Page 1272 - Veterinary Immunology, 10th Edition

infiltrating lymphocytes form lymphoid nodules and germinal
VetBooks.ir centers within the synovia. Amyloidosis, arteritis,

glomerulonephritis, and lymphatic hyperplasia are occasional
complications of rheumatoid arthritis (Fig. 38.8).

FIG. 38.8 A schematic diagram showing how joints are damaged
in rheumatoid arthritis.

It is probable that many different stimuli, especially infectious
agents, trigger rheumatoid arthritis in susceptible animals.

Infectious agents implicated in the human disease include Epstein-
Barr virus (a herpesvirus), parvoviruses, and mycobacteria.. The
composition of the intestinal microbiota also influences the
development of human disease. In domestic mammals, Mycoplasma
hyorhinis, Erysipelothrix rhusiopathiae, and Borrelia burgdorferi each

produce a chronic arthritis that resembles rheumatoid arthritis.
Dogs with rheumatoid arthritis have antibodies to canine distemper
in their synovial fluids, antibodies that are not present in dogs with

osteoarthritis. Immune complexes can be precipitated out of the

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