title: Diagnosis of congenital portosystemic shunt in miniature schnauzers 7 years of age or older (1997-2006).
abstract: Dogs with congenital portosystemic shunt (PSS) are typically diagnosed before 2 years of age. The objective of this study was to determine if miniature schnauzers are more likely to be diagnosed with congenital PSS at an older age than are other breeds. This retrospective study examined the case records of 171 dogs diagnosed with congenital PSS; dogs were included if they were definitively diagnosed as having congenital PSS by nuclear scintigraphy, contrast portography, and/or exploratory surgery. Seven (23%) of 31 miniature schnauzers diagnosed with congenital PSS were 7 years of age or older at the time of diagnosis, compared to 3.4% for all other breeds. Miniature schnauzers had a relative prevalence ratio of 6.3 (95% confidence interval 2.2 to 18.6; P=0.001) for being diagnosed at or after 7 years of age when compared to all other breeds of dogs. Clinical signs of congenital PSS may not manifest sufficiently to cause an owner to seek veterinary care for some dogs until they are older. Congenital PSS should be considered in mature dogs, particularly miniature schnauzers, that are presented with signs potentially consistent with hepatic encephalopathy.
authors.affiliation: Departments of Small Animal Clinical Sciences, College of Veterinary Medicine, Texas A&M University, College Station, Texas 77843, USA.
authors.forename: Michelle
authors.initials: M
authors.lastname: Mertens
authors.forename: Theresa W
authors.initials: TW
authors.lastname: Fossum
authors.forename: Michael D
authors.initials: MD
authors.lastname: Willard
authors.forename: Geoffrey T
authors.initials: GT
authors.lastname: Fosgate
authors.forename: Angel Garcia
authors.initials: AG
authors.lastname: de la Paz
authors.forename: Ryan
authors.initials: R
authors.lastname: Farmer
authors.forename: Matthew W
authors.initials: MW
authors.lastname: Miller
mesh_terms: D000367:Age Factors; D000818:Animals; D004283:Dog Diseases / Q000151:congenital* / Q000175:diagnosis; D004285:Dogs; D005260:Female; D020022:Genetic Predisposition to Disease; D008297:Male; D010375:Pedigree; D011168:Portal System / Q000002:abnormalities*; D012189:Retrospective Studies