Page 467 - Veterinary Immunology, 10th Edition

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FIG. 15.23 Immunoelectrophoresis of serum from a cat with an
IgM-secreting myeloma. Note that the line of precipitate formed by
the reaction between anti-cat IgM and the myeloma serum is
distorted (bottom well). The line is much thicker than the control,
and it forms two distinct joined arcs as a result of the presence of
large quantities of monoclonal IgM myeloma protein. (Details of this
technique can be found in Chapter 42.) (Courtesy Dr. G. Elissalde.)

Because of the overwhelming commitment of the body's immune

resources to the production of neoplastic plasma cells, as well as the
replacement of normal marrow tissue by tumor cells and the
negative feedback induced by elevated serum immunoglobulins,
animals with myelomas are often immunosuppressed and anemic.

In humans, renal failure and overwhelming infection are the most
common causes of death in myeloma patients.
Affected animals should receive supportive therapy. Antibiotics
can be used to control secondary infections, and fluid therapy

should be administered to combat dehydration resulting from renal
failure. Steroids and diuretics may assist in promoting calcium
excretion. The serum hyperviscosity may be reduced by
plasmapheresis to remove the myeloma protein. The tumor itself

can be treated with specific chemotherapy. The drug of choice is
melphalan, an alkylating agent. Prednisone may be used in
association with melphalan. In unresponsive cases,

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