Mesometrial hemotoma causing peritonitis
Keywords: equine, hematoma, mesometrium, fatal, foaling, peritonitis
An unusual variation of a mesometrial hematoma caused by a ruptured uterine artery.
In this case, the hematoma spread more caudally than is common. Eventually its contents seeped into the peritoneal cavity through the site marked by the forceps in this image. In addition, a small thread-like fistula existed between the caudal area of the cervix and the most caudal part of the hematoma. This fistula may have formed as a result of cervical laceration during foaling. A long blunt probe was passed through the fistula to reveal its location in this image.
Image size:1618 x 1240px
Several days after foaling, the mare developed severe acute peritonitis and died. It was concluded that infection had spread into the hematoma from the injury in the cervix (lowest red arrow), through the hematoma and into the peritoneal cavity (upper red arrow & forceps).
Because of the pressure required to dissect connective tissue and form this large hematoma, it was remarkable that blood had not burst into the peritoneal cavity at the time of foaling. Perhaps bleeding had been intermittent, allowing a degree of coagulation. This would have permitted the hematoma itself to act like a valve, preventing blood from entering the peritoneal cavity where the forceps are shown here. Also, there were no obvious signs of putrefaction in the blood clot although it was clearly the only source of infection for the peritonitis that ensued. Cytology of the coagulum was not performed; an important omission in this case. In retrospect, it would probably have revealed many bacteria.
For consideration by clinicians:
Routine examination of the mesometrium by ultrasonography immediately after foaling is seldom if ever done. The author is in favor of routine examination of the vagina after foaling to detect tears into the peritoneal cavity. However, some owners object to this practice on the basis that it could interfere with dam-offspring bonding. If an owner allows this, it may be good practice to examine the mesometrium and pelvis for hematomas at the same time. If a hematoma is detected via ultrasonography, one could consider prophylactic treatment with antibiotics and tetanus toxoid. |
