Case Of the Month

Portosystemic Splenocaval Shunt In A 4-Year-Old MN Maltese. Our Case Study Of The Month August 2014

A 4-year-old MN Maltese was presented for an annual exam, but the dog had been noted to be losing weight. Physical exam was unremarkable. Blood chemistry revealed hyperphosphatemia, and elevated ALT, and AST enzyme activities . CBC found leukocytosis consisting of a neutrophilia, lymphocytosis, and monocytosis. The patient was nonresponsive to antibiotic therapy over a 3 week period. The patient was doing well on re-evaluation; he had a good appetite, but was still losing weight. Recheck blood chemistry still showed persistently elevated liver enzyme activities, hypocholesterolemia, low urea and creatinine concentrations. The neutrophilia and monocytosis were still present on the CBC, however thrombocytopenia was also present. Serum bile acids were severely elevated, both pre and post-prandial. A coagulation panel was within normal limits.

DX

Portosystemic shunt splenocaval shunt

Outcome

The patient responded well to surgical intervention and post op management with L/D diet and lactulose therapy. Bile acids remained elevated at pre 30/post83 umol/L at a 5 month follow-up. The follow up ultrasound was unremarkable with no bladder calculi formation and the patient was clinically stable.

Comments

Image set performed by Dr. Eric Lindquist.

Clinical Differential Diagnosis

Cholangitis, hepatitis or cholangiohepatitis with a possible mucocele , previously undiagnosed portosytemic shunt causing decreased cholesterol and urea production. A low creatinine concentration may be due to poor body condition, neoplasia of the liver (primary vs. metastatic; hepatocellular adenoma, lymphoma, adenocarcinoma, leiomyoma, leiomyosarcoma, mast cell tumor, histiocytic sarcoma, etc.) pancreatic neoplasia (adenocarcinoma,) intestinal neoplasia (lymphoma, adenocarcinoma, leiomyoma, leiomyosarcoma, mast cell tumor, histiocytic sarcoma, etc.)

Sampling

The patient was referred to a board certified surgeon and an exploratory laparotomy was performed. A PSS was confirmed at surgery and ameroid constrictor placed. The liver biopsy performed showed concurrent microvascular dysplasia.

Sonographic Differential Diagnosis

Portacaval (splenocaval) shunt extra hepatic. Concurrent urinary bladder calculi.

Image Interpretation

The urinary bladder, presented approximately 3-6 shadowing small calculi measuring approximately 0.3cm each. The bladder wall was structurally normal. The liver presented mild subnormal size. The parenchyma was uniform with no significant evidence of structural disease, however the liver presented mildly poor vascularity. The gallbladder was mildly prominent. The portal vein at the portal hilus measured 0.45cm. However a 0.6cm portocaval (splenocaval) shunt cranial to the right kidney was present. The portal vein prior to the shunt deviation was 0.7cm. The shunt itself was 0.65cm and appeared to be portocaval in nature given that the vena cava at the portal hilus measured approximately 1.1cm with the aorta at 0.7cm. There appeared to be a possible second connection in an intrahepatic position between the right branch of the portal vein and the caudal vena cava, however this could not be overtly confirmed by ultrasound and this should be investigated at the time of surgery.