Clinical outcomes for 20 cats with congenital extrahepatic portosystemic shunts treated with ameroid constrictor ring attenuation (2002-2020).

OBJECTIVE: To report the clinical perioperative, short-term, and long-term outcomes for cats undergoing ameroid ring constrictor (ARC) attenuation of a congenital extrahepatic portosystemic shunt (EHPSS). STUDY DESIGN: Retrospective case series from a single veterinary teaching hospital (2002-2020). ANIMALS: Twenty client-owned cats with EHPSS. METHODS: Data collected from medical records included signalment, history, physical examination, clinicopathologic testing, medications, diagnostic imaging, intraoperative findings, perioperative complications, and postoperative clinical outcomes. Long-term clinical outcome was obtained from a standardized owner interview or medical records. RESULTS: Perioperative complications were reported in five cats out of 20, including blindness (two cats), ascites (one cat), head pressing (one cat), and seizures and death (one cat). Short-term clinical outcome was excellent in 14/18 cats, good in 2/18 cats, and poor in 2/18 cats that were available for follow up, and long term clinical outcome was excellent in 15/18, good in 1/18 cats, and poor in 2/18 cats that were available for follow up. CONCLUSION: Long-term clinical outcome was good or excellent in 16/18 of cats available for follow up. Perioperative complications were reported in five cats. CLINICAL SIGNIFICANCE: Surgical attenuation of EHPSS with an ARC can result in resolution of clinical signs and biochemical abnormalities in the majority of cats. The perioperative complication rate for feline patients with EHPSS attenuated with an ARC was lower than reported historically. Seizures may persist in the long term despite normal bile acid stimulation test results, complete blood count, and biochemistry analysis.

Repeated specific canine pancreatic lipase measurements do not identify multiple acquired portosystemic shunts in dogs after extrahepatic portosystemic shunt attenuation.

BACKGROUND: In dogs with portal hypertension (PH), spec cPL is suggested to be increased despite normal pancreatic histology. After attenuation of congenital extrahepatic portosystemic shunts (cEHPSS), multiple acquired portosystemic shunt (MAPSS) can develop as consequence of sustained PH. Presence of MAPSS affects future therapeutic options and prognosis. OBJECTIVE: Evaluate if spec cPL concentrations increase postoperatively in dogs that develop MAPSS and can thus serve as an indicator of PH. ANIMALS: Twenty-four dogs with cEHPSS. METHODS: Dogs classified according to surgical outcome after cEHPSS attenuation (8 with MAPSS [group M], 9 with closed cEHPSS [group C] and 7 with patent blood flow through the original cEHPSS, without evidence of MAPSS [group P]). Spec cPL was measured in preoperative samples (T0), 4 days (T1) and 1 (T2) and 3- to 6-months (T3) after surgery. RESULTS: Spec cPL was within reference interval (<200 µg/L) at all timepoints except at T1. At T1, 2 dogs in group M (321 and >2000 µg/L) and also 1 in group C (688 µg/L) and 1 in group P (839 µg/L) had increased spec cPL concentrations. No differences in spec cPL concentrations between groups or changes over time were identified. CONCLUSIONS AND CLINICAL IMPORTANCE: Spec cPL is not consistently increased in dogs that develop MAPSS after cEHPSS attenuation and has no potential as a biomarker for the identification of MAPSS after cEHPSS attenuation.

Jejunal arteriovenous malformation and multiple acquired extrahepatic portosystemic shunts in a juvenile dog, presenting with melena.

A juvenile dog referred with a 1-month history of persistent melena and severe anaemia, was diagnosed with a jejunal arteriovenous malformation, and multiple acquired extrahepatic portosystemic shunts. A midline coeliotomy was performed, the jejunal arteriovenous malformation was localised intraoperatively and was successfully removed via an enterectomy. Histopathology confirmed a true arteriovenous malformation. Despite the initial improvement, the patient developed seizure episodes secondary to hepatic encephalopathy 8 months after surgery. Fifteen months after surgery, the owner opted for euthanasia due to the ongoing seizure episodes. Post-mortem histologic examination of the liver showed features consistent with portal vein hypoplasia. A congenital arteriovenous malformation should be considered as a differential diagnosis in juvenile patients with a chronic history of haemorrhage from the gastrointestinal tract. In addition, acquired portosystemic shunts may occur in patients with portal vein hypoplasia and jejunal arteriovenous malformations.

Prediction of outcome after ligation or thin film banding of extrahepatic shunts, based on plasma albumin concentration and hematologic expression of 8 target genes in 85 dogs.

BACKGROUND: In dogs with a congenital extrahepatic portosystemic shunt (EHPSS), outcome after surgical attenuation is difficult to predict. OBJECTIVES: Develop a minimally invasive test to predict outcome after surgical EHPSS attenuation and establish risk factors for postattenuation seizures (PAS). ANIMALS: Eighty-five client-owned dogs referred for surgical attenuation of a single EHPSS. METHODS: mRNA expression of 8 genes was measured in preoperatively collected venous blood samples. Outcome was determined at a median of 92 days (range, 26-208) postoperatively by evaluating clinical performance, blood test results and abdominal ultrasonography. Multivariable logistic regression was used to construct models predicting clinical and complete recovery. The associations between putative predictors and PAS were studied using univariable analyses. RESULTS: Five of 85 dogs developed PAS. Risk factors were age, white blood cell (WBC) count and expression of hepatocyte growth factor activator and LysM and putative peptidoglycan-binding domain-containing protein 2. Clinical recovery was observed in 72 of 85 dogs and complete recovery in 51 of 80 dogs (median follow-up, 92 days). The model predicting clinical recovery included albumin, WBC count, and methionine adenosyltransferase 2 alpha (MAT2α) expression, whereas the model predicting complete recovery included albumin, and connective tissue growth factor precursor and MAT2α expression. The areas under the receiver operating characteristic curves were 0.886 (95% confidence interval [CI]: 0.783, 0.990) and 0.794 (95% CI: 0.686, 0.902), respectively. CONCLUSIONS AND CLINICAL IMPORTANCE: Two models were constructed for predicting outcome after EHPSS attenuation using venous blood samples. The model predicting clinical recovery showed the best diagnostic properties. Clinical application requires further validation.

Postattenuation neurologic signs after surgical correction of congenital portosystemic shunts in cats: A narrative review.

Development of postattenuation neurological signs (PANS) is a potentially severe complication after surgical attenuation of congenital portosystemic shunts in cats. This review summarizes findings of 15 publications that report occurrence of PANS in cats. PANS includes seizures but also milder neurologic signs such as blindness, ataxia, abnormal behavior, tremors, and twitching. Incidence of PANS and specifically postattenuation seizures in studies including a minimum of five cats ranges from 14.3% to 62.0% and 0% to 32.0%, respectively. Etiology of PANS in cats is unknown, however, several hypotheses have been proposed including central nervous system disease/derangement, perioperative hypoglycemia and electrolyte disturbances, and postoperative portal hypertension. A number of possible risk factors have been identified including lower grades of intraoperative postocclusion mesenteric portovenography and osmolality at 24 h postoperatively. Evidence for use of prophylactic antiepileptics such as levetiracetam to prevent or reduce incidence of PANS in cats is limited and does not support their use. Because the cause is unknown, treatment is aimed at controlling neurologic signs, preventing progression to more severe signs, and providing general supportive care. Prospective studies comparing the efficacy of different antiepileptics for treatment of PANS in cats are required. Prognosis for recovery is variable and dependent on severity of neurologic signs. For cats surviving to discharge, long-term survival is possible but persistence or recurrence of neurologic signs in the long-term is not uncommon.

Short- and long-term outcomes of polyethylene band attenuation of congenital extrahepatic portosystemic shunts in dogs: 60 cases (2010-2020).

OBJECTIVES: To report the short- and long-term outcomes following attenuation of congenital extrahepatic portosystemic shunts in dogs using a novel polyethylene band. MATERIALS AND METHODS: Records were retrospectively reviewed for dogs that underwent congenital extrahepatic portosystemic shunt attenuation by a polyethylene banding technique, at a single institution between 2010 and 2020. Short-term outcome data were collected from peri-operative clinical records with follow-up examinations, scheduled at 6 and 18 weeks post-operatively, and post-operative imaging when performed. Long-term follow-up was collected by validated owner questionnaire, telephone interview or medical records. Long-term outcomes were categorised by "excellent", "good" or "poor". RESULTS: Sixty dogs were included. Post-operative complications occurred in 10 of 60 dogs (16.7%), four major and six minor, with a peri-operative mortality of 6.7%. Persistent shunting was identified in nine of 53 dogs (17%) available for follow-up examination and four dogs underwent a revision surgery. Long-term follow-up was available for 44 dogs at a median of 75 months post-operatively (range 7 to 128). Long-term outcomes were "excellent" (26) or "good" (8) in 81.8% of dogs and "poor" (8) in 18.2%. At the time of follow-up, 30 of 44 (68.2%) dogs were not receiving any medical treatment and 27 of 28 (96.4%) questionnaire respondents were satisfied with the response to surgery. CLINICAL SIGNIFICANCE: Polyethylene band attenuation of congenital extrahepatic portosystemic shunts provides comparable outcomes to cellophane. The material used in this study is widely available and consistent while being pre-sterilised and pre-folded makes it easy to use.

Comparison of diet, lactulose, and metronidazole combinations in the control of pre-surgical clinical signs in dogs with congenital extrahepatic portosystemic shunts.

BACKGROUND: Hepatic supportive diet (HSD), lactulose, and antimicrobials are medical treatments for dogs with congenital extrahepatic portosystemic shunts (cEHPSS). The relative contribution of these treatment components is currently unknown. OBJECTIVES: To determine which treatment combinations are most efficacious in pre-surgical control of clinical signs of cEHPSS in dogs. ANIMALS: Thirty-six dogs with untreated cEHPSS. METHODS: Three-arm randomized clinical trial. At inclusion (T0), dogs were divided into 3 groups: HSD (n = 12), HSD + lactulose (n = 12), or HSD + metronidazole (n = 12) and received the randomized treatment for 4 weeks (T1) followed by combined treatment of HSD + lactulose + metronidazole for 2 weeks or until cEHPSS attenuation (T2). Clinical score as well as fasting ammonia (FA) and C-reactive protein (CRP) concentrations were compared among groups and time points. RESULTS: Thirty-four dogs were evaluated. Thirty-four dogs reached T1 and 29 dogs T2. At T1, clinical scores decreased in the HSD + lactulose (n = 11; P = .001), but not in the HSD (n = 8; P = .96) and HSD + metronidazole (n = 10; P = .06) groups. Adding metronidazole to HSD + lactulose (n = 11) did not result in further clinical score improvement (T2; P = 1.000). Moderate and weak correlation between clinical score and FA and clinical score and CRP was present (ρ = .35, P < .001; ρ = .27, P = .01, respectively) with FA decreasing over time on medical treatment (P = .001). CONCLUSIONS AND CLINICAL IMPORTANCE: Combined HSD + lactulose seems sufficient for pre-surgical cEHPSS stabilization unlike sole HSD or HSD + metronidazole. Medical treatment of cEHPSS clinical signs decreases FA.

Laparoscopic portosystemic shunt attenuation in 20 dogs (2018-2021).

OBJECTIVE: To describe the technique, complications, and outcome of laparoscopic portosystemic shunt attenuation (LPSSA) in dogs. STUDY DESIGN: Retrospective study. ANIMALS: Twenty client-owned dogs. METHODS: Medical records were searched for dogs with a single congenital extrahepatic portosystemic shunt (CEPSS) that was treated with LPSSA. Signalment, clinical signs, CEPSS location, diagnostic imaging, laparoscopic approach, operative technique, complications, and clinical outcome were reviewed. RESULTS: Fourteen dogs with CEPSS located in the epiploic foramen had a right (13/14) or left (1/14) paramedian approach. In 6 dogs a CEPSS was not located in the epiploic foramen, and a left paramedian approach was used. A 3 or 4-port technique was used in 7 and 13 dogs, respectively. A thin film band was used for CEPSS attenuation in all dogs. The median operating time for LPSSA was 62 min (range 27-98 min). Intraoperative complications requiring conversion to an open technique occurred in 5 dogs. Mild perioperative self-limiting portal hypertension occurred in 3 dogs, while severe portal hypertension with surgical revision occurred in 1 case. The complications were resolved, and all dogs had a good outcome. CONCLUSION: Laparoscopic portosystemic shunt attenuation can be performed in dogs, in particular for a CEPSS located in the epiploic foramen using a right paramedian approach. For CEPSS not located in the epiploic foramen, a left paramedian approach is recommended. Conversion to open celiotomy was required in around a third of cases. CLINICAL SIGNIFICANCE: Laparoscopic attenuation of CEPSSs can be performed in dogs and has a good clinical outcome, particularly for CEPSS located in the epiploic foramen.

Successful ligation of the left and right gastric vein in a dog with congenital portosystemic shunts type Aii.

The type Aii shunt is a congenital extrahepatic portosystemic shunt (ePSS) involving the left and right gastric vein and the caudal vena cava (CVC). This report describes the case of a 6-month-old Italian greyhound diagnosed with a type Aii large-diameter ePSS. Staged surgeries were employed to completely ligate the 2 gastric veins and to avoid the risk of traumatizing the shunt vessel, CVC, and celiac artery. Clinical signs improved postoperatively, and after 3 years, ultrasonography demonstrated no evidence of reoccurrence. This procedure provides an alternative surgical option for correction of ePSS type Aii. Key clinical message: This case report demonstrates congenital PSS involving the left and right gastric vein and the caudal vena could be treated with both ligation of left and right gastric vein. This technique could decrease the risk of traumatizing the shunt vessel, CVC, and celiac artery.

Ligature réussie des veines gastriques gauche et droite chez un chien avec des shunts portosystémiques congénitaux de type Aii. Le shunt de type Aii est un shunt porto-systémique extrahépatique congénital (ePSS) impliquant la veine gastrique gauche et droite et la veine cave caudale (CVC). Ce rapport décrit le cas d'un lévrier italien de 6 mois diagnostiqué avec un ePSS de grand diamètre de type Aii. Des chirurgies par étapes ont été effectuées pour ligaturer complètement les deux veines gastriques et pour éviter le risque de traumatiser le vaisseau avec shunt, la CVC et l'artère coeliaque. Les signes cliniques se sont améliorés après l'opération et après trois ans, l'échographie n'a montré aucun signe de récidive. Cette procédure offre une option chirurgicale alternative pour la correction de l'ePSS de type Aii.Message clinique clé :Ce rapport de cas démontre un ePSS congénital impliquant la veine gastrique gauche et droite et la veine caudale pouvant être traité par la ligature de la veine gastrique gauche et droite. Cette technique pourrait diminuer le risque de traumatiser le vaisseau avec shunt, le CVC et l'artère coeliaque.(Traduit par Dr Serge Messier).

Computed tomographic features of portal vein thrombosis in two cats with splenosystemic shunts.

Two spayed female cats presented with hepatic encephalopathy due to hyperammonaemia. On abdominal ultrasound, concurrent portal vein thrombosis and splenosystemic shunts were suspected in both cats. Computed tomographic angiography clearly detected thrombi as non-contrast enhancing intraluminal structures in the main portal vein of both cats. Additionally, splenorenal shunts were revealed in both cats. Follow-up computed tomographic angiography for portal vein thrombosis was performed in both cats, only one of whom received anticoagulant therapy. In the untreated cat, portal vein thrombosis had progressed with the development of an aberrant tortuous vessel. In the cat treated with low-molecular-weight heparin, the thrombus progressively decreased in size and disappeared on follow-up diagnostic imaging. Computed tomographic angiography might be useful for the diagnosis and follow-up of portal vein thrombosis in cats.

Serum insulin-like growth factor-1 as a marker of improved liver function and surgical outcome in dogs with congenital extrahepatic portosystemic shunts.

Serum insulin-like growth factor-1 concentration (sIGF-1c) is reduced in various hepatopathies in humans and dogs. This work aimed to evaluate sIGF-1c in dogs before and after congenital extrahepatic portosystemic shunt (cEHPSS) attenuation, in relation to surgical outcome (closed vs. persistent shunting). Secondarily, it aimed to assess if sIGF-1c can discriminate between cEHPSS and portal vein hypoplasia (PVH) and finally compare sIGF-1c ratio (postoperative/preoperative sIGF-1c) to pre-prandial serum bile acids (preBA), post-prandial bile acids (postBA), bile acid stimulation test (BAST) and fasting ammonia (FA), regarding surgical outcome. Thirty-nine dogs were included: 15 with closed cEHPSS, 15 with persistent shunting and nine with PVH. Transplenic portal scintigraphy was used to classifiy surgical outcome. There was no significant difference in sIGF-1c between dogs with cEHPSS and those with PVH (P > 0.05). Postoperative sIGF-1c increased in all dogs (P < 0.001 and P = 0.023 for closed and persistent shunting, respectively) and the increase was more pronounced in closed cEHPSS than in persistent shunting (P = 0.006). Using an optimal sIGF-1c ratio cut-off of 2.23, the sensitivity was 93.3% and the specificity was 66.7% for differentiation between surgical outcomes. Serum pre-prandial bile acids, postBA BAST and FA had sensitivities of 80%, 86.7%, 86.7%, 60%; and specificities of 100%, 93.3%, 93.3%, 100%, respectively. There was a greater increase in sIGF-1c after shunt closure than during persistent shunting; nevertheless sIGF-1c ratio was inferior to advanced imaging to assess surgical outcome.

Incidence and risk factors for neurological signs after attenuation of a single congenital portosystemic shunt in 50 cats.

OBJECTIVE: To determine the incidence, outcome, and risk factors for postattenuation neurological signs (PANS) in cats treated for single congenital portosystemic shunts (CPSS). STUDY DESIGN: Retrospective cohort study. ANIMALS: Cats (n = 50) with a single CPSS. METHODS: Medical records of cats treated by surgical attenuation of a single CPSS between 2003 and 2017 were reviewed for signalment, surgical technique, preoperative management and postoperative clinical outcomes. Binary logistic regression was performed to investigate risk factors for occurrence of PANS and seizures. RESULTS: Congenital portosystemic shunts in 50 cats included 40 extrahepatic and 10 intrahepatic shunts. Postattenuation neurological signs were recorded in 31 (62%) cats and graded as 1 in 10 cats, 2 in nine cats, and 3 in 12 cats. Postattenuation neurological signs included seizures in 11 cats. Five of 31 cats with PANS did not survive to discharge. No association was detected between PANS or seizures and the type of CPSS (intrahepatic or extrahepatic), degree of attenuation, age, or the use of perioperative levetiracetam or hepatic encephalopathy immediately preoperatively. Osmolality at a median 24 hours postoperatively was lower in cats with PANS (P < .049, Wald 3.867, odds ratio [Exp(B)] 0.855, CI 0.732-0.999). CONCLUSION: Postattenuation neurological signs are common complications in cats treated for CPSS. Preoperative levetiracetam did not prevent the occurrence of PANS or seizures. The only risk factor for PANS detected was lower postoperative Osmolality in cats with PANS at 24 hours. CLINICAL SIGNIFICANCE: Postattenuation neurological signs including seizures occur frequently in cats undergoing surgical attenuation of a CPSS. Preoperative levetiracetam did not protect against the development of PANS.

Prognostic factors for short-term survival of dogs that experience postattenuation seizures after surgical correction of single congenital extrahepatic portosystemic shunts: 93 cases (2005-2018).

OBJECTIVE: To identify prognostic factors for short-term survival of dogs that experience seizures within 7 days after surgical correction of single congenital extrahepatic portosystemic shunts (cEHPSS). STUDY DESIGN: Multi-institutional retrospective study. SAMPLE POPULATION: Ninety-three client-owned dogs. METHODS: Medical records at 14 veterinary institutions were reviewed to identify dogs that underwent surgical attenuation of a single cEHPSS from January 1, 2005 through February 28, 2018 and experienced postattenuation seizures (PAS) within 7 days postoperatively. Logistic regression analysis was performed to identify factors associated with 1-month survival. Factors investigated included participating institution, signalment, shunt morphology, concurrent/historical conditions, presence of preoperative neurologic signs, presence of preoperative seizures, aspects of preoperative medical management, surgical details including method and degree of shunt attenuation, type of PAS (focal only or generalized ± focal), drugs administered as part of the treatment of PAS, and development of complications during treatment of PAS. RESULTS: Thirty (32.3%) dogs survived to 30 days. Seventy-six (81.7%) dogs experienced generalized PAS. Factors positively associated with short-term survival included having a history of preoperative seizures (P = .004) and development of focal PAS only (P = .0003). Most nonsurvivors were humanely euthanized because of uncontrolled or recurrent seizures. CONCLUSION: Dogs that experienced PAS that had a history of preoperative seizures and those that experienced focal PAS only had significantly improved short-term survival. CLINICAL SIGNIFICANCE: The results of this study provide information that will help in the counseling of owners who seek treatment for PAS after surgical correction of cEHPSS. © 2020 The American College of Veterinary Surgeons.

Acral congenital superficial dermal lymphatic malformations in two unrelated cats: clinicopathological, dermoscopic and ultrastructural findings.

BACKGROUND: Cutaneous vascular malformations (CVM) represent a spectrum of human diseases identified at birth or in paediatric patients and classified according to the type of vessel affected. Confusing classification in human medicine has led to misdiagnoses and frequent nomenclature revision. Cutaneous lymphatic malformations (CLM) are reported sporadically in humans. OBJECTIVE: To describe the clinicopathological findings of superficial dermal cutaneous lymphatic malformations (SDCLM) in two cats. ANIMALS: Two unrelated adult domestic short hair cats. METHODS: The two cats were evaluated clinically and with a dermoscope for recurrent swelling and presence of vesicles oozing serosanguineous fluid affecting the right and left hind foot, respectively, since birth. Skin biopsy specimens were collected for histopathological and immunohistochemical evaluation and electron microscopy. RESULTS: A CVM was suspected based on the age of onset, clinical signs, results of diagnostic imaging and histopathological findings. Dermoscopy was used to describe the alterations of the skin surface. The involvement of the lymphatic vessels was confirmed using immunohistochemical findings and electron microscopy. CONCLUSION AND CLINICAL IMPORTANCE: To the best of the authors' knowledge, this is the first description of the clinical, dermoscopic, histopathological and ultrastructural characteristics of SDCLM in cats resembling the human counterpart. SDCLMs are rare conditions and appropriate histopathological and immunohistochemical confirmation is required to avoid misdiagnosis and mistreatment.

The effect of neuraxial morphine on postoperative pain in dogs after extrahepatic portosystemic shunt attenuation.

OBJECTIVE: To investigate the analgesic effect of epidural morphine after surgical extrahepatic portosystemic shunt (EHPSS) attenuation. STUDY DESIGN: Randomized clinical trial. ANIMALS: A total of 20 dogs with a congenital EHPSS. METHODS: Dogs were randomly allocated to be given either a single epidural dose of 0.2 mg kg-1 preservative-free morphine (group M) or not (group C) before surgery. All dogs were administered 0.3 mg kg-1 methadone intravenously (IV) as preanaesthetic medication. Pain scores were determined every 2 hours for the first 24 hours postoperatively using the short-form Glasgow Composite Measure Pain Scale (GCMPS-SF). Dogs with a GCMPS-SF pain score >4/20 or >5/24 received 0.1 mg kg-1 methadone IV as rescue analgesia and were reassessed 30 minutes later. If more than three doses of methadone were administered in a 2 hour period, alternative pain relief was provided and a treatment failure recorded. The GCMPS-SF pain scores and number of rescue analgesia injections were analysed over 24 hours. The last observation carried forward method was applied in case of treatment failure. Food consumption and time to first urination were recorded. Data were analysed using a Mann-Whitney U test and presented as median (minimum-maximum range), with significance set at p < 0.05. RESULTS: Group M showed lower GCMPS-SF pain scores [15 (11-41) versus 31 (11-86); p = 0.023] and lower postoperative methadone requirements [0 (0-0.2) versus 0.25 (0-0.5) mg kg-1; p = 0.029] than group C. There were three treatment failures in group C only. Food consumption and time to first urination did not differ between groups. CONCLUSIONS AND CLINICAL RELEVANCE: Epidural morphine reduced the requirement for postoperative analgesia in this study population.

Efficacy of orally administered sodium benzoate and sodium phenylbutyrate in dogs with congenital portosystemic shunts.

BACKGROUND: Hyperammonemia can result in hepatic encephalopathy, which in severe cases eventually can lead to coma and death. In dogs, congenital portosystemic shunts (CPSS) are the most common cause for hyperammonemia. Conservative treatment consists of a protein modified diet, nonabsorbable disaccharides, antibiotics, or some combinations of these. Sodium benzoate (SB) and sodium phenylbutyrate (SPB) both are used in the acute and long-term treatment of humans with hyperammonemia caused by urea cycle enzyme deficiencies. Both treatments are believed to lower blood ammonia concentrations by promoting excretion of excess nitrogen via alternative pathways. OBJECTIVES: To evaluate the efficacy and safety of PO treatment with SB and SPB on hyperammonemia and clinical signs in CPSS dogs. METHODS: Randomized, double-blind, placebo-controlled crossover trial. Concentrations of blood ammonia and bile acids were measured in CPSS dogs before and after a 5-day treatment with SB, SPB, and placebo. A wash-out period of 3 days was used between treatments. A standard questionnaire was developed and distributed to owners to evaluate clinical signs before and after each treatment. RESULTS: Blood ammonia concentrations were not influenced by any of the treatments and were comparable to those observed during placebo treatment. In addition, SB and SPB treatment did not result in improvement of clinical signs. Adverse effects during treatment included anorexia, vomiting, and lethargy. CONCLUSIONS AND CLINICAL IMPORTANCE: Based on our results, we conclude that SB or SPB are not useful in the conservative treatment of hyperammonemia in dogs with CPSS.

Untargeted metabolomic profiling of serum from dogs with chronic hepatic disease.

BACKGROUND: Chronic hepatopathies present a diagnostic challenge, with different diseases being associated with similar clinical and laboratory findings. Characterization of dogs with chronic hepatopathies can be difficult and require costly diagnostic procedures such as acquisition of a liver biopsy specimen. Noninvasive and inexpensive biomarkers that reliably characterize chronic hepatopathies such as chronic hepatitis or a congenital portosystemic vascular anomaly may decrease the need for costly or invasive diagnostic testing and guide novel therapeutic interventions. OBJECTIVE: To investigate differences in the serum metabolome among healthy dogs, dogs with congenital portosystemic shunts, and dogs with chronic hepatitis. ANIMALS: Stored serum samples from 12 healthy dogs, 10 dogs with congenital portosystemic shunts, and 6 dogs with chronic hepatitis were analyzed. METHODS: The serum metabolome was analyzed with an untargeted metabolomics approach using gas chromatography-quadrupole time of flight mass spectrometry. RESULTS: Principal component analysis and heat dendrogram plots of the metabolomics data showed clustering among individuals in each group. Random forest analysis showed differences in the abundance of various metabolites including increased aromatic amino acids and xylitol in dogs with congenital portosystemic shunts. Based on the univariate statistics, 50 metabolites were significantly different among groups. CONCLUSIONS AND CLINICAL IMPORTANCE: The serum metabolome varies among healthy dogs, dogs with congenital portosystemic shunts, and dogs with chronic hepatitis. Statistical analysis identified several metabolites that differentiated healthy dogs from dogs with vascular or parenchymal liver disease. Further targeted assessment of these metabolites is needed to confirm their diagnostic reliability.

Effect of prophylactic treatment with levetiracetam on the incidence of postattenuation seizures in dogs undergoing surgical management of single congenital extrahepatic portosystemic shunts.

OBJECTIVE: To report the incidence of postattenuation seizures (PAS) in dogs that underwent single congenital extrahepatic portosystemic shunt (cEHPSS) attenuation and to compare incidence of PAS in dogs that either did or did not receive prophylactic treatment with levetiracetam (LEV). STUDY DESIGN: Multi-institutional retrospective study. POPULATION: Nine hundred forty dogs. METHODS: Medical records were reviewed to identify dogs that underwent surgical attenuation of a single cEHPSS from January 2005 through July 2017 and developed PAS within 7 days postoperatively. Dogs were divided into 3 groups: no LEV (LEV-); LEV at ≥15 mg/kg every 8 hours for ≥24 hours preoperatively or a 60 mg/kg intravenous loading dose perioperatively, followed by ≥15 mg/kg every 8 hours postoperatively (LEV1); and LEV at <15 mg/kg every 8 hours, for <24 hours preoperatively, or continued at <15 mg/kg every 8 hours postoperatively (LEV2). RESULTS: Seventy-five (8.0%) dogs developed PAS. Incidence of PAS was 35 of 523 (6.7%), 21 of 188 (11.2%), and 19 of 228 (8.3%) in groups LEV-, LEV1, and LEV2, respectively. This difference was not statistically significant (P = .14). No differences between groups of dogs that seized with respect to investigated variables were identified. CONCLUSION: The overall incidence of PAS was low (8%). Prophylactic treatment with LEV according to the protocols that were investigated in our study was not associated with a reduced incidence of PAS. CLINICAL SIGNIFICANCE: Prophylactic treatment with LEV does not afford protection against development of PAS. Surgically treated dogs should continue to be monitored closely during the first 7 days postoperatively for seizures.

Feasibility of complete surgical ligation on 72 dogs with singular extrahepatic congenital portosystemic shunt based on portal pressure and comparison of intraoperative mesenteric portovenography.

The relation between complete or partial ligation of extrahepatic portosystemic shunting and intraoperative mesenteric portovenography (IMP) was evaluated in 72 canines. Of the 72 dogs, 55 had complete ligation and 17 underwent partial ligation of abnormal vessels. IMP allowed evaluation of the number of intrahepatic portal branches and ratio of the diameter of cranial (CrPV) and caudal main portal vein (CaPV) at the shunt location. Nearly all cases in the complete ligation group and nearly half of the cases in the partial ligation group had three or more portal vein branches. CrPV/CaPV was 0.75 ± 0.24 in the complete ligation group and 0.29 ± 0.15 in the partial ligation group. CrPV/CaPV can be an effective new method for assessing IMP.

Spongiform encephalomyelopathy in a calf with a congenital portosystemic shunt.

A 3-month-old Holstein heifer calf was presented because of an abnormal gait. Further examination revealed cranial nerve deficits, including a severely delayed corneal reflex. The calf was not ataxic and maintained an appetite, but was considerably stunted for her age. A postmortem examination resulted in a diagnosis of a congenital portosystemic shunt.

Encéphalomyélopathie spongiforme chez un veau atteint d'un shunt portosystémique congénital. Une génisse Holstein âgée de 3 mois a été présentée en raison d'une démarche anormale. Un examen a révélé des déficits nerveux crâniens, y compris un réflexe cornéen gravement retardé. Le veau n'était pas ataxique et avait conservé un appétit, mais avait une croissance ralentie pour son âge. Un shunt portosystémique congénital a été diagnostiqué à l'examen post mortem.(Traduit par Isabelle Vallières).