Page 1279 - Veterinary Immunology, 10th Edition

in horses. In these cases, animals lose weight, develop an
VetBooks.ir intermittent fever, and have effusions in multiple joints leading to

stiffness. They have systemic signs of inflammation, including
anemia, leukocytosis, hyperfibrinogenemia, and

hyperglobulinemia. The synovial effusion is sterile, and
immunoglobulins are present in the synovial membrane. The
condition usually resolves with steroid and immunosuppressive
therapy.

Canine Polyarthritis

Dogs may develop several distinct nonerosive polyarthritides,
which can be divided into three major categories: arthritis
associated with SLE, arthritis associated with a myositis, and

idiopathic polyarthritis. Breeds predisposed to polyarthritis include
German Shepherds, Irish Setters, Shetland Sheepdogs, Cocker
Spaniels, and Springer Spaniels. The main clinical features are
stiffness, pyrexia, anorexia, and lethargy. Leflunomide appears to
be an effective alternative to oral corticosteroids for the treatment of

this disease.

Lupus Polyarthritis

Polyarthritis is a common feature of SLE. Diagnosis is contingent on
making a firm diagnosis of lupus. Thus it is necessary to show

multiple-system involvement, a significant titer of serum ANAs,
and immunopathological features consistent with lupus.

Polyarthritis With Polymyositis

A disease characterized by both nonerosive polyarthritis and
polymyositis is recognized in young dogs. Most recorded cases

have been seen in spaniels. The animals are stiff and have painful
joints, fever, lethargy, weakness, muscle atrophy, and muscle pain.
They are negative for both ANA and RF. The arthritis is

symmetrical, involving multiple joints. The animals also have a
symmetrical inflammatory myopathy with myalgia, atrophy, and
muscle contracture. The synovial fluid shows high white cell
counts, especially neutrophils. Muscle biopsies show a neutrophil
or mononuclear cell infiltrate, or both, with muscle fiber atrophy

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