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

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.

Increased risk of gallbladder rupture and death in small-breed dogs with concurrent hypothyroidism or pancreatitis undergoing cholecystectomy for gallbladder mucoceles

The objectives of this multicenter, retrospective study were to: i) describe the incidence of gallbladder (GB) rupture in small-breed dogs affected by gallbladder mucoceles (GBM) and common endocrinopathies; and ii) determine if certain endocrinopathies were risk factors for GB rupture as they have been for the development of GBM. A total of 371 dogs were included in the study. Medical records from private specialty hospitals were reviewed for small-breed dogs undergoing cholecystectomy for GBM. Forty-seven of 193 dogs (24.4%) with endocrinopathies were diagnosed with GB rupture. Mortality due to GB rupture was 23.9%. Dogs with GB rupture were 3.2 times more likely to die than dogs without rupture (P < 0.001). Dogs with overall concurrent endocrinopathies, hypothyroidism, and pancreatitis were 2.5, 4.1, and 2.6 times (P = 0.001, 0.001, 0.002) more likely to develop a GB rupture and 2.6, 4.4, and 2.8 times (P = 0.008, 0.013, 0.011) more likely to die than dogs without concurrent endocrinopathies. Dogs with hyperadrenocorticism were not associated with a higher risk of GB rupture (P = 0.114) or death (P = 0.321). It was concluded that elective cholecystectomy should be considered in dogs with GBM and concurrent endocrinopathies, especially hypothyroidism and pancreatitis, to lower the risk of gallbladder rupture and death.

Clinical findings and prognostic factors for immediate survival in 33 dogs undergoing surgery for biliary peritonitis

OBJECTIVE

To report demographics, clinical signs, physical examination, diagnostic test results, surgical findings, and prognostic factors for in-hospital postoperative mortality following biliary peritonitis surgery in dogs.

STUDY DESIGN

Retrospective, multi-institutional cohort study.

ANIMALS

Thirty-three client-owned dogs.

METHODS

The medical records of dogs that underwent surgery for biliary peritonitis between 2015 and 2021 were reviewed. Dogs were included if they had a definitive diagnosis of biliary peritonitis and a surgery report. Information on demographics, clinical signs and duration, physical examination findings, laboratory and diagnostic imaging results, surgery, perioperative medical treatment, and complications for each patient was obtained. Statistical analyses were performed to identify risk factors that affected survival.

RESULTS

Cholecystectomy was the procedure most frequently performed (31/33, 94%). The overall mortality rate was 36% (12/33). Survival was affected negatively by hyperbilirubinemia (p = .049), administration of vasopressors (p = .002), renal dysfunction (p = .008), and number of postoperative complications (p = .005). A mortality rate of 50% was observed in dogs with a total bilirubin level greater than 60.5 μmol/L. There was no difference in mortality rate between septic and nonseptic biliary effusions.

CONCLUSION

New prognostic factors associated with in-hospital postoperative mortality in dogs treated surgically for biliary peritonitis were identified, while others that had been reported previously were confirmed. A preoperative bilirubin threshold value associated with a 50% mortality was identified.

CLINICAL SIGNIFICANCE

Additional information that could help to predict survival in dogs with biliary peritonitis has been provided. However, further research is warranted.

Magnetic Resonance Cholangiopancreatography for Cholangiopancreatic Duct Imaging in Dogs

Ultrasonography is often used to diagnose biliary diseases in dogs; however, it is difficult to delineate the entire bile and pancreatic ducts. Various imaging techniques for bile and pancreatic ducts have been attempted to overcome this problem. Magnetic resonance cholangiopancreatography (MRCP) is often used to evaluate the bile and pancreatic ducts in humans with obstructive jaundice, but very few reports exist on its usage in dogs. This study was designed as a prospective observational study to assess the feasibility and effectiveness of MRCP for visualizing the bile and pancreatic ducts in nondiseased dogs. Therefore, this study aimed to evaluate the visibility of the bile and pancreatic ducts through MRCP imaging using a 3.0 T-MRI system in dogs with no signs of hepatic, biliary, and pancreatic diseases. The detection rate for each anatomical structure was evaluated, with the highest observed in the gallbladder (100%), followed by the common bile duct (80%), cystic duct (70%), pancreatic ducts in the left and right lobe of the pancreas (70%), left and right hepatic ducts (60%), accessory pancreatic ducts (60%), and major pancreatic duct (40%). MRCP is a promising noninvasive imaging technique that can promptly and accurately visualize bile and pancreatic ducts in dogs without being influenced by the skill of the operator.

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.

Feasibility of open cholangioscopy with disposable flexible endoscopes

OBJECTIVE

To determine the feasibility of open cholangioscopy using disposable flexible endoscopes in canine cadavers and describe the surgical approach.

STUDY DESIGN

Ex vivo experimental cadaveric study.

SAMPLE POPULATION

Eight canine cadavers.

METHODS

Cadavers ranging from 5.8 to 43.8 kg underwent open transcholecystic cholangioscopy using a disposable flexible endoscope with a 3.8 mm outer diameter and 1.2 mm working channel and the surgical approach was described. The most distal anatomical region of the biliary tree towards the duodenal papilla that was visualized with the endoscope was recorded in each cadaver. A 2.7 mm rigid endoscope and a 1.9 mm flexible endoscope were also trialed and findings recorded. Endoscopic tools were trialed and their usage recorded.

RESULTS

The disposable flexible endoscope was feasible for visualization of the junction of the common bile duct, cystic duct, and hepatic ducts in all eight dogs. Cholangioscopy using a 2.7 mm rigid endoscope did not provide further distal visualization. The 1.9 mm flexible endoscope was able to traverse down to the level of the major duodenal papilla in a 43.8 kg cadaver. Use of certain endoscopic tools can be considered through the disposable flexible endoscope although fluid instillation was affected.

CONCLUSION

A 3.8 mm disposable flexible endoscope could be placed through an open transcholecystic approach to provide intraluminal endoscopic evaluation up to the level of the junction of the common bile duct, cystic duct, and hepatic ducts in dogs without cholecystic disease.

CLINICAL SIGNIFICANCE

Open transcholecystic cholangioscopy with a disposable flexible endoscope could provide a low-cost diagnostic and therapeutic tool in cases of obstructive biliary disease up to the level of the common bile duct.

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.

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.

Surgical Management Of Feline Biliary Tract Disease: Decision-making and techniques

PRACTICAL RELEVANCE

Diseases of the hepatobiliary system are not uncommon in first-opinion practice. The anatomy of the feline hepatobiliary tract differs from that of dogs and may predispose cats to inflammatory hepatobiliary disease. Case management can be challenging, and the prognosis is variable and dependent on the underlying disease process.

CLINICAL CHALLENGES

Biliary tract disease in the cat has non-specific clinical signs that overlap with those of diseases of other body systems. Diagnostic tests of the hepatobiliary system are widely available, but interpretation of results can be challenging. Deciding on medical or surgical management can also be challenging; for example, various degrees of cholestasis may be seen with different diseases and disease severities, and will influence the decision to manage the patient medically or surgically. Surgery is indicated in cases of bile peritonitis, severe cholestasis, focal neoplasia or disease that is refractory to medical management. Intensive perioperative and postoperative management, with 24 h hospitalisation facilities, is essential.

AUDIENCE

This review article is written for the small animal general/primary care practitioner, with an emphasis on decision-making in the surgical management of feline hepatobiliary disease.

EVIDENCE BASE

Evidence available in the published literature is reviewed and presented, and the inherent limitations are discussed.

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.

[Neuroendocrine carcinoma of the gallbladder as a rare cause for melena and hematemesis in dogs]

A 9-year-old male Malinois was presented for further workup of acute melena, hematemesis and chronic weight loss for a duration of one month. Clinically, the patient presented with a mildly reduced general condition. Blood tests revealed mild non-regenerative anemia as well as a mild elevation of alanine aminotransferase (ALT). Ultrasonography showed signs of an early mucocele. Treatment with gastroprotectants failed to lead to clinical improvement and the dog developed progressive anemia. Gastroduodenoscopy was unremarkable. Due to persistent clinical signs, exploratory laparotomy was performed. An ulcerated bleeding mass was detected at the gallbladder neck. Histopathological examination led to the diagnosis of a neuroendocrine carcinoma. There was no evidence of a mucocele on histopathology. Melena and hematemesis subsided postoperatively and 13 months after cholecystectomy, the dog remains without clinical signs. Neuroendocrine carcinomas of the gallbladder should be considered as a rare cause of melena and hematemesis in dogs.

Multi-phase MULTIDETECTOR-row computed tomographic features and laboratory findings in dogs with gallbladder rupture

Gallbladder rupture is a life-treating condition in dogs. In human medicine, multidetector-row computed tomography (MDCT) is considered the best modality for the diagnosis of gallbladder rupture. The aims of the study were to describe MDCT features of gallbladder rupture in dogs and to determine the CT findings and laboratory data that differ between dogs with ruptured biliary tree and dogs with biliary disease with no rupture. For this single-center, cross-sectional study were considered for inclusion dogs presented from May 2010 to September 2020, with surgical diagnosis of gallbladder rupture or integrity, who underwent MDCT examination and with CBC and biochemistry results available for review. Forty-seven dogs with different diseases of the biliary tract were included. Seventeen dogs with confirmed gallbladder rupture and 30 dogs with intact gallbladder were included. Multiple MDCT findings showed statistical significance in distinguish dogs with gallbladder rupture: irregular contours of the gallbladder (p < 0.0001), discontinuation of the gallbladder wall (p = 0.0005), adhesions with adjacent organs (p = 0.005), heterogeneous enhancement of the gallbladder wall (p = 0.01), pericholecystic effusion (p = 0.001) and pericholecystic peritonitis (p = 0.001). The presence of three or more of these findings was highly indicative for gallbladder rupture (AUC = 0.921). In this study, MDCT proved to be useful in differentiating dogs with gallbladder rupture from dogs with biliary disease without rupture.

Extradural anaesthesia-analgesia in dogs undergoing cholecystectomy: A single centre retrospective study

Objectives

To assess the effects of extradural anaesthesia-analgesia (EAA) in dogs undergoing cholecystectomy.

Materials and methods

Medical records of dogs undergoing cholecystectomy between 2011 and 2019 were retrieved and allocated to two groups depending if analgesia was provided systemically (group SA) or extradurally (EAA). Preoperative data, intraoperative antinociceptive medications, postoperative analgesia, perioperative complications, and food intake were compared.

Results

Overall 41 medical records were included in the study: 19 and 22 dogs were allocated to groups SA and EAA, respectively. In group EAA, an extradural catheter was placed preoperatively in 8 dogs; in the remaining, it was placed postoperatively but an extradural injection was performed preoperatively. The extradural catheter tip was between the 4th lumbar and the 10th thoracic vertebrae. Intraoperatively, nociception was more likely to occur in group SA [OR 55.42 (2.97–1,035.06)]. During the first 24 and 48 h postoperatively, more dogs in group SA required methadone [OR 24 (2.81–268.4) and OR 11.56 (2.37–45.06), respectively] and additional analgesic drugs [OR 25 (3.47–281.9) and OR 35.29 (1.86–668.2), respectively] compared to group EAA. Voluntary postoperative food intake was also significantly higher in group EAA.

Clinical significance

Compared to systemic analgesia, the use of extradural anaesthesia-analgesia reduced perioperative analgesic requirement and promoted postoperative food intake in dogs undergoing cholecystectomy.

Long-Term Outcome after Cholecystectomy without Common Bile Duct Catheterization and Flushing in Dogs

The aim of this study is to report outcomes of dogs undergoing cholecystectomy for gall bladder mucocele (GBM) without flushing and catheterization of the common bile duct (CBD). This is a retrospective multicentric study from three veterinary referral hospitals and included 82 dogs diagnosed with GBM. Medical records were reviewed for clinical and histopathological findings. Long-term outcome was assessed with an owner questionnaire. The common bile duct was considered normal (<4 mm), mildly dilated (5−6 mm) and moderately dilated (>7 mm) in 88%, 10% and 2.4% of dogs, respectively. Surgery was uncomplicated in 83% of dogs. Intraoperative complications were recorded in 21% of dogs, with hypotension being the most common, whereas postoperative complications were documented in 20% of dogs, with vomiting/regurgitation being the most common. Ninety-six percent of dogs that underwent cholecystectomy in this study survived to discharge. Follow-up ranged from 142 to 3930 days (median: 549 days). Eighty-five percent of dogs were alive at the time of follow-up. Dogs undergoing cholecystectomy for GBM without catheterization and flushing of the CBD have a favourable prognosis for recovery and quality of life.

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

Background

Objectives

Animals

Methods

Results

Conclusions and Clinical Importance

Ultrasonographic patterns, clinical findings, and prognostic variables in dogs from Asia with gallbladder mucocele

BACKGROUND

Gallbladder mucocele (GBM) is a common biliary disorder in dogs that can be categorized into 6 types, but the value of this classification scheme remains unknown. Cholecystectomy is associated with high death rates and warrants additional interrogation.

OBJECTIVES

Investigate the clinical value of ultrasonographic diagnosis of type of GBM and identify prognostic factors in dogs with GBM undergoing cholecystectomy.

ANIMALS

Two hundred sixteen dogs.

METHODS

Retrospective cohort study. Dogs with GBM diagnosed from 2014 to 2019 at 6 veterinary referral hospitals in Asia. Ultrasonogram images were reviewed and a GBM type (ie, types I-VI) assigned.

RESULTS

Dogs with GBM type V as compared to I (OR, 8.6; 95% CI, 2.6-27.8; P < .001) and III (OR, 10.0; 95% CI, 2.5-40.8; P = .001), and dogs with type VI compared to I (OR, 10.5; 95% CI, 1.8-61.2; P = .009) and III (OR, 12.3; 95% CI, 1.8-83.9; P = .01) were more likely to exhibit signs of biliary tract disease. Independent predictors of death after cholecystectomy included age (OR, 2.81; 95% CI, 1.41-5.59; P = .003) and intraoperative systolic blood pressure (SBP) nadir. There was an interaction between SBP nadir and gallbladder rupture; SBP nadir in dogs with (OR, 0.92; 95% CI, 0.89-0.94; P < .001) and without (OR, 0.88; 95% CI, 0.82-0.93; P < .001) gallbladder rupture.

CONCLUSION AND CLINICAL IMPORTANCE

Increasing developmental stage of GBM could be associated with an increased likelihood of biliary tract related clinical signs. Nadir SBP deserves further investigation as a prognostic or potentially modifiable variable, particularly in the presence of gallbladder rupture.

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.

Canine extrahepatic biliary disease: what have we learned?

Extrahepatic biliary disease in dogs is commonly encountered in clinical practice worldwide. Diseases in this segment of the biliary tract are diverse and can manifest with mild clinical signs or can be life-threatening. In the last decade there have been advances in diagnostic tests, imaging modalities and therapeutic interventions as well as the identification of novel prognostic variables that could improve outcomes in dogs with extrahepatic biliary disease. Therefore, the objective of this review was to summarise clinically relevant updates of extrahepatic biliary disease in dogs.

Cholecystectomy in 23 cats (2005-2021)

OBJECTIVE

To describe the clinical presentation, treatments, and long-term outcomes following cholecystectomy in cats.

STUDY DESIGN

Clinical retrospective study.

ANIMALS

Twenty-three client-owned cats.

METHODS

Medical records of all cats undergoing cholecystectomy between 2005 and 2021 at a single referral hospital were retrospectively reviewed. No cats were excluded. An owner questionnaire assessed long-term outcomes.

RESULTS

Vomiting, jaundice, and abdominal pain were the most common clinical signs; median duration of signs was 4 days (range 1-21). Cholelithiasis was the major indication for cholecystectomy followed by cholecystitis. Intraoperative hypotension and postoperative anemia were commonly encountered. Nine cats required a postoperative blood product transfusion. Cardiopulmonary arrest and death occurred in five cats. Eighteen cats (78.3%) survived to discharge. Long-term follow up (>60 days) was available for 16 cats at a median of 1003 days (range 81-4995). Fifteen cats survived over 6 months with eight cats (44.4%) surviving over 3 years. The most common short-term and long-term postoperative complication was vomiting. Owners assessed postoperative outcome as excellent in all cats and quality of life as excellent or good.

CONCLUSION

The most common indication for cholecystectomy was cholelithiasis. Perioperative complications were commonly encountered. Perioperative mortality rate was 21.7%. Long-term owner evaluation of clinical outcome was considered excellent.

CLINICAL SIGNIFICANCE

Cats undergoing cholecystectomy for non-neoplastic causes can have a favorable prognosis for recovery and quality of life. Concurrent extrahepatic biliary duct obstruction is not a contraindication for cholecystectomy provided that patency of the common bile duct is restored.

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.

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 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.

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.

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.