Clinical Features of Phrenic Vessel-Related Congenital Extrahepatic Portosystemic Shunts in Five Dogs
Phrenic vessel-related portosystemic shunt (Pr-PSS) is one of the major types in congenital extrahepatic portosystemic shunts (cEHPSS) in dogs. Its morphological characteristics have been well described in several studies. However, there are only few articles on clinical features of Pr-PSS in dogs.
To describe clinical features of Pr-PSS in 5 dogs and compare the characteristics with gastrocaval and splenocaval types of cEHPSS patients in the same institution from August 2015 to February 2018.
Medical and surgical records were retrospectively analyzed for clinical presentation, history, physical examination findings, clinicopathologic data, diagnostic imaging findings, medical and surgical treatment, surgical complications, and outcome.
All five patients were non-Maltese breed dogs, while 9/10 (90%) of dogs of portocaval and gastrocaval cEHPSS were Maltese. Two patients who were diagnosed less than one-year-old had congenital abnormalities including hydrocephalus, patent ductus arteriosus, cryptorchism, ureterocele, and ectopic ureter. Two patients showed no evidence related to cEHPSS while three patients presented with neurological signs including abnormal blood examination results. Older patients had age-related diseases such as cardiac disorders or liver mass. There was a major iatrogenic hemorrhage of a shunt vessel in a surgical procedure. In this case, the shunt had to be ligated completely to control the bleeding. The patient had no signs of portal hypertension and all patients recovered well.
It is beneficial to perform computed tomography for non-Maltese small-breed dogs with other congenital abnormalities to rule out or diagnose Pr-PSS due to the subclinical characteristics, diagnostic challenge with abdominal ultrasonography, and high prevalence.