Page 206 - Veterinary Immunology, 10th Edition

complement and kinin systems, and these too promote
VetBooks.ir inflammation, hypotension, and increased vascular permeability.

The development of DIC carries with it a poor prognosis.

Multiple-Organ Dysfunction Syndrome

(MODS)

MODS is defined as the presence of altered organ function in an
acutely ill animal such that homeostasis cannot be maintained
without intervention. It is usually a sequel to severe sepsis or septic
shock but can also develop as a result of major trauma or anything

else that will induce a systemic inflammatory response syndrome
(Fig. 7.8). It is characterized by hypotension, insufficient tissue
perfusion, uncontrollable bleeding, and organ failure caused by

hypoxia, tissue acidosis, mitochondrial dysfunction and cytopathic
hypoxia, tissue necrosis, and severe local metabolic disturbances.
The reported incidence of MODS in dogs is about 4% in trauma and
50% in sepsis cases. The pathogenesis of MODS is unclear, but it
appears to result from immune system dysregulation and

subsequent mitochondrial dysfunction. The immune system
dysregulation may be due to overregulation of the inflammatory
response and a compensatory antiinflammatory response, as well as

the excessive release of neutrophil reactive oxygen species (ROS),
leading to lethal tissue damage. MODS can affect the liver,
respiratory system, brain, adrenal, the heart, and the kidneys. It
permits bacterial translocation in the gastrointestinal tract and
disseminated intravascular coagulation. Its development is

associated with a poor outcome.

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