## Overview Anterior enteritis, also called duodenitis-proximal jejunitis, is an inflammatory condition of the duodenum and proximal jejunum that produces functional ileus and massive fluid secretion into the small intestine. Large volumes of gastric reflux result, leading to dehydration, electrolyte imbalances, and endotoxemia. The disease is sporadic and appears more severe in the southeastern United States. Approximately 30 percent of cases develop laminitis as a complication. ## Causes The etiology remains unknown. Clostridium species and Salmonella have been isolated from reflux in some cases, but consistent causation has not been proven. Dietary factors, particularly high-concentrate feeding or abrupt diet changes, are suspected contributors in some horses. ## Diagnosis Acute onset of moderate to severe colic, fever, depression, and large volumes of orange-brown nasogastric reflux are characteristic. Rectal examination reveals distended small intestine. Differentiation from mechanical small-intestinal obstruction is critical; horses with anterior enteritis often become more comfortable after gastric decompression and may be febrile early, whereas obstructive cases usually worsen. ## Treatment Repeated nasogastric decompression, aggressive intravenous fluid therapy, anti-endotoxic and anti-inflammatory medication, and prokinetic agents form the mainstay of therapy. Broad-spectrum antibiotics are frequently administered. Surgery is reserved for cases that cannot be distinguished from strangulating obstruction or that fail to improve. ## Recovery and Prognosis Prognosis is guarded and depends largely on the duration of reflux and the development of laminitis or other complications. Horses whose reflux resolves within 48 to 72 hours generally have a better outlook. Laminitis markedly worsens prognosis. ## Prevention No specific prevention is established. Gradual dietary changes and avoidance of abrupt increases in concentrate may reduce risk in susceptible individuals.
acute colic; fever; depression; large volumes of nasogastric reflux; distended small intestine on rectal examination; tachycardia
## Overview Anterior enteritis, also called duodenitis-proximal jejunitis, is an inflammatory condition of the duodenum and proximal jejunum that produces functional ileus and massive fluid secretion into the small intestine. Large volumes of gastric reflux result, leading to dehydration, electrolyte imbalances, and endotoxemia. The disease is sporadic and appears more severe in the southeastern United States. Approximately 30 percent of cases develop laminitis as a complication. ## Causes The etiology remains unknown. Clostridium species and Salmonella have been isolated from reflux in some cases, but consistent causation has not been proven. Dietary factors, particularly high-concentrate feeding or abrupt diet changes, are suspected contributors in some horses. ## Diagnosis Acute onset of moderate to severe colic, fever, depression, and large volumes of orange-brown nasogastric reflux are characteristic. Rectal examination reveals distended small intestine. Differentiation from mechanical small-intestinal obstruction is critical; horses with anterior enteritis often become more comfortable after gastric decompression and may be febrile early, whereas obstructive cases usually worsen. ## Treatment Repeated nasogastric decompression, aggressive intravenous fluid therapy, anti-endotoxic and anti-inflammatory medication, and prokinetic agents form the mainstay of therapy. Broad-spectrum antibiotics are frequently administered. Surgery is reserved for cases that cannot be distinguished from strangulating obstruction or that fail to improve. ## Recovery and Prognosis Prognosis is guarded and depends largely on the duration of reflux and the development of laminitis or other complications. Horses whose reflux resolves within 48 to 72 hours generally have a better outlook. Laminitis markedly worsens prognosis. ## Prevention No specific prevention is established. Gradual dietary changes and avoidance of abrupt increases in concentrate may reduce risk in susceptible individuals.
acute colic; fever; depression; large volumes of nasogastric reflux; distended small intestine on rectal examination; tachycardia