Proximal Enteritis Case

We were called out to a farm yesterday to see a 10 year old Standardbred gelding “Andy” who had a fever of 103 deg. F, dark urine, and depression. When we got there, he was a little sweaty and looked like he had been rolling. On physical exam, his heart rate and respiratory rate were elevated (52 beats/min and 36 breaths/min). He was approximately 5-7% dehydrated. On rectal palpation, he had scant manure and mucus, and his cecum was moderately distended. When we passed a nasogastric tube, we obtained over a gallon of yellow, foul smelling bile from his stomach. With banamine, sedation, and several liters of IV fluids, the gelding’s heart rate, respiratory rate, and temperature decreased. His attitude also improved and he drank some water. However, he continued to spontaneously reflux out of the nasogastric tube intermittently.

The veterinarian presumptively diagnosed proximal enteritis (aka anterior enteritis or duodenitis -proximal jejunitis). This is a type of colic caused by a functional obstruction. Inflammation of the duodenum and proximal part of the jejunum lead to ileus – cessation of small intestinal motility. The stomach and small intestine hypersecrete fluid which has nowhere to go and can eventually rupture the stomach if a nasogastric tube is not placed. The horse can become hypovolemic due to loss of fluid into the GI tract. The cause is thought to be bacterial, either Clostridium difficile or C. perfringens or Salmonella spp, but is not well understood. There is a significant risk of endotoxemia or endotoxic shock occurring due to leakage of bacteria from the gut.

In this case, we suspect the proximal enteritis was initiated by a change in diet. The owners were running low on hay so they switched to a diet of primarily grain and a few hours turnout on pasture. After initial treatment, we referred this horse to a specialty hospital for in-patient care. He will need large amounts of IV fluids for the next few days, gastric decompression through the NG tube every two hours, IV antibiotics and pain medications, and his feet iced to prevent laminitis. We anticipate that “Andy” will have a good prognosis, since despite the severity of his condition it seems that it was caught early and the owners were able to take him promptly to a referral facility. His owners, an Amish couple, use him for driving and he is their only horse, so we wish him a full and speedy recovery!