-green birefringence under polarising microscopy
in the corresponding positive areas.

Amyloidosis of Liver
In about half the cases of systemic amyloidosis, liver Figure 4.15 Lardaceous amyloidosis of the spleen. The sectioned
involvement by amyloidosis is seen. surface shows presence of plae waxy translucency in a map-like pattern.