Esophageal cyst in the duodenum of a foal.

The study describes a case where a three-week-old Thoroughbred colt was put down due to repeated colic episodes. An autopsy revealed an occlusive, submucosal cyst in the duodenum, and was diagnosed as an esophageal cyst based on the pathological and gross examination.

The Medical Condition

• Colic refers to severe abdominal discomfort in horses. It’s a common ailment which can be caused by different conditions varying in terms of severity.
• In the case discussed, it is the result of an esophageal cyst. Esophageal cysts are rare and usually benign, but their presence can lead to complications, such as causing obstructions, like in this study.

Pathological Process

• The colt was euthanized due to a history of recurrent colic episodes, indicating the animal was suffering from persistent and potentially severe discomfort.
• An autopsy carried out on the animal led to the discovery of an occlusive, submucosal cyst in the duodenum, which would have likely contributed to the recurrent colic.
• An occlusive cyst creates a blockage within the organ they are located in. In this context, the cyst was present in the duodenum (part of the small intestine) which will have caused complications in digesting food and caused distress to the animal.

Diagnosis

• The cyst was diagnosed as an esophageal cyst based on the physical and pathological features. This kind of cyst is extremely unusual, particularly within the duodenum.
• The cyst measured 4.5 cm in diameter, quite a large size considering the age and size of a newborn foal. The cyst’s size would have significantly obstructed the duodenum, invariably leading to digestive disturbance.
• Upon pathological evaluation, the cyst was seen to be surrounded by a smooth muscle wall and was lined by both squamous (flat, scale-like) and attenuated (narrowed) cuboidal to columnar epithelium (cells that line the surfaces and cavities of the body’s tissues).
• This combination of features allowed for the diagnosis of the cyst as an esophageal cyst, a significant finding because such cysts are rarely seen in horses, let alone foals.