Todayโs path rounds are on ๐ฉ๐๐ซ๐ข๐ญ๐จ๐ง๐ข๐ญ๐ข๐ฌ, inspired by a case I had this week!
๐๐ก๐๐ญ ๐ข๐ฌ ๐ข๐ญ?
๐๐๐ซ๐ข๐ญ๐จ๐ง๐ข๐ญ๐ข๐ฌ is inflammation of the ๐ฉ๐๐ซ๐ข๐ญ๐จ๐ง๐๐ฎ๐ฆ, which is the lining of the abdomen. Peritonitis is characterized by large clumps or mats of ๐๐ข๐๐ซ๐ข๐ง, one of the bodyโs main clotting proteins, that are trying to โwall offโ the source of inflammation to try and prevent it from spreading elsewhere in the abdomen. Unfortunately, fibrin is often not very good at controlling the source, and the peritonitis becomes ๐๐ข๐๐๐ฎ๐ฌ๐ throughout the whole abdomen.
๐๐ก๐จ ๐ ๐๐ญ๐ฌ ๐ข๐ญ?
Any species can get this!
๐๐ก๐๐ญ ๐๐๐ฎ๐ฌ๐๐ฌ ๐ข๐ญ?
The basic underlying problem causing peritonitis is some sort of foreign material or fluid in the abdomen. Some common causes include leakage of gastrointestinal contents, bile, pancreatic secretions, or bacterial infection.
๐๐ก๐ฒ ๐ข๐ฌ ๐ญ๐ก๐ข๐ฌ ๐ ๐ฉ๐ซ๐จ๐๐ฅ๐๐ฆ?
One of the first issues with a widespread peritonitis is that it can cause ๐ฉ๐๐ซ๐๐ฅ๐ฒ๐ญ๐ข๐ ๐ข๐ฅ๐๐ฎ๐ฌ, or no movement of the intestines, which leads to constipation. Why would the body do this? Because it is trying to prevent the movement of the intestines from spreading the foreign material around the abdomen! Neat.
Unfortunately this neat feature does have some consequences. Without having adequate flow through the gastrointestinal tract, a lot of fluid, electrolytes and nutrients become stuck there. This can lead to issues with maintaining ๐๐๐ข๐-๐๐๐ฌ๐ ๐๐๐ฅ๐๐ง๐๐, which can ultimately cause death if left untreated. If there are bacteria involved in the infection, the bacteria can proliferate in the abdomen and produce toxins. These toxins can then move into the bloodstream and cause death of the animal. Ultimately, peritonitis is generally a pretty sad time for the animal.
If the animal manages to survive the initial stages of peritonitis, itโs still not out of the woods yet! Fibrin has a โfunโ feature of organizing and maturing into ๐๐ข๐๐ซ๐จ๐ฎ๐ฌ ๐๐๐ก๐๐ฌ๐ข๐จ๐ง๐ฌ after 3-4 days, which are essentially giant bands of scar tissue. Remember how this fibrin is all over the abdomen? When it becomes fibrous, it often can tighten around the intestines causing obstruction. This leads to similar problems as the paralytic ileus described earlier. Sometimes science is cruel 
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐๐ข๐๐ ๐ง๐จ๐ฌ๐๐?
Peritonitis can be diagnosed by doing an ๐๐๐๐จ๐ฆ๐ข๐ง๐จ๐๐๐ง๐ญ๐๐ฌ๐ข๐ฌ, where they stick a needle into the abdomen and collect a fluid sample. From this sample, the veterinarian can look for feed material (indicating a gastrointestinal rupture), bile, urine, etc. to try and identify the cause of the peritonitis. Peritonitis fluid can also be visualized on ultrasound, however it may not give you specific information about the cause of the peritonitis.
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐ญ๐ซ๐๐๐ญ๐๐?
The main treatment requires fixing whatever caused the peritonitis initially, followed by supportive care measures like ๐ฉ๐๐ซ๐ข๐ญ๐จ๐ง๐๐๐ฅ ๐ฅ๐๐ฏ๐๐ ๐ (rinsing out the abdomen), antibiotics and anti-inflammatory medications. Unfortunately in our large animal species, this is extremely difficult, so a lot of considerations about the animalโs quality of life have to be incorporated into developing a treatment plan.
๐๐ก๐จ๐ญ๐จ๐ฌ
1-5) Examples of peritonitis! Look at all that fibrin having a party in the abdomen.
๐๐จ๐ฎ๐ซ๐๐๐ฌ
Maxie, G. Jubb, Kennedy and Palmerโs Pathology of Domestic Animals, Volume 2. Sixth Edition.
Wittek, T. Peritonitis in animals. Merck Veterinary Manual 2020.
Photos 1-5 courtesy of University of Calgary Diagnostic Services Unit.
