Small intestinal herniation through the broad ligament in a mare outside of the gestation period – a case report

A Furioso-North Star mare, aged 8 years, was examined for colic signs. The mare had a history of dystocia and post partum vaginal lacerations, acute endometritis and laminitis approximately one year before the admission for colic. Signs of persistent abdominal pain, moderate distended abdomen, non-passage of manure, fever, tachycardia, tachypnoea, congested mucus membranes, and “toxic line” were recorded. No intestinal borborygmi were present in the four quarters of the abdomen. On rectal examination, the colon, the ventral band of the caecum, the right ovary and the uterine horn were palpated on the right side of the abdomen. The spleen, the nephrosplenic ligament, the left ovary and a firm, distended and painful small intestine (SI) loop were palpated on the left side. The left uterine horn and the adjacent broad ligament were not detectable. Percutaneous abdominal ultrasound evaluation revealed a large amount of fluid in the abdominal cavity, SI distention and absence of peristalsis. Abdominocentesis yielded approximately 20 ml of red-tinged peritoneal fluid with increased mean protein concentration (5.2 mg/dl), white blood cell count (12,550 cells/μl), and lactate (14 mmol/dl). A presumptive diagnosis of SI strangulation was made. Surgical resection of the affected intestinal loops was recommended. Due to poor prognosis and financial limitations, the mare was euthanized. Post mortem macroscopic diagnosis was a herniation of 3 metres of the mid-jejunum through the left mesometrium, resulting in a complete and complicated strangulation. To prevent this type of SI strangulation, we recommend transrectal palpation of the urogenital tract (including the broad ligament) after foaling. If a defect is identified, we recommend flank laparoscopy for correction. Colic, small intestine herniation, mesometrium, nonpregnant mare Horses are susceptible to colic due to digestive tract particularities (Datt and Usenik 1975). Small intestinal strangulating obstructions (SISO) are encountered in 19–32% of cases (van den Boom and van der Velden 2001). Strangulated obstructions of small intestine (SI) loops are the result of luminal blockage and concurrent compromise of the blood supply, followed by intestinal ischaemia, gangrene and/or rupture of the affected intestinal loops (Withers and Mair 2008). The most frequent causes of SISO include pedunculated lipomas, epiploic foramen entrapment, incarceration in inguinal/scrotal hernia, volvulus, incarceration in mesenteric rent, incarceration by fibrous band/adhesions, intussusception, incarceration in the gastrosplenic ligament, diaphragmatic hernia and incarceration in the umbilical hernia or omental hernia (Withers and Mair 2008). In mares, SISO have also been associated with pregnancy, when the jejunum is entrapped over the broad ligament of the uterus (Santschi 2009). The broad ligament is a peritoneal fold, subdivided into the mesosalpinx, mesovarium and mesometrium, which attaches the oviduct, ovary, and uterine horns/body, respectively, to the abdominal and pelvic walls (Ginther 1992). During pregnancy, a rent in the broad ACTA VET. BRNO 2018, 87: 331–337; https://doi.org/10.2754/avb201887040331 Address for correspondence: Cristian Crecan Anaesthesiology and Surgery Department Faculty of Veterinary Medicine University of Agricultural Sciences and Veterinary Medicine 3-5 Manastur street, Cluj-Napoca, 400372, Romania Phone: +4 0732 556 462 E-mail: dr.cristicrecan@gmail.com http://actavet.vfu. cz/ ligament can be created by the kicking motions of the foal or by the foal repositioning for parturition in the last month of gestation (Ginther 1998). Up to date, there have been only 4 cases of jejunal herniation through a rent in the broad ligament reported in the literature. The first was briefly mentioned in a study without stating the pregnancy status of the mare (Tennant et al. 1975). Two cases were reported in pregnant mares, one of which was described as a SI herniation through the mesometrium at 8 month of gestation (Becht and McIlwraith 1980), whereas the other was only briefly mentioned in a study by Freeman and Schaeffer (2011). The forth case was a SI herniation through the mesometrium in a nonpregnant mare with a history of 2 normal pregnancies (Steward et al. 2018). Given the rarity of this lesion, this case report describes in detail the clinical signs and pathological outcomes in a nonpregnant mare with SI herniation through the broad ligament, providing novel insights in diagnosis, possible treatment options and prevention. Case description Case history In March 2015, a Furioso-North Star mare aged 8 years and weighing 700 kg was referred to the Equine Clinic of the Veterinary Medicine Faculty, Cluj-Napoca, Romania, for sudden onset of severe colic signs of 10 hours’ duration. The mare had a history of dystocia caused by an oversized foetus and followed by severe post partum vaginal lacerations, acute endometritis and laminitis approximately one year before the current admission. The uterine involution was followed by a transrectal ultrasound examination performed twice at a 9-day interval. When the involution was complete, the left uterine horn remained bigger in size compared to the contralateral horn, which was of normal size. The full recovery period, including vaginal lacerations and laminitis, lasted around four months. The mare was not bred again.