Gallbladder disease in Shetland Sheepdogs: 38 cases (1995-2005)

Gallbladder Mucocele

Gallbladder mucocele (GBM) formation was rarely reported prior to 20 years ago and has emerged as one of the most common, deadly, and poorly understood causes of gallbladder disease in dogs. Multiple and large retrospective studies inform many aspects of diagnosis, concurrent diseases, surgical treatment, complications, and prognosis of patients with GBM. Studies of pathogenesis are fewer but are beginning to disclose underlying mechanisms for GBM formation.

Nutritional Factors Related to Canine Gallbladder Diseases-A Scoping Review

Gallbladder mucocele, cholelithiasis, choledocholithiasis, and cholecystitis are significant contributors to morbidity and mortality in dogs. The exact etiology of these conditions remains poorly understood, though various factors, such as endocrinopathies, dyslipidemia, and impaired gallbladder motility, have been suggested as potential contributors. Surgical intervention has been described as the first choice of treatment when biliary rupture or obstruction is suspected; however, medical management may be an important part of therapeutic or preventative strategy. Reports of medical management typically involve the use of a choleretic used to stimulate the flow of bile into the duodenum or substances that act as a "hepatoprotective" agent such as S-adenosylmethionine. In people, some nutrients appear to modify bile flow and are used as agents in the prevention and treatment of these conditions in the gallbladder. This paper provides a review of the literature about possible nutritional factors involved in the pathogenesis and treatment of canine gallbladder mucocele and cholelithiasis. Opportunities for the prevention and treatment of common biliary diseases in dogs may include the reduction of dietary fat, control of hyperlipidemia with omega-3 and fiber supplementation, ensuring an adequate supply of amino acids such as methionine and tryptophan, and the evaluation of vitamins such as vitamin D.

Comprehensive gene expression analysis in gallbladder mucosal epithelial cells of dogs with gallbladder mucocele

BACKGROUND

Gallbladder mucocele (GBM) is a common disease in the canine gallbladder. Although the pathogenesis of GBM remains unclear, we recently reported that the excessive accumulation of mucin in the gallbladder is not a result of overproduction by gallbladder epithelial cells (GBECs).

HYPOTHESIS/OBJECTIVES

Changes in the function of GBECs other than the production of mucin are associated with the pathogenesis of GBM. We performed an RNA sequencing (RNA-seq) analysis to comprehensively search for abnormalities in gene expression profiles of GBECs in dogs with GBM.

ANIMALS

Fifteen dogs with GBM and 8 dogs euthanized for reasons other than gallbladder disease were included.

METHODS

The GBECs were isolated from gallbladder tissues to extract RNA. The RNA-seq analysis was performed using the samples from 3 GBM cases and 3 dogs with normal gallbladders, and the gene expression profiles were compared between the 2 groups. Differences in mRNA expression levels of the extracted differentially expressed genes (DEGs) were validated by quantitative reverse transcription polymerase chain reaction (RT-qPCR) using samples of 15 GBM cases and 8 dogs with normal gallbladders.

RESULTS

Comparison of gene expression profiles by RNA-seq extracted 367 DEGs, including ANO1, a chloride channel associated with changes in mucin morphology, and HTR4, which regulates the function of chloride channels. The ANO1 and HTR4 genes were confirmed to be downregulated in the GBM group by RT-qPCR.

CONCLUSIONS AND CLINICAL IMPORTANCE

Our results suggest that GBM may be associated with decreased function of chloride channels expressed in GBECs.

Acquired dysfunction of CFTR underlies cystic fibrosis-like disease of the canine gallbladder

Mucocele formation in dogs is a unique and enigmatic muco-obstructive disease of the gallbladder caused by the amassment of abnormal mucus that bears striking pathological similarity to cystic fibrosis. We investigated the role of cystic fibrosis transmembrane conductance regulatory protein (CFTR) in the pathogenesis of this disease. The location and frequency of disease-associated variants in the coding region of CFTR were compared using whole genome sequence data from 2,642 dogs representing breeds at low-risk, high-risk, or with confirmed disease. Expression, localization, and ion transport activity of CFTR were quantified in control and mucocele gallbladders by NanoString, Western blotting, immunofluorescence imaging, and studies in Ussing chambers. Our results establish a significant loss of CFTR-dependent anion secretion by mucocele gallbladder mucosa. A significantly lower quantity of CFTR protein was demonstrated relative to E-cadherin in mucocele compared with control gallbladder mucosa. Immunofluorescence identified CFTR along the apical membrane of epithelial cells in control gallbladders but not in mucocele gallbladder epithelium. Decreases in mRNA copy number for CFTR were accompanied by decreases in mRNA for the Cl-/[Formula: see text] exchanger SLC26A3, K+ channels (KCNQ1, KCNN4), and vasoactive intestinal polypeptide receptor (VIPR1), which suggest a driving force for change in secretory function of gallbladder epithelial cells in the pathogenesis of mucocele formation. There were no significant differences in CFTR gene variant frequency, type, or predicted impact comparing low-risk, high-risk, and definitively diagnosed groups of dogs. This study describes a unique, naturally occurring muco-obstructive disease of the canine gallbladder, with uncanny similarity to cystic fibrosis, and driven by the underlying failure of CFTR function.NEW & NOTEWORTHY Cystic fibrosis transmembrane conductance regulatory protein (CFTR) genomic variants and expression of mRNA, protein, and electrogenic anion secretory activity of CFTR were characterized in dog gallbladder. Acquired inhibition of CFTR expression by gallbladder epithelium was identified as underpinning a naturally occurring muco-obstructive disease of the dog gallbladder that bears striking pathological similarity to animal models of cystic fibrosis.

Histologic findings of gastrointestinal biopsies and clinical outcome in dogs undergoing cholecystectomy for gallbladder mucoceles: 71 cases (2014-2021)

OBJECTIVES

To determine the presence and categorise the severity of enteritis in dogs with gallbladder mucoceles, and evaluate for any associations with enteritis. This study also aimed to report clinical outcome following cholecystectomy and evaluate for associations with survival.

MATERIALS AND METHODS

Medical records were retrospectively reviewed (2014 to 2021) for dogs undergoing cholecystectomy and duodenal biopsy procedures for gallbladder mucocele. Signalment, bloodwork, abdominal ultrasound findings, surgical details, histology results and outcomes were reported. Surgeries were considered elective or emergent based on each dog's clinical presentation. Enteritis was categorised based on cell type and severity. Inflammation and clinical outcome were statistically evaluated.

RESULTS

Seventy-one dogs met the study criteria. Enteritis was present in 85.9% (61/71) of cases with the majority being lymphoplasmacytic (53.5%). Twelve dogs (16.9%) underwent gastrointestinal biopsies from multiple sites, which revealed the same enteritis type at each location. A total of 87.3% (n = 62) dogs survived, including 90.4% elective and 86% emergent cases. No significant differences in enteritis severity or patient survival were found between elective and emergent cases. Septic peritonitis was diagnosed in two dogs (2.82%). Mortality was significantly associated with leukocytosis, with nonsurviving dogs having a mean WBC count of 27.6 G/L (95% confidence interval: 10.6 to 21.5).

CLINICAL SIGNIFICANCE

Enteritis is present in a majority of dogs with gallbladder mucocele, especially mild to moderate with lymphoplasmacytic cell type. Obtaining a duodenal biopsy had minimal impact on patient outcome. Compared to previous studies, improved survival in emergent cases was noted. Further studies with long-term follow-up are needed to determine if enteropathy-related signs persist after cholecystectomy.

Comparison of fibroblast growth factor 19 concentrations between dogs with and without gallbladder mucoceles

BACKGROUND

Fibroblast growth factor 19 (FGF19) is an enterohepatic hormone the synthesis of which is stimulated by bile acid activation of the nuclear farnesoid X receptor (FXR) in ileal enterocytes. Increased production of FGF19 downregulates hepatocyte bile acid synthesis and gluconeogenesis, while concurrently upregulating hepatocyte glycogenesis and gallbladder (GB) filling. The physiologic impact of this regulatory cycle is illustrated in cholecystectomized humans, in whom the disturbed meal-related flux of GB bile decreases serum FGF19 concentrations.

OBJECTIVE

Determine if serum FGF19 concentrations are lower in dogs with clinical GB mucoceles (GBMs) than in control dogs.

ANIMALS

Seven dogs with GBM diagnosed using abdominal ultrasonography, biochemical markers, and GB histopathology. Forty-two control dogs without gastrointestinal or hepatobiliary disorders also were evaluated. Health status of controls was assessed by physical examination and diagnostic hematologic and biochemical test results.

METHODS

Prospective cross-sectional study to compare fasting plasma or serum FGF19 concentrations between groups. Concentrations of FGF19 were quantified by a commercially available FGF19 ELISA.

RESULTS

Concentrations of FGF19 were significantly lower in dogs with clinical GBM (median, 14.0 pg/mL; range, 12.8-67.2) than in control dogs (median, 145.3 pg/mL; range, 36.5-285.1).

CONCLUSIONS AND CLINICAL IMPORTANCE

In dogs, GBM is associated with significantly decreased serum FGF19 concentrations. We speculate that this finding reflects compromised GB contraction and decreased enterohepatic circulation of bile flow. Subnormal FGF19 concentrations may influence bile acid synthesis and hepatic metabolism.

Intrahepatic Duct Incision and Closure for the Treatment of Multiple Cholelithiasis in a Dog

This report describes the successful intrahepatic duct incision and closure for the treatment of multiple cholelithiasis in a dog with untreated hypothyroidism. A 12-year-old spayed female Spitz dog weighing 11.3 kg was diagnosed with multiple cholelithiasis, and a quadrate liver lobectomy and cholecystectomy were performed. Large gallstones were located in the left liver lobe's intrahepatic duct distal to the anastomosis of the intrahepatic ducts of the left medial and lateral lobes. The dilated intrahepatic duct was packed off with wet gauze, and incision and closure were performed on the most dilated section, which was proximal to the largest gallstone. After surgery, the patient showed normal liver function and was discharged with normal total bilirubin and C-reactive protein levels. On postoperative day 83, no stones were observed in the dilated common bile duct (CBD), and the degree of dilatation of the CBD had decreased from 9 mm to 4 mm, with no obstructions. Right intrahepatic gallstones were confirmed without dilatation. Hypothyroidism was managed medically. Hepatic duct incision and closure can be performed in dogs with multiple cholelithiasis. Although not the first option, intrahepatic bile duct incision proves to be a new alternative for the successful treatment of cholelithiasis in dogs.

Increased lipogenesis and lipidosis of gallbladder epithelium in dogs with gallbladder mucocele formation

BACKGROUND

Gallbladder disease in people is frequently associated with disorders of lipid metabolism and metabolic syndrome. A recently emergent gallbladder disease of dogs, referred to as mucocele formation, is characterized by secretion of abnormal mucus by the gallbladder epithelium and is similarly associated with hyperlipidemia, endocrinopathy, and metabolic dysfunction. The cause of gallbladder mucocele formation in dogs is unknown.

METHODS

A prospective case-controlled study was conducted to gain insight into disease pathogenesis by characterization of plasma lipid abnormalities in 18 dogs with gallbladder mucocele formation and 18 age and breed matched control dogs using direct infusion mass spectrometry for complex plasma lipid analysis. This analysis was complemented by histochemical and ultrastructural examination of gallbladder mucosa from dogs with gallbladder mucocele formation and control dogs for evidence of altered lipid homeostasis of the gallbladder epithelium.

RESULTS

Gallbladder mucocele formation in dogs carried a unique lipidomic signature of increased lipogenesis impacting 50% of lipid classes, 36% of esterified fatty acid species, and 11% of complex lipid species. Broad enrichment of complex lipids with palmitoleic acid (16:1) and decreased abundance within complex lipids of presumptive omega-3 fatty acids eicosapentaenoic (20:5) and docosahexaenoic (22:6) was significant. Severe lipidosis of gallbladder epithelium pinpoints the gallbladder as involved causally or consequently in abnormal lipid metabolism.

CONCLUSION

Our study supports a primary increase in lipogenesis in dogs with mucocele formation and abnormal gallbladder lipid metabolism in disease pathogenesis.

Determining the patency of biliary tracts in dogs with gallbladder mucocele using near-infrared cholangiography with indocyanine green

Cholecystectomy is indicated for gallbladder mucoceles (GBM). Evaluating the patency of the biliary duct and precise biliary tree visualization is crucial for reducing the risk of compromised bile flow after surgery. Therefore, intraoperative cholangiography (IOC) is recommended during cholecystectomy to prevent biliary tract injury. Although indocyanine green (ICG) cholangiography has been extensively reported in human medicine, only one study has been conducted in veterinary medicine. Therefore, this study aimed to demonstrate the use of ICG for IOC to identify fluorescent biliary tract images and determine the patency of the common bile duct during cholecystectomy in dogs. This study comprised 27 dogs, consisting of 17 with gallbladder mucoceles (GBM) and 10 controls, specifically including dogs that had undergone elective cholecystectomy for GBM. ICG injection (0.25 mg/kg) was administered intravenously at least 45 minutes before surgery. During the operation, fluorescent images from cholangiography were displayed on the monitor and obtained in black-and-white mode for the comparison of fluorescence intensity (FI). The FI values of the gallbladders (GBs) and common bile duct (CBD) were measured using FI analyzing software (MGViewer V1.1.1, MetapleBio Inc.). The results demonstrated successful CBD patency identification in all cases. Mobile GBM showed partial gallbladder visibility, whereas immobile GBM showed limited visibility. Additionally, insights into the adequate visualization of the remaining extrahepatic biliary tree anatomy were provided, extending beyond the assessment of CBD patency and gallbladder intensity. Our study demonstrates the potential of fluorescent IOC using intravenous injection of ICG for assessing the patency of the cystic duct and common bile duct during cholecystectomy in patients with GBM, eliminating the need for surgical catheterization and flushing of the biliary ducts. Further research is warranted to investigate and validate the broader applicability of ICG cholangiography in veterinary medicine.

An Association between Pancreatic and Cholestatic Biliary Disorders in Dogs

Canine chronic biliary tree disease (CBTD) is a suspected risk factor for pancreatic injury. The aim of this study was to evaluate the frequency and features of pancreatic involvement in canine CBTD, and their relationship with hyperlipemia and its severity. CBTD was defined as the increase in at least two of ALP, GGT, total bilirubin, cholesterol, and a biliary tree abnormal abdominal ultrasound (graded mild to severe). Pancreatic ultrasound appearance was recorded and classified as acute/chronic. Dogs were divided into a PBD group (pancreatic and biliary disease) and BD group (only biliary tree disease). PBD group was subgraded into a "pancreatic injury" and "pancreatitis" group. Eighty-one dogs were retrospectively included: 56 in the PBD group and 25 in the BD group. Of the PBD group, 20 had pancreatitis (15 chronic and 5 dogs acute). US score was mild in 64 dogs and moderate in 17 dogs, and it was not associated with evidence of pancreopathy. Sixty-six dogs had hyperlipemia (mild = 27 dogs; moderate-to-severe = 39 dogs) and no association with pancreopathy was found. Pancreatic injury was more frequent than pancreatitis in CBTD dogs. Although both acute and chronic pancreatic injury may be present, chronic forms were more frequent. Pancreatic injury should be considered in CBTD patients due its possible clinical significance.

Concurrent hepatopathy in dogs with gallbladder mucocele: Prevalence, predictors, and impact on long-term outcome

BACKGROUND

Information is limited regarding the prevalence and importance of hepatic histologic abnormalities in dogs with gallbladder mucocele (GBM).

OBJECTIVES

To (a) report prevalence of hepatic histologic abnormalities in dogs with GBM (b) evaluate for association between hepatic abnormalities and outcome in dogs with GBM (c) evaluate whether neutrophil-to-lymphocyte ratio (NLR) differs in dogs with GBM with and without specific hepatic lesions.

ANIMALS

Fifty-two dogs with grossly and histologically confirmed GBM.

METHODS

Multicenter, retrospective study of dogs with GBM undergoing cholecystectomy with concurrent liver biopsy. Archived histological sections of gallbladder and liver evaluated by investigators blinded to data. Proportions of dogs with each histologic abnormality alive vs deceased at 1, 3, and 12 months post-cholecystectomy compared. Mann-Whitney U performed to determine if NLR differed in dogs with or without selected lesions.

RESULTS

51/52 (98%, 95% CI [89%, 99%]) dogs with GBM had at least 1 hepatic histologic abnormality. Hepatic fibrosis (37/51; 73%, 95% CI [59%, 83%]), biliary hyperplasia (29/52; 56%, 95% CI [42%, 68%]), and portal inflammation (25/52; 48%, 95% CI [35%, 61%]) were most common. The proportion of dogs alive vs dead differed based on the fibrosis score at 1, 3, and 12 (P ≤ .04) months post-cholecystectomy. Dogs with hepatic necrosis (P = .006) and cholangitis/cholangiohepatitis (P = .02) had higher NLRs compared to dogs without these lesions.

CONCLUSIONS AND CLINICAL IMPORTANCE

Histologic abnormalities of the liver are common in dogs with GBM. A higher portal fibrosis score might be associated with shortened long-term survival after cholecystectomy for dogs with GBM. An increase in NLR might predict hepatic necrosis and cholangitis/cholangiohepatitis in dogs with GBM.

MUC5AC and MUC5B expression in canine gallbladder mucocele epithelial cells

Gallbladder mucocele (GBM) is one of the most common gallbladder diseases in dogs. Its pathogenesis has not yet been clarified, but excessive accumulation of a secretory gel-forming mucin, MUC5AC in the gallbladder has been reported. This study aimed to ascertain if MUC5AC overproduction resulted in mucus accumulation in the gallbladder during GBM development. Eleven dogs undergoing cholecystectomy who were pathologically diagnosed with GBM were included, and the expression level of mucins, particularly MUC5AC and MUC5B, in their gallbladder epithelial cells was compared with those in normal gallbladder epithelial cells. On reverse transcription-quantitative polymerase chain reaction screening, there was a significant difference (P<0.05) in the mRNA expression level of MUC1, but not of other mucins including MUC5AC and MUC5B, between mucocele and normal gallbladder epithelial cells. Protein expression levels were also evaluated for MUC5AC and MUC5B using immunohistochemistry. There was little immunoreactivity for MUC5AC, whereas MUC5B showed definitive staining in gallbladder epithelial cells. There was no difference in MUC5AC and MUC5B protein expression levels between mucocele and normal gallbladder epithelial cells. These data suggest that excessive production of mucin, especially MUC5AC and MUC5B, does not occur in canine GBM, and that abnormal mucus excretion, rather than excessive mucus production, may be the cause of GBM development.

Risk factors influencing death prior to discharge in 302 dogs undergoing unilateral adrenalectomy for treatment of primary adrenal gland tumours

Adrenalectomies for canine adrenal tumours are associated with peri-operative morbidity and mortality. Objectives of this study included assessing the prognostic value of tumour- or surgery-related variables in predicting peri-operative mortality and overall survival in dogs undergoing adrenalectomies for primary adrenal tumours as well as pre-treatment with phenoxybenzamine on survival to discharge with pheochromocytomas specifically. A multi-institutional retrospective cohort study was performed across nine institutions. Electronic medical record searches identified 302 dogs which met the inclusion criteria. Data collected included dog-related, tumour-related, treatment-related, surgery-related, and outcome variables. Univariate and multivariable logistic regression and cox proportional hazards models were used to identify variables associated with death prior to discharge and tumour-related survival. Overall, 87% of dogs survived to discharge with a tumour-related survival time of 3.96 years. Post-operative complications were reported in 25%. Increased surgical time (p = 0.002) and pre-surgical medical treatment other than phenoxybenzamine (p = 0.024) were significantly associated with increased peri-operative mortality while ureteronephrectomy (p = 0.021), post-operative pancreatitis (p = 0.025), and post-operative aspiration pneumonia (p < 0.001) were significantly associated with decreased overall survival. Phenoxybenzamine pretreatment had no effect on peri-operative mortality. Thirty-seven of 45 (82%) dogs with pheochromocytomas not pretreated survived to discharge, and 50 of 59 (85%) dogs with pheochromocytomas pretreated with phenoxybenzamine survived to discharge (p = 0.730). This study provides information on risk factors for death prior to discharge and tumour-related survival that may help guide clinical management and owner expectations. In addition, the study findings challenge the previously reported benefit of phenoxybenzamine for pretreatment of dogs undergoing adrenalectomies for pheochromocytomas.

Occurrence and clinical relevance of postoperative hypernatremia in dogs undergoing cholecystectomy

BACKGROUND

Patients undergoing cholecystectomy have not been reported previously to develop clinically relevant postoperative hypernatremia.

OBJECTIVES

Describe the frequency of postoperative hypernatremia in dogs undergoing cholecystectomy and its clinical relevance (duration of hospitalization and survival).

ANIMALS

Thirty-seven dogs undergoing cholecystectomy at 2 private referral hospitals.

METHODS

Retrospective study of dogs undergoing cholecystectomy with available preoperative and postoperative serum sodium concentrations.

RESULTS

Postoperative hypernatremia (>150 mEq/L) was common (56%; 95% confidence interval [CI], 40%-70%) and was associated with significantly higher mortality compared to nonhypernatremic patients (52%; 95% CI, 30%-70% vs 12.5%; 95% CI, 2%-40%; P = .02). Nonsurvivors had higher mean postoperative peak serum sodium concentrations (155 mEq/L; range, 146-172) than survivors (150 mEq/L; range, 142-156; P = .01). Dogs developing hypernatremia within 6 hours after surgery had 7.7 higher odds of nonsurvival (odds ratio [OR], 7.7; 95% CI, 5.9-9.4). A delta value (serum sodium concentration on admission [T0] - serum sodium concentration 6 hours postoperatively [T2]) of ≥10 mEq/L carried 3.3 higher odds of mortality (OR, 3.3; 95% CI, 1.6-5.1). All dogs with a postoperative peak sodium concentration >160 mEq/L did not survive. Admission acute patient physiologic laboratory evaluation fast (APPLEfast ) scores were not different between survivors and nonsurvivors or between postoperative hypernatremic and normonatremic patients. Hospitalization time was no different between hypernatremic and normonatremic patients (6 days vs 4.5 days; P = .15). Dogs with gallbladder mucocele were more likely to develop postoperative hypernatremia and have poorer outcomes.

CONCLUSIONS

Hypernatremia was a common and clinically relevant postoperative complication in dogs after cholecystectomy. Detection of hypernatremia within 6 hours after surgery may be associated with poorer outcomes.

Gallbladder microbiota in healthy dogs and dogs with mucocele formation

To date studies have not investigated the culture-independent microbiome of bile from dogs, a species where aseptic collection of bile under ultrasound guidance is somewhat routine. Despite frequent collection of bile for culture-based diagnosis of bacterial cholecystitis, it is unknown whether bile from healthy dogs harbors uncultivable bacteria or a core microbiota. The answer to this question is critical to understanding the pathogenesis of biliary infection and as a baseline to exploration of other biliary diseases in dogs where uncultivable bacteria could play a pathogenic role. A pressing example of such a disease would be gallbladder mucocele formation in dogs. This prevalent and deadly condition is characterized by excessive secretion of abnormal mucus by the gallbladder epithelium that can eventually lead to rupture of the gallbladder or obstruction of bile flow. The cause of mucocele formation is unknown as is whether uncultivable, and therefore unrecognized, bacteria play any systematic role in pathogenesis. In this study we applied next-generation 16S rRNA gene sequencing to identify the culture-negative bacterial community of gallbladder bile from healthy dogs and gallbladder mucus from dogs with mucocele formation. Integral to our study was the use of 2 separate DNA isolations on each sample using different extraction methods and sequencing of negative control samples enabling recognition and curation of contaminating sequences. Microbiota findings were validated by simultaneous culture-based identification, cytological examination of bile, and fluorescence in-situ hybridization (FISH) performed on gallbladder mucosa. Using culture-dependent, cytological, FISH, and 16S rRNA sequencing approaches, results of our study do not support existence of a core microbiome in the bile of healthy dogs or gallbladder mucus from dogs with mucocele formation. Our findings further document how contaminating sequences can significantly contribute to the results of sequencing analysis when performed on samples with low bacterial biomass.

Clinical findings and assessment of factors associated with survival in dogs presenting with hyperbilirubinaemia: 115 cases in Victoria, Australia (2015-2020)

Introduction

Hyperbilirubinaemia is an important clinicopathological finding in canine medicine. The objectives of this study were to describe the clinical presentation and outcome of dogs with hyperbilirubinaemia; also to identify factors associated with survival.

Materials and methods

Retrospective study of dogs with hyperbilirubinaemia from two referral centres in South Australia (2015-2020). Signalment, clinical signs, clinicopathological data, diagnosis and outcome were obtained from searching clinical records. Univariable analysis and logistic regression modelling were used to compare outcomes and overall survival.

Results

A total of 115 cases were included. The most common clinical signs were vomiting (63.5%), anorexia (62.6%), lethargy (55.7%) and pyrexia (18.3%). Pre-hepatic icterus was diagnosed in 18 cases (15.7%), hepatic icterus in 51 cases (44.3%) and post-hepatic icterus in 42 cases (36.5%). The median survival time across all cases was 40 days (95% confidence interval [CI]: 9-126 days). There was an increased risk of death in dogs with serum bilirubin greater than 60 μmol/L at diagnosis (odds ratio [OR] = 3.55; 95% CI: 1.53-8.22; p-value = 0.003) and in dogs with pre-hepatic icterus compared to hepatic (OR = 4.35; 95% CI: 1.18-16.0; p-value = 0.027) and post-hepatic icterus (OR = 6.52; 95% CI: 1.67-25.5; p-value = 0.007).

Conclusions

Pre-hepatic icterus was associated with a significantly higher risk of death than hepatic and post-hepatic icterus. Serum bilirubin >60 μmol/L at diagnosis was associated with a significantly shorter median survival time. This cut-off may be useful in discussions with owners regarding pursuing further diagnostic investigation and treatment. Further prospective studies are needed to prove the validity of this cut-off.

In Vivo Evaluation of DMSA-Coated Magnetic Nanoparticle Toxicity and Biodistribution in Rats: A Long-Term Follow-Up

This work presents a long-term follow-up (300 days) of rats after a single intravenous injection of DMSA-coated magnetite nanoparticles (DMSA-MNP). The animals were systematically evaluated by hematological, biochemical, and ultrasound examinations, monitoring the same animal over time. In addition, oxidative stress evaluation, DMSA-MNP biodistribution, computerized tomography for ex vivo organs, and histopathology analysis were performed at the end of the experiment period. Overall, DMSA-MNP administration did not cause serious damage to the rats' health over the course of 300 days post-administration. All animals presented hematological parameters within the normal limits, and no alterations on serum creatinine, urea, ALT, and AST were related to DMSA-MNP administration. Liver and spleen showed no important alterations in any of the examinations. The kidneys of treated animals displayed intermittent pelvis dilation at ultrasound analysis, but without damage to the organ parenchyma after 300 days. The lungs of treated animals presented a light interalveolar septal thickening, but the animals did not present any clinical respiratory symptom. Nanoparticles were not detected in the vital organs of treated animals 300 days after administration. This work represents the first assessment of the long-term effects of DMSA-MNP and goes a step further on the safety of its use for biomedical applications.

High frequency of cholecystitis in dogs with gallbladder mucocoele in Hong Kong

The aims of this retrospective study were to characterise the epidemiological, clinical, histopathological, and microbiological findings as well as surgical outcomes in dogs admitted to a specialist veterinary hospital in Hong Kong for surgical management of gallbladder mucocoele (GBM). Inclusion criteria were cases with histopathological diagnosis of GBM and accompanying abdominal imaging, serum biochemistry, bile culture, and liver biopsy histology results. Fifty-six cases met the inclusion criteria. The median age at diagnosis was 12 years (range, 5-16 years). Miniature or toy pure-breed dogs were most commonly affected, including Poodles, Pomeranians, Schnauzers, Bichon frises and Chihuahuas. However, no breed was over-represented compared with their expected proportions among annual hospital admissions. Histological evidence of cholecystitis was present in 84% of cases, including acute cholecystitis in 18%, chronic cholecystitis in 37.5%, acute on chronic cholecystitis in 28% and acute with necrosis in 6%. The most common liver lesions were cholestasis in 64%, along with portal fibrosis in 55%, oedema in 50% and bile duct hyperplasia in 50%. Bile culture was positive in 29.6% of cases. Escherichia coli and Enterobacter species were most commonly isolated. Stentrophomonas maltophili was cultured from one case. Of the 16 cases where bacteria were isolated from bile culture, 94% had evidence of chronic cholecystitis and 81% had evidence of cholangiohepatitis. Fifty dogs (89.3%) survived to discharge including 5/5 dogs with ruptured gallbladders. Of 34 dogs with follow-up data, 21/34 (61.8%) were still alive 12 months later. Gallbladder mucocoeles were frequently associated with both acute and chronic inflammation. High survival rates to discharge were achieved.

A multicenter retrospective study assessing progression of biliary sludge in dogs using ultrasonography

Background

Objectives

Animals

Methods

Results

Conclusions and Clinical Importance

Preoperative serum C-reactive protein concentration can be used to detect gallbladder rupture in dogs with gallbladder mucocele

OBJECTIVE

To determine whether serum C-reactive protein (CRP) concentration could be used to detect gallbladder rupture (GBR) prior to surgery in dogs undergoing cholecystectomy for treatment of gallbladder mucocele (GBM).

ANIMALS

45 dogs that underwent cholecystectomy because of GBM at a companion animal referral hospital from 2017 to 2020.

PROCEDURES

Electronic medical records were reviewed, and dogs were included if serum CRP concentration had been measured within 24 hours prior to cholecystectomy. Dogs were grouped as to whether the gallbladder was found to be ruptured or intact during surgery. Accuracy of using preoperative CRP concentration to predict GBR was compared with accuracy of abdominal ultrasonography and other preoperative blood tests.

RESULTS

GBR was present in 15 dogs at the time of surgery. Median preoperative CRP concentration was significantly higher in dogs with GBR (15.1 mg/dL; interquartile range, 7.4 to 16.8 mg/dL) than in dogs with an intact gallbladder (2.65 mg/dL; interquartile range, 0.97 to 13.4 mg/dL). Sensitivity, specificity, and accuracy of using preoperative CRP concentration to predict GBR were 100%, 67%, and 78%, respectively.

CLINICAL RELEVANCE

Measurement of preoperative CRP concentration provided excellent sensitivity and moderate specificity for detection of GBR in dogs undergoing cholecystectomy because of GBM. Accuracy of using preoperative CRP concentration for detection of GBR was not superior to the accuracy of preoperative abdominal ultrasonography. However, when CRP concentration was combined with results of ultrasonography, the sensitivity, specificity, and accuracy for detection of GBR were 100%, 93%, and 96%, respectively.

Chronic Cholecystitis of Dogs: Clinicopathologic Features and Relationship with Liver

Simple Summary

This study on the gallbladders and livers of 219 client-owned dogs provides a benchmark for future studies on chronic canine cholecystitis. The statistical evaluation of clinical data; histopathology; histochemistry; and immunohistochemistry in this report provides insight into the etiology of chronic cholecystitis in dogs

Abstract

(1) Background: Chronic cholecystitis of dogs has not been vigorously investigated histopathologically. In addition, the relationship between gallbladder and liver diseases is not known. (2) Methods: We aimed to provide a hallmark for canine chronic cholecystitis using clinical data, histopathology, histochemistry, immunohistochemistry, and statistical analysis. (3) Results: Our investigation of 219 ultrasonographically abnormal surgically resected canine gallbladders revealed 189 cases (86.3%) of mucosal lymphoplasmacytic infiltration (chronic cholecystitis). Sludge, a gravity-dependent or nondependent fine granular hyperechoic material, was more prevalent (105/219, 47.9%) than mucocele (51/219, 23.2%) in this cohort. Mucosal lymphoid follicles were detected in 68/219 cases (31%), suggesting the influence of long-standing antigenic stimulation. Bacteria were histochemically detected in 41/60 (68.3%) of heavily inflamed gallbladders, 18/129 (14%) of lightly inflamed, and 3/18 (16.7%) of uninflamed gallbladders, suggesting a possible relationship between bacteria and chronic cholecystitis. Simultaneous liver biopsies revealed mild or no inflammation, changes consistent with primary portal vein hypoplasia, and mild hepatocellular degeneration. (4) Conclusions: Based on the results of our statistical analysis, we conclude that canine chronic cholecystitis is a long-standing inflammatory process of unknown (but possibly bacterial) etiology and that liver pathology is unlikely the cause of chronic cholecystitis in dogs.

Gall bladder ejection fractions in dogs investigated for chronic altered appetite: 14 cases (2015-2017)

OBJECTIVES

To determine if gall bladder dysmotility occurs in dogs investigated for chronic altered appetite and to determine if gall bladder dysmotility warrants further investigation as a contributing factor to altered appetite.

MATERIALS AND METHODS

Case series of dogs investigated for chronic gastrointestinal disease. Gastrointestinal clinical signs were assessed before and after a 6-week hydrolysed protein diet. Gall bladder ejection fractions were determined at the end of the 6-week hydrolysed protein diet as part of an investigation that included a full blood cell count, biochemistry, abdominal X-rays and ultrasound. The gall bladder ejections fraction results of dogs with normal appetite were compared to dogs with general inappetence and dogs with diurnal inappetence in the morning.

RESULTS

In this retrospective case series of 14 dogs, altered appetite was the most frequent and persistent clinical sign associated with chronic gastrointestinal disease. Nine dogs had suboptimal gall bladder function and this occurred in dogs with, and without, gravity-dependent biliary sludge. Gall bladder function and volumes of dogs in this study were comparable to those of dogs with nongravity-dependent gall bladder sludge or gall bladder mucoceles in other studies. There was an observable difference in gall bladder ejection fractions between groups defined by appetite but no statistically significant difference was present. Small sample sizes meant the effect size was large.

CLINICAL SIGNIFICANCE

Gall bladder dysmotility and distension can occur in the absence of gall bladder sludge and mucocoeles in younger dogs. Gall bladder dysmotility requires further investigation as a potential contributing factor to altered appetite in dogs.

Evaluation of coagulation parameters in dogs with gallbladder mucoceles

BACKGROUND

Gallbladder mucocele (GBM) is a common biliary disorder in dogs. Limited information is available on the coagulation status of dogs with GBM.

HYPOTHESIS/OBJECTIVES

To determine patterns of coagulation alterations in dogs with GBM and correlate them with clinicopathologic abnormalities and ultrasonographic findings of disease severity.

ANIMALS

Twenty-three dogs with GBM identified on ultrasound examination were prospectively enrolled.

METHODS

At the time of GBM identification, blood and urine were collected for CBC, serum biochemical panel, urinalysis, prothrombin time, activated partial thromboplastin time (aPTT), factor VIII, protein C (PC), von Willebrand's factor (vWF), antithrombin activity, fibrinogen, D-dimers, and thromboelastrography (TEG). Gallbladder mucoceles were classified into ultrasound types 1 to 5. Medical records were reviewed for clinical presentation, underlying conditions and to determine if systemic inflammatory response syndrome (SIRS) was present.

RESULTS

Based on TEG parameters, maximal amplitude, and G, 19/23 (83%) of dogs with GBM had evaluations consistent with hypercoagulability. On plasma-based coagulation testing, dogs with GBM had increased total PC activity (20/23, 87%), fibrinogen (9/23, 39%), platelet count (9/23, 39%), and D-dimers (6/15, 40%) as well as prolongations in aPTT (9/22, 41%) and low vWF activity (5/21, 24%). No correlation was found between TEG G value and any coagulation or clinical pathology variables, ultrasound stage of GBM or disease severity as assessed by the presence of SIRS.

CONCLUSIONS AND CLINICAL IMPORTANCE

Dogs with ultrasonographically identified GBM have changes in whole blood kaolin-activated TEG supporting a hypercoagulable state although traditional plasma-based coagulation testing suggests that a complex state of hemostasis exists.

Histopathological frequency of canine hepatobiliary disease in the United Kingdom

OBJECTIVES

Canine hepatobiliary disease is common; however, data determining disease frequency and breed predispositions are lacking. The primary objective was to identify the frequency of different hepatobiliary disease in a United Kingdom population of dogs and consequently determine breeds at both an increased and decreased risk of hepatobiliary disease.

MATERIALS AND METHODS

Anonymised histopathology reports from a commercial veterinary diagnostic laboratory, which were submitted between August 2013 and February 2018, were analysed. Data were retrospectively categorised into hepatobiliary diseases according to World Small Animal Veterinary Association Standards and the breed, age and genders recorded. Cases with incomplete data or no definitive diagnosis were excluded. Breed predisposition was calculated using odds ratios and 95% confidence intervals against a United Kingdom-based control population of micro-chipped dogs.

RESULTS

Histopathology results from 4584 cases met inclusion criteria. The most frequent histological diagnoses were reactive hepatitis (n=770); chronic hepatitis (n=735) and reversible hepatocellular injury (n=589). A number of breeds were shown to be at an increased or decreased risk of individual liver diseases.

CLINICAL SIGNIFICANCE

This is the first study to document the histopathological frequency of hepatobiliary diseases in a large cohort of dogs in the United Kingdom, as well as novel possible breed and age predispositions. Despite multivariable analysis not being performed to account for confounding factors, this information hopes to inform and support future investigations for hepatic disease in particular breeds and potential predispositions.

Efficacy of a micronized, nanocrystal fenofibrate formulation in treatment of hyperlipidemia in dogs

Background

Safe, effective, and readily available drug therapies are required for the management of hyperlipidemia and its associated complications in dogs.

Objectives

To investigate the efficacy of a micronized, nanocrystal formulation of fenofibrate (Tricor) in the treatment of hyperlipidemia in dogs.

Animals

Ten client‐owned dogs with primary (n = 7) and secondary (n = 3) hyperlipidemia. All dogs had hypertriglyceridemia at baseline; 3 dogs also had hypercholesterolemia.

Methods

Prospective dose‐escalation study. Dogs were treated with fenofibrate orally once daily in up to 3 cycles of 21 days each. Fenofibrate dose was increased at the end of each cycle if hypertriglyceridemia persisted and adverse effects were not documented. Complete blood count, biochemistry, and urine protein:creatinine ratio were collected serially. Baseline (T0) parameters were compared to time of maximal reduction in serum triglyceride concentrations (T1) and reported as median (range).

Results

Triglycerides normalized in all dogs (T0 = 662 mg/dL [189‐2391]; T1 = 113 mg/dL [81‐132]; P = .002). Fenofibrate dose at T1 = 6.4 mg/kg PO q24h (range, 2.2‐13.5). T1 was achieved at 3 (n = 4), 6 (n = 4), and 9 (n = 2) weeks. Serum cholesterol concentrations decreased in 9 of 10 dogs. Quiet demeanor and firm stools in 1 dog were the only reported adverse reactions. Fenofibrate administration resulted in a significant reduction in median alkaline phosphatase activity (P = .049).

Conclusions and Clinical Importance

Over 21 to 63 days, TriCor was effective in the management of primary and secondary hyperlipidemia in dogs.

Influence of normograde versus retrograde catheterization of bile ducts in dogs treated for gallbladder mucocele

OBJECTIVE

To determine the influence of normograde (NG) versus retrograde (RG) catheterization of the cystic duct and common bile duct (CBD) in dogs with gallbladder mucoceles (GBM) treated with open cholecystectomy.

STUDY DESIGN

Retrospective study.

ANIMALS

Dogs (n = 117) with GBM.

METHODS

Medical records were reviewed for signalment, history, clinical laboratory and diagnostic imaging findings, details of surgery including catheterization method, complications, and outcome. Long-term follow-up data were obtained by telephone or electronic communication. Relationships between catheterization method and clinical variables and outcome were evaluated.

RESULTS

Dogs catheterized RG were more likely to experience any postoperative complication (p = .0004) including persistence of gastrointestinal signs (p = .0003). Survival to discharge and long-term survival did not differ by group (p = .23 and p = .49). Total bilirubin (TB) decreased by 70.3% after NG catheterization compared to 39.1% after RG catheterization (p = .03) and increased in 14.9% dogs catheterized NG and 38.0% dogs catheterized RG (p = .004). The presence of a diplomate surgeon at surgery resulted in decreased incidences of any perioperative or postoperative complication (p = .003 and p = .05).

CONCLUSION

Retrograde catheterization was associated with more postoperative concerns than NG catheterization, but similar survival times. Surgery should be performed by diplomates experienced in biliary surgery to minimize complications.

CLINICAL SIGNIFICANCE

Although both NG and RG techniques to catheterize the cystic duct and CBD are options for treatment of GBM with low mortality, results of this study provide some evidence to recommend NG over RG catheterization.

Comprehensive Review of Biliary Peritonitis

Biliary peritonitis is a growing concern in the canine patient and a thorough understanding of the disease will lead to better treatment outcomes. This article reviews the human and veterinary literature pertaining to biliary peritonitis including both scientific reviews and original publications. Compared to human medicine, biliary peritonitis can be difficult to diagnose preoperatively. Multiple risk factors exist increasing the likelihood of development of biliary peritonitis. Treatment recommendations center on stabilization, surgical cholecystectomy, and postoperative supportive care. Clinically, further studies on treatment and prevention in veterinary medicine are warranted.

Clinical characteristics and histology of cholecystectomised dogs with nongravity-dependent biliary sludge: 16 cases (2014-2019)

OBJECTIVES

To report the available histology, biochemistry and clinical progression of dogs without classic overt biliary tract signs that underwent cholecystectomy for nongravity-dependent biliary sludge.

MATERIALS AND METHODS

Case series of client-owned dogs for which a cholecystectomy was performed for nongravity-dependent biliary sludge. In six dogs, for which nongravity-dependent biliary sludge filled less than half of gall bladder volume, gall bladder ejection fractions were measured. Available histology, biochemistry, presenting clinical signs and post-surgical clinical progression were reported.

RESULTS

Sixteen dogs were included in this retrospective case series. No dogs met the histological criteria for gall bladder mucocoeles or had histological evidence of primary hepatitis or cholangitis. Biochemistry was normal for 11 dogs. Hypercholesterolaemia was not noted in any dog. Twelve dogs had cholecystitis (11 lymphoplasmacytic, one neutrophilic) and nine dogs had biliary mucosal hyperplasia. Thirteen dogs had enteritis (12 lymphoplasmacytic, one eosinophilic) and nine dogs had reactive hepatitis (eight lymphoplasmacytic, one neutrophilic). All six dogs with nongravity-dependent biliary sludge that filled less than half of gall bladder volume had sub-optimal gall bladder function. Presenting clinical signs, including diurnal inappetence in the morning and exercise intolerance, resolved in 86% (12/14) of dogs after cholecystectomy and clinical improvement was noted in 81% (13/16) of dogs overall.

CLINICAL SIGNIFICANCE

Duodenal inflammation could potentially impact gall bladder dysmotility in dogs with nongravity-dependent biliary sludge. Furthermore, diurnal inappetence in the morning and exercise intolerance could indicate symptomatic gall bladder disease in dogs with NDBS and can potentially precede more obvious systemic clinical signs associated with gall bladder mucocoeles.

Clinical findings for dogs undergoing elective and nonelective cholecystectomies for gall bladder mucoceles

OBJECTIVES

The purpose of this study was to describe elective and nonelective post-cholecystectomy complications and mortality rates in dogs with a gall bladder mucocele. The secondary purpose was to report complications and mortality rates for different methods of common bile duct catheterisation.

MATERIALS AND METHODS

A multi-institutional retrospective case series was performed to identify dogs with a gall bladder mucocele between 2004 and 2018 that underwent a cholecystectomy. Dogs were classified into nonelective or elective based on the presence or absence, respectively, of gall bladder rupture, biliary duct distension, clinical signs or hyperbilirubinemia. Each cholecystectomy was classified into three groups: duodenotomy and retrograde catheterisation, normograde catheterisation or no catheterisation. Complications were divided into four grades based on increasing severity and mortality rates were assessed for each.

RESULTS

The mortality rate was 2 (6%) out of 31 for dogs undergoing an elective cholecystectomy and 21 (23%) out of 90 for dogs undergoing a nonelective cholecystectomy. The complication rate was 52% for the elective cholecystectomy and 50% for nonelective cholecystectomy. The majority of the complications in the elective category were grade 1 (mild). Post-operative hyperthermia developed in 35% of dogs that had a duodenotomy and retrograde common bile duct catheterisation, in 4% of dogs with a normograde common bile duct catheterisation and in 7% of dogs that did not have the common bile duct catheterised.

CLINICAL SIGNIFICANCE

Elective cholecystectomy in dogs with a gall bladder mucocele in this study carried a low mortality rate and a relatively high frequency of minor complications.

Proteinuria in dogs with gallbladder mucocele formation: A retrospective case control study

Background

Proteinuria is an independent risk factor for morbidity and mortality in dogs. An association between proteinuria and gallbladder mucocele formation in dogs is unknown.

Objective

Determine if gallbladder mucocele formation or clinicopathologic comorbidities are associated with proteinuria.

Animals

Twenty‐five dogs with mucocele formation and 25 breed and age‐matched control dogs from a prior study.

Methods

Retrospective case control study. Proteinuria defined by calculated urine dipstick protein concentration (mg/mL) to urine specific gravity (USG) ratio. Clinicopathologic findings, postcosyntropin cortisol concentration, thyroid function profile, and illness severity score were recorded.

Results

Median urine dipstick protein concentration to USG ratio and number of dogs having a ratio ≥1.5 were significantly higher for dogs with mucocele formation compared to control dogs. Proteinuria was not significantly associated with CBC or serum biochemistry profile abnormalities but increased in relation to severity of illness.

Conclusions and Clinical Importance

Gallbladder mucocele formation is significantly associated with proteinuria in dogs. Diagnosis and treatment of proteinuria in dogs with mucocele formation might minimize long term kidney morbidity in these patients.

Dogs with biliary rupture based on ultrasound findings may have normal total serum bilirubin values

The absence of hyperbilirubinemia can lead to decreased suspicion of biliary rupture in dogs. This delay of suspicion and treatment can result in increased mortality rates. The objective of this retrospective, observational study was to describe ultrasound and serum bilirubin findings in a group of dogs with an ultrasonographic diagnosis of suspected biliary rupture. The records of a single institution were searched over the period of 2007-2019 for cases having ultrasound reports describing suspicion of biliary rupture. Clinical findings for each of the cases were recorded. A total of 35 dogs met inclusion criteria and, of these, 30 dogs had confirmed ruptured biliary tracts. It was found that 40% (12/30) of dogs with confirmed ruptured biliary tracts had a serum bilirubin values within the normal reference range. No statistical difference was found in serum bilirubin values between the ruptured and nonruptured biliary tracts. Leukocytosis and neutrophilia were found to be statistically significant between ruptured and nonruptured biliary tracts. Mucinous material, similar to "white bile" found in human literature, was found within the peritoneal effusion of six dogs with biliary rupture, three of which also lacked bile pigment. Findings from this study indicated that normobilirubinemia may be present in some dogs with biliary rupture, and therefore should not be used as a reason for excluding this differential diagnosis.

Serum 25-hydroxyvitamin D concentrations in dogs with gallbladder mucocele

Gallbladder mucocele (GBM) is a common biliary disorder in dogs. Gallbladder hypokinesia has been proposed to contribute to its formation and progression. The specific cause of gallbladder stasis in dogs with GBM as well as viable treatment options to resolve dysmotility remains unknown. Vitamin D deficiency is one of the many potential causes of gallbladder hypokinesia in humans and repletion results in complete resolution of stasis. Improving our understanding of the relationship between serum vitamin D and GBM could help identify dogs as a model for humans with gallbladder hypokinesia. Furthermore, this relationship could provide insight into the pathogenesis of GBM and support the need for future studies to investigate vitamin D as a novel treatment target. Therefore, goals of this study were i) to determine if serum 25-hydroxyvitamin(OH)D concentrations were decreased in dogs with GBM, ii) if serum 25(OH)D concentrations were different in clinical versus dogs subclinical for GBM, and iii) to determine if serum 25(OH)D concentrations could predict the ultrasonographic type of GBM. Sixty-two dogs (clinical, n = 26; subclinical, n = 36) with GBM and 20 healthy control dogs were included in this prospective observational study. Serum 25(OH)D concentrations were measured with a competitive chemiluminescence immunoassay. Overall, dogs with GBM had lower serum 25(OH)D concentrations than control dogs (P = 0.004). Subsequent subgroup analysis indicated that this difference was only significant in the subclinical group compared to the control dogs (P = 0.008), and serum 25(OH)D concentrations did not significantly differ between dogs clinical for GBM versus subclinical or control dogs, indicating that inflammatory state in clinical dogs was not the major constituent of the observed findings. Decreasing serum 25(OH)D concentrations, but not clinical status, was associated with a more advanced developmental stage of GBM type determined by ultrasonography. Our results indicate that vitamin D has a role in dogs with GBM. Additional studies are needed to assess if reduced vitamin D in dogs with GBM is a cause or effect of their biliary disease and to investigate if vitamin D supplementation could be beneficial for dogs with GBM.

Association between biliary tree manipulation and outcome in dogs undergoing cholecystectomy for gallbladder mucocele: A multi-institutional retrospective study

OBJECTIVE

To determine whether catheterization of the common bile duct (CBD) is associated with outcome in dogs undergoing cholecystectomy for gallbladder mucocele and to determine whether this association is modified by the catheterization method.

STUDY DESIGN

Multi-institutional retrospective cohort study.

ANIMALS

Dogs (n = 252) that underwent cholecystectomy for gallbladder mucocele.

METHODS

Dogs were identified via electronic medical record review at four veterinary teaching hospitals. Baseline dog characteristics, surgical findings, and methods including normograde vs retrograde CBD catheterization, intraoperative outcomes, and postoperative outcomes and complications were recorded. Variables were compared between dogs with and without catheterization.

RESULTS

Catheterized dogs had higher American Society of Anesthesiologists scores (P = .04), higher total bilirubin (P = .01), and were more likely to have dilated CBD at the time of surgery (P < .01). Incidence of major and minor intraoperative complications was similar between the two groups. Surgical time was longer for the catheterized group (P = .01). The overall incidence of postoperative complications was similar between the groups; however, postoperative pancreatitis was associated with performing CBD catheterization (P = .01). This association was retained as an independent association in a multivariable model that addressed baseline group differences (P = .04). Likelihood of developing postoperative pancreatitis was not different between normograde and retrograde catheterization (P = .57).

CONCLUSION

Catheterization of the CBD was associated with development of postoperative pancreatitis. This was not influenced by the method of catheterization.

CLINICAL SIGNIFICANCE

The requirement for catheterization of the CBD during open cholecystectomy in dogs should be carefully considered, particularly in dogs without evidence of biliary obstruction because the procedure may induce postoperative pancreatitis.

Effect of a low-fat diet on serum triglyceride and cholesterol concentrations and lipoprotein profiles in Miniature Schnauzers with hypertriglyceridemia

Background

Hypertriglyceridemia is common in Miniature Schnauzer (MS). Dietary management of hypertriglyceridemia is important, but no studies are available.

Hypothesis/Objectives

To evaluate the effect of a commercially available low‐fat diet on serum triglyceride and cholesterol concentrations and lipoprotein profiles in MS with hypertriglyceridemia.

Animals

Sixteen MS with hypertriglyceridemia and 28 MS without hypertriglyceridemia.

Methods

Prospective clinical trial. Four blood samples (1‐2 months before and 1 day before diet change and 2 and 3 months after the dogs were fed the low‐fat diet) were collected from the MS with hypertriglyceridemia.

Results

Serum triglyceride concentrations for the 2 samples after the diet change (median of sample 3 = 177 mg/dL; range, 48‐498; median of sample 4 = 168 mg/dL; range, 77‐745) were significantly lower than the 2 samples before the diet change (median of sample 1 = 480 mg/dL; range, 181‐1320; median of sample 2 = 493 mg/dL; range, 114‐1395; P < .001). Serum cholesterol concentrations for the 2 samples after the diet change (mean for sample 3 = 257 mg/dL, SD = 82.2; mean for sample 4 = 178 mg/dL, SD = 87.4) were also significantly lower than the 2 samples before the diet change (mean for sample 1 = 381 mg/dL, SD = 146.1; mean for sample 2 = 380 mg/dL, SD = 134.7; P < .001). Before the diet change, 15/16 (94%) of hyperlipidemic MS were classified as hyperlipidemic based on their lipoprotein profiles alone. After the diet change, significantly fewer MS (7/16; 44%; odds ratio = 19.3; 95% CI = 2.0‐184.0; P = .006) were classified as hyperlipidemic based on lipoprotein profile analysis.

Conclusions and Clinical Importance

The study diet was effective in reducing serum triglyceride and cholesterol concentrations and correcting lipoprotein profiles in MS with hypertriglyceridemia.

Clinical and Prognostic Findings in Dogs with Suspected Extrahepatic Biliary Obstruction and Pancreatitis

Pancreatitis in dogs may lead to extrahepatic bile duct obstruction as a result of local inflammation. Medical records of 45 client-owned dogs with clinical suspicion of extrahepatic bile duct obstruction secondary to pancreatitis were reviewed to determine clinical findings, outcome, and factors associated with survival. Survival times were determined using the Kaplan-Meier product limit method. Cox multivariable survival methods were employed to determine factors associated with survival time following diagnosis. The median survival time was 241 days (95% confidence interval [CI] 25–631), with 34 of 45 dogs (76%) surviving to discharge. Dogs 9 yr of age or older with azotemia at presentation had a 9.9 greater hazard for death (95% CI 2.5–38.1; P = .001) compared with dogs younger than 9 yr old without azotemia at presentation. Dogs without subjective ultrasonographic gallbladder distension had a 4.4 greater hazard for death (95% CI 1.3–15.4; P = .018) compared with dogs with subjective gallbladder distension. Dogs with a body temperature ≥102.5°F at admission had a 3.1 greater hazard for death (95% CI 1.3–7.7; P = .013) than dogs with a body temperature &lt;102.5°F at admission. This information may help clinicians discuss prognosis with owners of affected dogs.

Serological markers of gluten sensitivity in Border terriers with gall bladder mucocoeles

OBJECTIVES

To evaluate serological markers of gluten sensitivity in conjunction with cholecystokinin measurement in Border terriers with gall bladder mucocoeles.

MATERIALS AND METHODS

Medical records from two referral hospitals were obtained between 2011 and 2019 to identify Border terriers with gall bladder mucocoeles, non-Border terriers with gall bladder mucocoeles and control Border terriers with non-biliary diseases. Enzyme-linked immunosorbent assays were performed on stored fasted serum samples for anti-gliadin IgG, anti-canine transglutaminase-2-IgA autoantibodies and cholecystokinin. Statistical analysis was performed using the Kruskall-Wallis test to identify differences between the groups.

RESULTS

Fifteen Border terriers with gall bladder mucocoeles, 17 non-Border terriers with gall bladder mucocoeles and 14 control Border terriers with non-biliary diseases were recruited. Median transglutaminase-2-IgA autoantibodies in Border terriers with gall bladder mucocoeles was 0.73 (range: 0.18 to 1.67), which was significantly greater than in control Border terriers at 0.41 (0.07 to 1.14). Median cholecystokinin concentration in Border terriers with gall bladder mucocoeles was 13 pg/mL (6 to 45 pg/mL), which was significantly lower than in control Border terriers at 103 pg/mL (9 to 397 pg/mL). There was no difference in the anti-gliadin IgG between these groups. There was no difference observed in the non-Border terriers with gall bladder mucocoeles with either of the other groups.

CLINICAL SIGNIFICANCE

Reduced cholecystokinin and increased transglutaminase-2-IgA autoantibodies was detected in Border terriers with gall bladder mucocoeles; which is in part homologous to gall bladder disease identified in human coeliac disease. The results suggest an immunological disease with impaired cholecystokinin release may be affecting gall bladder motility and possibly contributing to mucocoele formation in Border terriers.

CT attenuation values and mineral distribution can be used to differentiate dogs with and without gallbladder mucoceles

Gallbladder mucoceles are potentially fatal in dogs. Multiphase CT angiography was performed to evaluate the canine gallbladder in three conditions: no sludge, sludge occupying ≥25% of the lumen, and mucoceles. Twenty dogs with normal hepatobiliary bloodwork and no-to-minimal gallbladder sludge, 13 dogs with normal bloodwork and ≥25% sludge in the gallbladder lumen, and 18 dogs with histologically confirmed gallbladder mucoceles were enrolled in a prospective, observational diagnostic accuracy study. Three regions of interest (ROI) were stratified in the dorsal-ventral orientation and a single ROI was measured within the hepatic parenchyma. Mean attenuation and presence of mineral were recorded. Average Hounsfield units (HU) were recorded for precontrast, arterial, portovenous, and late venous phases. The overall median HU value for mucoceles was significantly higher than gallbladders without sludge and with sludge; precontrast median overall attenuation was 49.3, 35.8, and 39.7 HU, respectively (P < .000004). Mineral was seen in four (20%) dogs with no sludge, seven (56%) dogs with sludge, and nine (50%) dogs with mucoceles. Mineral in the dogs with mucoceles was located within the central aspect of the gallbladder lumen in 67% of mucoceles; this mineral distribution was not seen in any dog without a mucocele. Computed tomography can differentiate a subset of gallbladder mucoceles from dogs with and without gallbladder sludge, especially in the precontrast series. An HU value of 48.6 is 52% sensitive and 96% specific for a gallbladder mucocele. A hyperattenuating gallbladder on precontrast CT images and centrally distributed mineral can be a gallbladder mucocele.

Long-term survival of dogs treated for gallbladder mucocele by cholecystectomy, medical management, or both

BACKGROUND

Gallbladder mucoceles (GBM) typically are treated by cholecystectomy. Medical management rarely has been reported and medical and surgical management have not been compared.

HYPOTHESIS/OBJECTIVES

To compare survival of dogs treated for GBM by medical management or cholecystectomy or both.

ANIMALS

Eighty-nine client-owned dogs diagnosed with GBM that received cholecystectomy or medical treatment or both from 2011 to 2017.

METHODS

Potential cases were identified by searching the medical records database. Data collected included signalment, clinicopathologic results, treatments, and ultrasonographic images and reports. Dogs were grouped according to the treatment received (medical management, surgical treatment, or both) that was chosen at the discretion of the attending veterinarian. Survival analysis was performed and prognostic variables identified and compared between treatment groups.

RESULTS

Of dogs surviving at least 14 days after diagnosis, median survival times were 1802 (95% confidence interval [CI], 855-not reached) days, 1340 (95% CI, 444-1340) days, and 203 (95% CI, 18-525) days, for the surgical, medical, and medical then surgical treatment groups, respectively, and differed significantly (P < .0001). Gallbladder mucocele type (P = .05), serum alkaline phosphatase activity (P = .0001), and serum creatinine (P = .002) and phosphorus (P = .04) concentrations were associated with decreased survival across groups. Suspicion of biliary rupture on abdominal ultrasound (AUS) examination was correlated with increased survival in the surgical group (P = .02).

CONCLUSIONS AND CLINICAL IMPORTANCE

Cholecystectomy for the treatment of GBM results in the best long-term survival in dogs surviving the immediate postoperative period (14 days) compared to medical management. Although medical management is associated with shorter survival compared to surgical treatment, it is a reasonable alternative when surgery cannot be pursued.

Laparoscopic Cholecystectomy with Single Port Access System in 15 Dogs

OBJECTIVE

To evaluate the outcome of laparoscopic cholecystectomy performed with a single port access system (SPAS) in dogs.

STUDY DESIGN

Retrospective study.

ANIMALS

Fifteen client-owned dogs with nonobstructive gallbladder disease.

METHODS

Medical records were reviewed for signalment, clinical signs, diagnostic imaging, surgical findings, and outcome until suture removal.

RESULTS

The SPAS was placed 1 cm caudal to the umbilicus. The procedure was completed with the SPAS alone in two cases. An additional cannula was added in 12 cases. In the last 10 cases, the additional cannula was placed at the beginning of the procedure. Dissection began at the cystic duct in 11 dogs (73%). In three cases (20%), the SPAS procedure was converted to a laparotomy; two of these conversions were elective, and one was emergent. The risk of conversion was affected by the experience of the surgeon (odds ratio = 0.53; P = .0105), and the rate of conversion was reduced when a cannula was added at the beginning of the procedure (P = .022). Fourteen dogs were discharged from the hospital. One dog died after being discharged due to severe cholangiohepatitis, and another dog died due to leakage of a gastrostomy tube.

CONCLUSIONS

The use of SPAS for cholecystectomy in dogs has an acceptable outcome. The experience gained by the surgeon and the addition of a cannula reduced the risk of conversion.

CLINICAL RELEVANCE/IMPACT

Laparoscopic cholecystectomy can be performed with a SPAS. The placement of an additional cannula at the beginning of the procedure is highly recommended.

Effect of clinical signs, endocrinopathies, timing of surgery, hyperlipidemia, and hyperbilirubinemia on outcome in dogs with gallbladder mucocele

Gallbladder mucocele (GBM) is a common extra-hepatic biliary syndrome in dogs with death rates ranging from 7 to 45%. Therefore, the aim of this study was to identify the association of survival with variables that could be utilized to improve clinical decisions. A total of 1194 dogs with a gross and histopathological diagnosis of GBM were included from 41 veterinary referral hospitals in this retrospective study. Dogs with GBM that demonstrated abnormal clinical signs had significantly greater odds of death than subclinical dogs in a univariable analysis (OR, 4.2; 95% CI, 2.14-8.23; P<0.001). The multivariable model indicated that categorical variables including owner recognition of jaundice (OR, 2.12; 95% CI, 1.19-3.77; P=0.011), concurrent hyperadrenocorticism (OR 1.94; 95% CI, 1.08-3.47; P=0.026), and Pomeranian breed (OR, 2.46; 95% CI 1.10-5.50; P=0.029) were associated with increased odds of death, and vomiting was associated with decreased odds of death (OR, 0.48; 95% CI, 0.30-0.72; P=0.001). Continuous variables in the multivariable model, total serum/plasma bilirubin concentration (OR, 1.03; 95% CI, 1.01-1.04; P<0.001) and age (OR, 1.17; 95% CI, 1.08-1.26; P<0.001), were associated with increased odds of death. The clinical utility of total serum/plasma bilirubin concentration as a biomarker to predict death was poor with a sensitivity of 0.61 (95% CI, 0.54-0.69) and a specificity of 0.63 (95% CI, 0.59-0.66). This study identified several prognostic variables in dogs with GBM including total serum/plasma bilirubin concentration, age, clinical signs, concurrent hyperadrenocorticism, and the Pomeranian breed. The presence of hypothyroidism or diabetes mellitus did not impact outcome in this study.

Outcome of elective cholecystectomy for the treatment of gallbladder disease in dogs

OBJECTIVE To determine mortality rates for dogs undergoing cholecystectomy and variables associated with failure to survive to hospital discharge. DESIGN Retrospective cohort study. ANIMALS 70 dogs that underwent cholecystectomy for biliary tract disease at a companion animal referral hospital from 2009 through 2015. PROCEDURES Medical records of dogs were reviewed and data collected; dogs with biliary diversion surgery were excluded. Included dogs were grouped by whether cholecystectomy had been elective (ie, dogs with no or mild clinical signs, with no indication of biliary obstruction, or that initially underwent surgery for a different procedure) or nonelective (ie, dogs with icterus and questionable patency of the biliary system). Mortality rates (proportions of dogs that failed to survive to hospital discharge) were compared between various groups. RESULTS 45 (64%) dogs were included in the elective group and 25 (36%) in the nonelective group. Group mortality rates were 2% (1/45) and 20% (5/25), respectively, and differed significantly. Overall mortality rate was 9% (6/70). Serum albumin concentration was significantly lower and serum alanine aminotransferase activity and total bilirubin concentration were significantly higher in nonsurviving versus surviving dogs. Dogs with vomiting, signs of lethargy or anorexia, icterus, or azotemia were less likely to survive than dogs without these signs. CONCLUSIONS AND CLINICAL RELEVANCE Dogs that underwent elective cholecystectomy had a considerably lower mortality rate than previously reported. Elective cholecystectomy may be an appropriate recommendation for dogs with early signs of biliary disease to avoid the greater mortality rate associated with more advanced disease and nonelective cholecystectomy.

Investigation of adrenal and thyroid gland dysfunction in dogs with ultrasonographic diagnosis of gallbladder mucocele formation

Gallbladder mucocele formation is an emerging disease in dogs characterized by increased secretion of condensed granules of gel-forming mucin by the gallbladder epithelium and formation of an abnormally thick mucus that can culminate in obstruction of the bile duct or rupture of the gallbladder. The disease is associated with a high morbidity and mortality and its pathogenesis is unknown. Affected dogs have a significantly increased likelihood of concurrent diagnosis of hyperadrenocorticism, hypothyroidism, and hyperlipidemia. Whether these endocrinopathies represent coincidental primary disease processes that exacerbate gallbladder mucocele formation in predisposed dogs or reflect a concurrent disruption of endocrine and lipid metabolism is unclear. In this study, we investigated a hypothesis that dogs with gallbladder mucocele formation would have a high prevalence of occult and atypical abnormalities in adrenal cortical and thyroid gland function that would suggest the presence of endocrine disruption and provide deeper insight into disease pathogenesis. We performed a case-control study of dogs with and without ultrasonographic diagnosis of gallbladder mucocele formation and profiled adrenal cortical function using a quantitative mass spectrometry-based assay of serum adrenal-origin steroids before and after administration of synthetic cosyntropin. We simultaneously profiled serum thyroid hormone concentrations and evaluated iodine sufficiency by measurement of urine iodine:creatinine ratios (UICR). The studies were complemented by histological examination of archival thyroid tissue and measurements of thyroid gland organic iodine from dogs with gallbladder mucocele formation and control dogs. Dogs with gallbladder mucocele formation demonstrated an exaggerated cortisol response to adrenal stimulation with cosyntropin. A prevalence of 10% of dogs with gallbladder mucocele formation met laboratory-based criteria for suspect or definitive diagnosis of hyperadrenocorticism. A significantly greater number of dogs with gallbladder mucocele formation had basal serum dehydroepiandrosterone (DHEAS) increases compared to control dogs. A high percentage of dogs with gallbladder mucocele formation (26%) met laboratory-based criteria for diagnosis of hypothyroidism, but lacked detection of anti-thyroglobulin antibodies. Dogs with gallbladder mucocele formation had significantly higher UICRs than control dogs. Examination of thyroid tissue from an unrelated group of dogs with gallbladder mucocele formation did not demonstrate histological evidence of thyroiditis or significant differences in content of organic iodine. These findings suggest that dogs with gallbladder mucocele formation have a greater capacity for cortisol synthesis and pinpoint DHEAS elevations as a potential clue to the underlying pathogenesis of the disease. A high prevalence of thyroid dysfunction with absent evidence for autoimmune thyroiditis suggest a disrupted thyroid hormone metabolism in dogs with gallbladder mucocele formation although an influence of non-thyroidal illness cannot be excluded. High UICR in dogs with gallbladder mucocele formation is of undetermined significance, but of interest for further study.

Association of serum calprotectin (S100A8/A9) concentrations and idiopathic hyperlipidemia in Miniature Schnauzers

BACKGROUND

Idiopathic hyperlipidemia (IH) is a common condition in Miniature Schnauzers (MS). Studies in people have linked IH to low-grade inflammation, which plays an important role in the pathogenesis of IH complications. The role of inflammation in MS with IH is unknown.

OBJECTIVE

Evaluation of the inflammatory markers serum calprotectin and S100A12 in MS with IH and in response to dietary intervention for IH management.

ANIMALS

One-hundred fifty clinically healthy MS.

METHODS

Serum triglyceride, cholesterol, calprotectin, and S100A12 concentrations were measured before and after placing the dogs on an ultra-low fat diet.

RESULTS

Hypertriglyceridemia (HTGL, P < .001) and hypercholesterolemia (HCHOL, P = .01) were independently associated with increased serum calprotectin but not S100A12 concentrations. Compared to normolipidemic MS, serum calprotectin concentrations were significantly higher in MS with HTGL (P < .001) or combined hyperlipidemia (P = .02), but not those with isolated HCHOL (P = 1.0000). Presence (P = .005) and severity (P = .003) of HTGL and serum cholesterol concentrations (P = .04) decreased in MS with IH within 14-26 weeks after being placed on the ultra-low fat diet, but neither serum calprotectin nor S100A12 concentrations changed significantly with this dietary intervention.

CONCLUSIONS AND CLINICAL IMPORTANCE

Subclinical (low-grade) inflammation appears to be present in some MS with IH, and an ultra-low fat diet does not decrease serum concentrations of inflammatory proteins in those dogs. Whether this presumed inflammatory phenotype in MS with IH is associated with the development of IH complications (eg, insulin resistance) requires further research.

In vitro effect of 20% N-acetylcysteine on the viscosity of normal canine bile

OBJECTIVE To evaluate the in vitro effect of 20% N-acetylcysteine (NAC) on the viscosity of normal canine bile. ANIMALS Bile samples obtained from 10 adult dogs euthanized for reasons unrelated to biliary disease. PROCEDURES Each sample was centrifuged to remove particulates, then divided into 3 aliquots. One aliquot remained untreated (control). Each of the other aliquots was diluted 1:4 with 20% NAC or sterile water. The viscosity of all samples was measured with a rotational viscometer at 25°C. Viscosity of control samples was measured immediately after centrifugation and at 1 and 24 hours after treatment application to the diluted samples. Viscosity of diluted samples was measured at 1 and 24 hours after treatment application. RESULTS Mean viscosity differed significantly among the 3 groups at both 1 and 24 hours after treatment application. Relative to control samples, the addition of NAC and sterile water decreased the viscosity by approximately 3.35 mPa·s (95% confidence interval [CI], 1.58 to 5.12 mPa·s) and 2.74 mPa·s (95% CI, 1.33 to 4.14 mPa·s), respectively. Mean viscosity of the NAC-treated samples was approximately 0.61 mPa·s (95% CI, 0.21 to 1.01 mPa·s) less than that for the sterile water-treated samples. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that in vitro dilution of canine bile 1:4 with 20% NAC significantly decreased the viscosity of the resulting mixture. Further research is necessary to determine whether NAC is a safe and effective noninvasive treatment for dogs with persistent biliary sludge or gallbladder mucoceles.

Effect of prednisolone administration on gallbladder emptying rate and gallbladder bile composition in dogs

OBJECTIVE To investigate effects of prednisolone administration on gallbladder emptying rate and gallbladder bile composition in dogs. ANIMALS 6 healthy Beagles. PROCEDURES Prednisolone was administered (2 mg/kg, SC, once daily for 2 weeks) to each dog and tapered over 2 weeks. Gallbladder emptying rate and bile composition were evaluated before and after administration of prednisolone for 2 weeks as well as 1 week after cessation of prednisolone administration. RESULTS Gallbladder emptying rate decreased significantly after prednisolone administration (median, 27%; range, 0% to 38%), compared with rate before administration (median, 59%; range, 29% to 68%), but then increased 1 week after cessation of administration (median, 45%; range, 23% to 48%). Gallbladder bile mucin concentration decreased significantly after prednisolone administration (median, 8.8 mg/dL; range, 6.2 to 11.3 mg/dL), compared with concentration before administration (median, 13.1 mg/dL; range, 10.7 to 21.7 mg/dL), but then increased 1 week after cessation of administration (median, 14.3 mg/dL; range, 9.6 to 26.7 mg/dL). Gallbladder taurochenodeoxycholic acid concentration decreased significantly after prednisolone administration (8.1 mmol/L; range, 6.8 to 15.2 mmol/L), compared with concentration before administration (median, 27.2 mmol/L; range, 22.0 to 31.9 mmol/L), but then increased 1 week after cessation of administration (median, 26.4 mmol/L; range, 15.1 to 31.5 mmol/L). CONCLUSIONS AND CLINICAL RELEVANCE A lower gallbladder emptying rate caused by prednisolone administration may be involved in the pathogenesis of gallbladder disease in dogs. Further studies are required to determine the clinical importance of lower gallbladder bile mucin concentrations caused by glucocorticoid administration in the pathogenesis of gallbladder disease in dogs.

Short-term outcome of laparoscopic cholecystectomy for benign gall bladder diseases in 76 dogs

Laparoscopic cholecystectomy (LC) is widely accepted as the standard treatment for benign gall bladder diseases in humans because it has proven to be less invasive and safer than are traditional methods. However, the efficacy of LC in dogs remains unclear. The present study aimed to examine the short-term outcome of LC for benign gall bladder diseases in dogs. We enrolled 76 consecutive dogs that underwent LC for benign gall bladder diseases at our hospital between April 2008 and October 2016. Dogs with jaundice, gall bladder ruptures, abdominal effusion, or extrahepatic biliary obstruction were not excluded from the indication. Factors including age, body weight, sex, clinical sign, disease, operative time, conversion to open surgery, perioperative complications, and postoperative hospital stay were investigated. The median age of the dogs was 11 years, and the median body weight was 5.4 kg. Fifty percent of the dogs exhibited no symptoms at the initial visit. Preoperative elevation of total bilirubin levels was observed in 16 dogs (21%). LC was successfully completed in 71 dogs (93%); the median operative time was 124 min. Although gall bladder ruptures were observed in 2 (2.6%) dogs, the operations were completed successfully. Three dogs (4.1%) had to be converted to open cholecystectomy and 2 (2.6%) underwent reoperation. Two dogs (2.6%) died intraoperatively and 2 (2.6%) died postoperatively. LC was a feasible, safe, and appropriate procedure considering the current operative indications for benign gall bladder diseases in dogs.