Background: In humans and experimental animals, disseminated intravascular coagulation (DIC) causes fibrin deposition in several organs, which eventually leads to ischemia and multiorgan failure.
Hypothesis: Horses who died or were euthanized for severe gastrointestinal disorders could have fibrin deposits in different tissues.
Animals: Tissue-organ samples collected during postmortem examinations on 66 colic horses with poor prognoses (eg, severe intestinal ischemia, enteritis, peritonitis), from 11 colic horses with good prognoses (eg, large-colon obstruction or displacement), and from 16 slaughter horses.
Methods: Tissue samples (kidney, lung, liver) were stained with hematoxylin and eosin, and phosphotungstic acid hematoxylin for a blinded histologic examination. A fibrin score (grades 0 to 4) was established for each tissue sample and for each horse.
Results: Fibrin deposits were found in tissue specimens of 11 of 27 of horses (40.7%) in the ischemic group, 8 of 21 in the enteritis group (38.1%), and 7 of 18 in the peritonitis group (39.0%), whereas none of the horses in the obstructive group (n = 11) and only 1 horse in the slaughter group (n = 16) had fibrin deposits in their tissues. In addition, the mean fibrin score values for the ischemic, enteritis, and peritonitis groups (1.3 +/- 1.7, 1.1 +/- 1.6, and 0.9 +/- 1.3, respectively) were statistically higher than those for the obstructive and slaughter groups (0.0 +/- 0.0 and 0.1 +/- 0.5, respectively). The largest fibrin deposits were found in the lungs.
Conclusions and clinical importance: Horses with severe gastrointestinal disorders have fibrin deposits that are consistent with capillary microthrombosis, multiorgan failure, and DIC.