Serum hyaluronic acid, a marker for improved liver perfusion after gradual surgical attenuation of extrahepatic portosystemic shunt closure in dogs

Congenital Portosystemic Shunts in Dogs and Cats: Treatment, Complications and Prognosis

Congenital portosystemic shunts (CPSS) are a common vascular anomaly of the liver in dogs and cats. Clinical signs of CPSS are non-specific and may wax and wane, while laboratory findings can raise the clinical suspicion for CPSS, but they are also not specific. Definitive diagnosis will be established by evaluation of liver function tests and diagnostic imaging. The aim of this article is to review the management, both medical and surgical, complications, and prognosis of CPSS in dogs and cats. Attenuation of the CPSS is the treatment of choice and may be performed by open surgical intervention using ameroid ring constrictors, thin film banding, and partial or complete suture ligation or by percutaneous transvenous coil embolization. There is no strong evidence to recommend one surgical technique over another. Medical treatment strategies include administration of non-absorbable disaccharides (i.e., lactulose), antibiotics, and dietary changes, and are indicated for pre-surgical stabilization or when surgical intervention is not feasible. After CPSS attenuation, short- and long-term post-surgical complications may be seen, such as post-operative seizures and recurrence of clinical signs, respectively. Prognosis after surgical attenuation of CPSS is generally favorable for dogs and fair for cats.

Laparoscopic attenuation of a congenital extrahepatic portosystemic shunt in a dog—a thin-film banding for splenophrenic shunt: A case report

A 6-year-old castrated male Shih-Tzu dog weighing 6. 5 kg presented with chief complaints of pollakiuria and urine dribbling. He had a history of urolithiasis for 3 years, which was confirmed by the presence of ammonium urate in the urinary stone analysis, performed 2 years prior to the presentation. Blood examination showed high values of fasting ammonia, post-prandial bile acid, and low blood urea nitrogen. Microhepatica and urolithiasis were identified on plain radiography and ultrasonography. A computed tomography angiography demonstrated a shunting vessel, diameter up to 9.6 mm, originated from the splenic vein, and linked with the phrenic vein. A surgical attenuation with a thin-film banding was performed under laparoscopic visualization. Left triangular ligament was incised, and one stay suture was placed to the stomach to expose the vessel. The shunting vessel was dissected before it entered the diaphragm, and a thin-film band was applied around the vessel. The patient recovered uneventfully without post-attenuation neurologic signs. Portal vein diameter increased with time, and complete closure of the shunting vessel was identified on computed tomography angiography performed at 14 months after attenuation. The patient was doing well for 31 months after surgery without protein restriction. This is a report of laparoscopic attenuation for splenophrenic type of canine congenital extrahepatic portosystemic shunt with a favorable outcome using thin-film banding.

The microvascular endothelial glycocalyx: An additional piece of the puzzle in veterinary medicine

The endothelial glycocalyx (eGlx) is a critically important structure lining the luminal surface of endothelial cells. There is increasing evidence, in human patients and animal models, for its crucial role in the maintenance of health. Moreover, its damage is associated with the pathogenesis of multiple disease states. This review provides readers with an overview of the eGlx; summarising its structure, essential functions, and evidence for its role in disease. We highlight the lack of studies regarding the eGlx in cats and dogs, particularly in naturally occurring diseases. Importantly, we discuss techniques to aid its study, which can be applied to veterinary species. Finally, we present targeted therapies aimed at preserving, and in some cases, restoring damaged eGlx.

Evaluation of different blood tests in dogs with extrahepatic portosystemic shunts to assess shunt closure after surgical treatment

OBJECTIVE

To determine the sensitivity and specificity of different individual and combined blood tests to assess extrahepatic portosystemic shunt (EHPSS) closure after gradual attenuation of EHPSS in dogs.

STUDY DESIGN

Clinical prospective study.

ANIMALS

Twenty client-owned dogs with EHPSS.

METHODS

Fasting ammonia (FA), preprandial, postprandial, and paired serum bile acids (SBA), the lidocaine/monoethylglycylxylidide (L/MEGX) test, and serum hyaluronic acid (SHA) were performed at diagnosis, and 1, 3, and 6 months postoperatively. Transsplenic portal scintigraphy was performed to determine EHPSS closure 3 months postoperatively. Their sensitivity and specificity in determining shunt closure postoperatively were calculated.

RESULTS

When assessing a single blood parameter, FA had the highest specificity (100%), whereas SHA and MEGX measured 15 min after lidocaine administration (T15) had the highest sensitivity (96.9% and 96.2%, respectively) for determining shunt closure postoperatively. The most promising blood test combinations were SHA (sensitivity 96.9%, specificity 81.8%), combined with the L/MEGX test (MEGX at T15: sensitivity 100%, specificity 72.4%) or the L/MEGX test (MEGX at T15) combined with either FA (sensitivity 100%, specificity 82.8%) or postprandial SBA (sensitivity 100%, specificity 81.5%).

CONCLUSION

Both SHA and the L/MEGX test were sensitive tests for determining shunt closure after gradual attenuation of EHPSS. Test performances could even be improved by combining these tests with each other or with traditional tests such as FA or postprandial SBA.

CLINICAL SIGNIFICANCE

Although SHA and the L/MEGX test are sensitive blood tests for determining EHPSS closure, especially when combined with traditional blood tests, imaging is still needed to confirm EHPSS closure.