Spontaneous external biliary fistula in a dog.
METHODS
A 10-year-old sexually intact female dog was examined because of a static, well-circumscribed subcutaneous mass and associated fistulous draining tract located along the right ventrolateral aspect of the thoracic body wall of 15 months' duration.


RESULTS
Results of computed tomography and fistulography confirmed the presence of the fistulous tract. Computed tomography also revealed a focal, hypodense region in the right ventral portion of the liver that was adjacent to but not clearly associated with the fistulous tract.


RESULTS
Surgical exploration of the tract revealed that it passed into the right hemithorax to the diaphragm; entered the right medial lobe of the liver; and terminated in a well-encapsulated, cystic liver lesion. The right medial liver lobe and all affected tissues were removed. Histologically, the liver lesion consisted of a fibrotic, dilated bile duct. The dilated bile duct and fistula were lined with biliary epithelium. On the basis of these findings, a diagnosis of spontaneous external biliary fistula was made. Five months after surgery, the dog was clinically normal.


CONCLUSIONS
To the authors' knowledge, spontaneous external biliary fistula in a dog has not been reported in the veterinary medical literature. Despite the rarity of this condition, it should be considered in a dog with similar clinical findings. Clinical findings and results of appropriate diagnostic imaging procedures may provide valuable information in making this diagnosis and in planning surgical treatment.
Kligman
Kara C
KC
Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL 32610-0126, USA.
Jehn
Carl T
CT
Davis
Kechia M
KM
Taylor
David P
DP
Conway
Julia A
JA
D000818:Animals; D001658:Biliary Fistula / Q000175:diagnosis / Q000601:surgery / Q000662:veterinary*; D003937:Diagnosis, Differential; D004283:Dog Diseases / Q000175:diagnosis* / Q000601:surgery; D004285:Dogs; D005260:Female; D014057:Tomography, X-Ray Computed / Q000662:veterinary; D016896:Treatment Outcome