Intramural hematoma in the jejunum of a mare.

This research article investigates a case where a mare was obstructed by an intramural hematoma in the small intestine, hypothesizing that it may have been caused by issues relating to blood vessels and parasites.

Research Context

• The study revolves around a case of intestinal obstruction in a mature mare, caused by an intramural hematoma. An intramural hematoma is a collection of blood within the wall of the intestine.
• This particular hematoma, measuring about 40 cm, was located in the distal segment of the jejunum—the middle section of the small intestine.

Initial Treatment and Consequences

• The mare’s immediate complication was colic, a severe abdominal pain commonly observed in horses.
• To treat the obstructed intestine, the involved segment was surgically removed, and an end-to-end anastomosis was performed. This procedure connects the two remaining ends of the intestine to maintain normal function.
• Recovery from the surgery was complete, but four years later, the mare suffered from another episode of colic. This time it was triggered by incarceration and volvulus, a twisting of the distal portion of the jejunum. The researchers believe that fibrous abdominal adhesions—bands of scar tissue that stick tissues and organ together—were involved.

Investigating the Cause of the Hematoma

• Despite the surgical interventions and the mare’s recovery, the underlying cause of the hematoma was not definitively identified.
• The researchers considered the rupture of a blood vessel within the intestinal wall as a potential cause. They speculated that the damage might have been instigated by the migration of Strongylus vulgaris larvae. Supporting this hypothesis, an intensive eosinophilic infiltrate was found histologically within the region. Eosinophilic infiltrates are usually suggestive of parasitic infections or allergic reactions.
• Another conjecture was that the rupture might have resulted from a blunt force trauma to the abdomen. However, this was deemed unlikely based on the available information.
• According to the researchers, previous reports of intramural hematomas in horses have only been associated with the small colon—making this case involving the jejunum relatively unusual.