Duodenitis/proximal jejunitis (DPJ) in a horse
By Andrés de la Concha-Bermejillo, DVM, PhD
A 5-year-old Andalusian stallion was presented for necropsy at the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) after being euthanatized due to a history of colic, profuse nasogastric reflux, non-response to treatment, and poor prognosis.
Upon opening the abdomen at necropsy, the stomach was found to be severely distended with gas. The duodenum and proximal jejunum were moderately distended. The right and left dorsal and ventral colon were very small and attenuated. The content of the stomach consisted of large amounts of free gas and approximately 1.7 gallons of green, watery fluid with small amounts of vegetal material. The mucosa of the stomach was severely congested. The duodenum and jejunum were filled with large amounts of fluid and the mucosa was hyperemic. The colon contained a small to moderate amount of dehydrated or pasty green vegetal digest and small amounts of small grain. There were no other significant gross lesions recognized.
Based on the necropsy findings and the clinical history, a diagnosis of duodenitis/proximal jejunitis (DPJ) was established. Other names given to this disease include anterior enteritis, proximal enteritis, acute ileus syndrome, acute gastric dilatation, cranial enteritis, fibrinonecrotic duodenitis/enteritis or jejunitis, gastroduodenitis and hemorrhagic fibrinonecrotic duodenitis-proximal enteritis.
DPJ is an acute sporadic gastrointestinal disease of horses, clinically characterized by depression, decreased or absent intestinal motility, colic, ileus, endotoxemia, and nasogastric reflux, the latter due to fluid accumulation in the stomach and proximal small intestine.
Approximately 30% of DPJ cases develop laminitis. Other complications include cardiac arrhythmias, infarction of the heart and kidney, increased liver enzymes and total bilirubin, septic peritonitis, and aspiration pneumonia.
Microscopic lesions consist of mild to severe hyperemia and edema of the intestinal mucosa and submucosa, exfoliation of the intestinal epithelium, areas of hemorrhage, and infiltration of neutrophils in the intestinal mucosa, submucosa, muscularis, and serosa.
In the majority of cases, the cause cannot be determined. Salmonella spp. or Clostridium perfringens can be isolated from gastric reflux. However, in the majority of cases, these bacteria have not been isolated consistently, and many horses with documented colonization with these organisms do not develop DPJ. Other possible etiologies that have been suggested include mycotoxins and ischemia associated with use of nonsteroidal anti‐inflammatory drugs, but the evidence is scarce.
Recently, toxigenic strains of Clostridium difficile have been isolated from the reflux of horses with DPJ, suggesting that C. difficile could be a cause of DPJ.
Some of the predisposing risk factors that have been proposed include stress from foaling or changes in training routine and possibly diet.
In conclusion, DPJ should be considered a syndrome with multiple etiologies that may result in similar clinical and pathologic findings, with toxins of C. difficile being one of the potential causes of this syndrome.
For questions about this article, please contact Dr. Andres de la Concha, veterinary pathologist at (979) 845-3414. For more information about TVMDL’s test offerings, visit tvmdl.tamu.edu.
Arroyo LG, Costa MC, Guest BB, Plattner BL, Lillie BN, Weese JS. Duodenitis-Proximal jejunitis in horses after experimental administration of Clostridium difficile toxins. J Vet Intern Med. 1:158-163, 2017
Arroyo LG, Gomez DE, Martins C.Equine duodenitis-proximal jejunitis: A review. Can Vet J. 59:510-517, 2018