Clostridioides (Clostridium) difficile-associated disease, epiploic foramen entrapment, and gastric rupture in a Thoroughbred racehorse: case report and literature review.

Epiploic foramen entrapment (EFE) is a common cause of small intestinal colic in horses and may lead to intestinal strangulation. Strangulating intestinal obstruction impairs the gastrointestinal outflow and can lead to secondary gastric rupture and endotoxemia. Clostridioides difficile can cause enterotyphlocolitis with colic in horses of all ages, and the process is commonly referred to as C. difficile-associated disease (CDAD). Here we report the results of the postmortem examination of a 7-y-old Thoroughbred racehorse with concurrent CDAD, EFE, and gastric rupture that was euthanized following a history of colic over several days. A segment of distal jejunum and proximal ileum had passed through the epiploic foramen, and the intestinal wall was thickened and dark-red. The remaining small intestinal loops were distended and filled with blood-tinged contents. Peritonitis had resulted from escape of gastric contents into the abdominal cavity through a tear in the major curvature of the stomach. Histologically, the incarcerated segment had acute transmural hemorrhage with congestion and mucosal necrosis; neutrophilic infiltrates with fibrin thrombi were in the mucosa of the non-incarcerated small intestinal segments. C. difficile toxins were detected in the small intestinal contents, and C. difficile was isolated from the small intestine, colon, and cecum.

Equine colic associated with small intestinal epiploic foramen entrapment.

Intestinal epiploic foramen entrapment (EFE) is an important differential diagnosis in horses with colic, but disappointing short- and long-term outcomes are reported in the scientific literature. Many horses are euthanased during surgery due to a predicted poor prognosis or due to uncontrollable intraoperative haemorrhage. The ileum is involved in the majority of cases. Several risk factors for the development of EFE are described; crib-biting/windsucking being the most important one. The recurrence rate of EFE is low despite the described risk factors, probably due to spontaneous closure of the EF after EFE colic surgery in about 40% of the cases. Safe laparoscopic techniques to obliterate the EF preventively in horses at risk or as part of surgical management of EFE at laparotomy are described. Methods for improved outcomes including utilising recently gained anatomical insights of the region while manipulating entrapped intestines, critical revision of anastomosis techniques and avoiding the occurrence of post-operative reflux are discussed.

Mesh closure of epiploic foramen by ventral laparotomy in 17 horses with entrapment.

BACKGROUND: Epiploic foramen entrapment (EFE) of small intestine is a severe cause of strangulating small intestinal obstruction (SSI) with long-term survival seeming lower than for other causes of SSI in horses. Different techniques via laparoscopy or laparotomy for epiploic foramen (EF) closure have been developed. METHODS: This study describes a technique of peroperative mesh closure of the EF in clinical cases and their long-term follow up. RESULTS: In the study period of 5.5 years, 36 horses were admitted to the clinic with EFE. Of these, 17 horses had peroperative mesh closure, with resection anastomosis in 4 cases and enterotomy in 4 other cases. Fifteen of these survived to discharge. Long-term follow-up (one to three years, median three years) was favourable in all 15 horses not showing recurrence of EFE nor other related signs of colic. Laparoscopic evaluation of the EF was performed in two cases and showed integration of the mesh. One horse was euthanased 3.5 years after mesh placement for an unrelated cause and the mesh was well adherent obliterating the EF. CONCLUSION: Mesh closure of EF during emergency coeliotomy did not cause short-term complications even in horses with resection or enterotomy and may reduce the risk of recurrence of EFE in horses.

Proteinase Activated Receptor 4 in the Jejunum of Healthy Horses and of Horses With Epiploic Hernia.

Proteinase activated receptor 4 (PAR4) in the gastrointestinal tract is involved in the regulation of inflammation and pain pathways. The aim of the present study was to evaluate the distribution and expression of PAR4 in the jejunum of healthy horses and in the pathologic tracts from horses undergoing surgery for herniation of the small intestine through the epiploic foramen. Eight healthy horses (Group H) and eight horses with epiploic hernia (Group EH) were included; the jejunum samples were collected at the slaughter or intraoperatively after enterectomy, respectively. To evaluate PAR4 expression in sections of the jejunum, immunofluorescence, western blot and quantitative polymerase chain reaction (qRT-PCR) were performed. Immunohistochemistry of PAR4 in the jejunum of the healthy horses showed that receptors are predominantly expressed in the immune cell population scattered throughout the lamina propria of the mucosa and in the submucosa. Quantitative PCR data demonstrated that PAR4 mRNA was detectable in all of the samples analyzed without any difference between the H and the EH groups, however the PAR4 protein level was significantly lower in the jejunums of the EH horses. In the Group EH horses, PAR4 immunoreactivity was mainly expressed in the mast cells and was extensively distributed in the sierosa. In the lamina propria of mucosa of Group EH, leukocytes were less abundant than in Group H. In this study, the distribution and expression of PAR4 in the jejunums of the healthy horses and in those with spontaneous occurring epiploic hernia was demonstrated.

Proteinase-activated receptor 2 distribution and expression in equine small intestine tracts following herniation through the epiploic foramen.

Proteinase-activated receptor 2 (PAR2) is a G-protein-coupled receptor for trypsin and mast cell tryptase; it is highly expressed at the intestinal level with multiple functions, such as epithelial permeability and intestinal motility. The aim of the study was to evaluate the distribution and expression of proteinase-activated receptor 2 in the small intestine during herniation through epiploic foramen. In this prospective clinical study, eight horses admitted for colic and which underwent exploratory laparotomy were considered. During surgery, the jejunum or the ileum was sampled by enterectomy. Morphological examination (histology, PAR2 immunohistochemistry) and molecular biology analysis (western blot and quantitative polymerase chain reaction) were carried out on the resected intestinal samples. The Marginal Injured Tracts (MITs) and Central Injury Tracts (CITs) were defined as the oral and caudal marginal segments of the resected bowel tract and as the geometric centre of the intestinal ischaemic lesion length, respectively. The PAR2 immunoreactivity was particularly evident in the epithelial cells, with higher immunoreactivity in the MIT rather than in the CIT. Moreover, a different immune localisation was observed in the MITs at the cell membrane level and in the CITs in the cytoplasm. No statistical difference was observed in PAR2 mRNA and protein (44kDa) expression between the MIT and the CIT. The PAR2 protein content in the intestinal tracts which were removed from horses with herniation was lower when compared with the control animals. This study provided data concerning the PAR2 presence and distribution in horses with intestinal herniation through the epiploic foramen.

Foramen epiploicum mesh closure (FEMC) through a ventral midline laparotomy.

BACKGROUND: Preventive laparoscopic closure of the epiploic foramen (EF) has previously been described, but methods for EF closure during laparotomy for treatment of colic are lacking. OBJECTIVES: To describe the foramen epiploicum mesh closure (FEMC) technique through a ventral midline laparotomy in horses under general anaesthesia and its outcome. STUDY DESIGN: Terminal surgical experiment and in vivo study. METHODS: In a pilot study, a standard ventral midline laparotomy was performed under general anaesthesia in 10 experimental horses and a three-dimensional expandable diabolo-shaped mesh construct was manually introduced through the EF into the omental vestibule. The laparotomy incision was routinely closed after which the horses were subjected to euthanasia. Subsequently, the cadavers were extensively manipulated and finally mesh position was verified during necropsy. Thereafter, a ventral midline laparotomy, with simulation of abdominal manipulations during colic surgery was performed on six experimental horses. A three-dimensional expandable diabolo-shaped mesh with a radiological marker was introduced as in the pilot study. Clinical and laboratory parameters were recorded during the post-operative period. Four weeks after the intervention, abdominal radiography and laparoscopy were performed in all six horses. RESULTS: Insertion of all 16 diabolo-shaped mesh constructs during laparotomy was uneventful. The 10 mesh constructs of the pilot study were positioned correctly at necropsy. No post-operative clinical or laboratory parameter alterations were noticed in the other six horses, apart from a transient leucocytosis and an increase in serum amyloid A. Abdominal radiography at 4 weeks revealed consistent positioning of the mesh marker. Laparoscopy confirmed that all six EFs were closed, without intestinal adhesions. MAIN LIMITATIONS: Mesh insertion in clinical cases and during clean contaminated surgery was not investigated. CONCLUSION: The FEMC technique via laparotomy provides a fast, simple and reliable procedure to obliterate the EF and may be useful during EFE surgery to prevent recurrence of the disease, avoiding a subsequent laparoscopic procedure.

Encarceramento do intestino delgado em forame epiploico em equinos com hábito de aerofagia: relato de caso / Entrapment of the small intestine in the epiploic foramen in crib-biting horses: case report

São relatados quatro casos de encarceramento de forame epiploico (EFE), entre os casos: três machos e uma fêmea; dois da raça Quarto de Milha, um SRD e um Brasileiro de Hipismo; idade média de 11 anos; altura média de cernelha de 160,5cm; massa corporal média de 465kg. Todos os animais possuíam o hábito de aerofagia. A presença de refluxo enterogástrico e intestino delgado distendido à palpação transretal foi variável na dependência do segmento intestinal aprisionado. À laparotomia exploratória constataram-se: dois casos de aprisionamento jejunoileal; um de jejuno; e o outro de íleo. Todos os animais apresentaram EFE da esquerda para a direita, representando o sentido horário. Apenas o animal que apresentava o íleo aprisionado sobreviveu; os demais foram submetidos à eutanásia no período transoperatório devido à extensa isquemia intestinal e às lesões vasculares decorrentes da manobra de redução. A aerofagia é o fator de risco que apresenta maior correlação positiva com o EFE, fato corroborado pelos casos apresentados. Apesar de ser descrito um bom prognóstico para o EFE na literatura, foi obtido um desfecho ruim entre os casos atendidos, e salienta-se que a extensão da lesão e o sangramento da veia porta no transoperatório contribuíram para esse resultado.(AU)

Four cases of epiploic foramen entrapment (EFE) are reported. Among the cases, three males and one female, two Quarter Horses, one mixed breed and one Brazilian Equestrian, aged between 3 to 20 years, mean 11 years. The average height was 160.5cm and 465kg. All horses had a previous record of crib-biting habit. The presence of enterogastric reflux and small intestine distended loops in transrectal palpation was variable in dependence of the trapped segment. In surgical exploration were identified two cases of jejunum and ileum entrapped, one of the ileum and one of jejunum. All animals showed EFE from left to right. The horse that had trapped the ileum has survived. The others were euthanized due to the extent of injury or rupture of large vessels during surgical reduction. Although there are many notes of possible risk factors for EFE occurrence, cribbing is the risk factor that has the highest positive correlation with EFE. This appointment was confirmed by the cases presented. Despite being described a good prognosis for the EFE, a bad outcome was achieved among the cases, and stresses that the extent of the injury and bleeding from the portal vein contributed to this outcome.(AU)

Laparoscopic Repair of Foramen of Winslow Hernia.

Foramen of Winslow hernia is a rare surgical entity with very few reported cases in literature. Preoperative diagnosis used to be difficult but with emerging computed tomography technology, diagnosing this internal abdominal hernia has become easier. We present an unusual case report of foramen of Winslow hernia in a 77-year-old patient who presented with severe abdominal pain. The patient underwent laparoscopic repair of the hernia and recovered well postoperatively. This presentation of symptoms in a 77-year-old male is unusual and laparoscopic management of foramen of Winslow hernia presents an interesting and challenging management scenario.

Development of a new laparoscopic Foramen Epiploicum Mesh Closure (FEMC) technique in 6 horses.

REASONS FOR PERFORMING STUDY: Epiploic foramen entrapment (EFE) is, based on the number of reports in the literature, a relatively important life-threatening cause of colic in horses that could be prevented by closing the epiploic foramen (EF) in horses at risk of developing EFE. OBJECTIVES: To describe the laparoscopic foramen epiploicum mesh closure (FEMC) technique and its outcome. STUDY DESIGN: Descriptive experimental study. METHODS: The EF of 6 horses was closed with the FEMC technique. A diabolo-shaped constructed mesh was introduced into the omental vestibule through the EF under laparoscopic visualisation in the standing sedated horse. Clinical and laboratory parameters were recorded during the post operative period. Four weeks after the intervention, repeat laparoscopy was performed in all horses. Three horses were subjected to euthanasia one, 2 and 3 months after the intervention, and were examined on necropsy and histopathology. The remaining 3 horses were followed clinically for 6 months. RESULTS: The 6 FEMC procedures were performed successfully in a median surgery time of 22 min (range 18-27 min). One horse was treated for large colon impaction in the immediate post operative period. On repeat laparoscopy at 4 weeks all 6 EFs were closed and no undesired adhesions were identified. This was confirmed on gross and histopathological examination of the 3 horses that were subjected to euthanasia. The 3 remaining horses were clinically normal in the 6-month post operative observation period. CONCLUSIONS: This FEMC technique provides a fast, simple, reliable and safe procedure to obliterate the EF and may be useful in horses at risk for EFE.

Anatomy of the vestibule of the omental bursa and epiploic foramen in the horse.

REASONS FOR PERFORMING STUDY: Epiploic foramen entrapment (EFE) is a common cause of colic in horses and available anatomical descriptions of this foramen and the associated vestibule of the omental bursa tend to be inconsistent, contradictory and inaccurate. OBJECTIVES: To describe the anatomy of the vestibule of the omental bursa and epiploic foramen. STUDY DESIGN: Dissection of 21 fresh equine cadavers shortly after euthanasia. METHODS: The anatomy of the vestibule of the omental bursa, epiploic foramen and related structures in the cranial abdomen were examined in situ and after removal from the abdomen. Photographs were taken and illustrations rendered to bring the relationship of the different folds, ligaments and organs involved into a 3D concept. RESULTS: The entrance into the vestibule and the passageway through it to the epiploic foramen is bounded by the gastropancreatic fold dorsally, caudally and ventrally. This fold constitutes the caudoventral boundary of the epiploic foramen along with the portal vein cranially and ventrally. The craniodorsal boundary of the epiploic foramen is formed by the caudate lobe of the liver. CONCLUSIONS: The gastropancreatic fold plays a more important role in the anatomy of the vestibule of the omental bursa and the epiploic foramen than has been documented in the most widely used anatomy textbooks written in English. Because of the importance of EFE in horses, information from this study about the relevant anatomy could provide a first step towards improved methods for treatment and laparoscopic prevention of these diseases.

A topographic anatomical study of the equine epiploic foramen and comparison with laparoscopic visualisation.

REASONS FOR PERFORMING STUDY: There are no previous studies correlating the anatomy of the equine epiploic foramen and its defining structures with laparoscopic images. OBJECTIVES: The purpose of this study was to describe the precise anatomy of the epiploic foramen and omental vestibule, to quantify the dimensions of the epiploic foramen and to relate these findings to laparoscopic images. STUDY DESIGN: Descriptive study of cadaver material and laparoscopic images. METHODS: Thirty-two horses subjected to euthanasia for reasons unrelated to colic were studied. Two cadavers were used to make vascular casts of the coeliac artery and portal vein. In 30 cadavers the epiploic foramen and omental vestibule were cast with a polyurethane prepolymer immediately after euthanasia. The cast served as a landmark during dissection and the circumference of the epiploic foramen was measured from these casts. Histology was performed on structures defining the epiploic foramen in 2 horses. Laparoscopic images from 6 standing right flank procedures were reviewed. RESULTS: The defining structures of the epiploic foramen and omental vestibule are the hepatoduodenal ligament, hepatogastric ligament and the gastropancreatic and hepatopancreatic folds. The hepatoduodenal ligament has a secondary fold which forms the ventral border of the epiploic foramen, consisting of a central connective tissue core of mainly elastin fibres. The hepatic artery for part of its course is incorporated in the hepatoduodenal ligament. All these structures are clearly visible laparoscopically. The mean circumference of the epiploic foramen is 11.6 ± 2.6 cm and its circumference is positively correlated with body weight but is unrelated to age or gender. CONCLUSIONS: Several clinically relevant structures delineate the epiploic foramen. Its defining structure consists, in part, of elastin fibres. Anatomical and laparoscopic knowledge may assist surgeons in developing interventions to treat diseases involving the epiploic foramen.