Page 1363 - Veterinary Immunology, 10th Edition

VetBooks.ir Other Secondary Immunodeficiencies

Immunodeficiencies may result from a wide variety of insults to the
body. For example, immunoglobulin synthesis is generally reduced

in individuals with absolute protein loss (patients with the
nephrotic syndrome, heavily parasitized or tumor-bearing
individuals, and patients who have experienced severe burns or
trauma). Stress may result in immunodeficiencies. For example, it is
possible to provoke a combined immunodeficiency syndrome by

chilling newborn puppies for 5 to 10 days. Diverse stressors such as
rapid weaning, sleep deprivation, general anesthesia, prolonged
transportation, and overcrowding are all effective

immunosuppressants. Physical destruction of lymphoid tissues can
result in immunodeficiencies. For example, loss of lymphoid tissue
leading to immunosuppression may occur in tumor-bearing
animals, especially if the tumors themselves are lymphoid in origin
(Fig. 40.12). Adult horses with chronic diarrhea are

immunosuppressed, as reflected by reduced IgA and reduced
lymphocyte responses to mitogens. Some endocrine diseases such
as thyrotoxicosis and diabetes mellitus may also result in

immunosuppression.

1363