Treatment of pancreatitis-associated extrahepatic biliary tract obstruction by choledochal stenting in seven cats

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.

Surgical Anatomy of the Gastrointestinal Tract in Cats

In cats, the gastrointestinal tract is one of the regions in which surgical procedures are most frequently performed by veterinary surgeons; therefore, knowledge of the surgical anatomy of the feline gastrointestinal tract is of high importance. The main surgical procedures performed include gastrotomy, gastrectomy, enterotomy, and enterectomy, as well as procedures in the liver and pancreas. There are also anatomical differences between dogs and cats, increasing the need for deep knowledge of the anatomy treated in the different surgical approaches. The aim of the present review is to describe in detail the anatomy of the gastrointestinal tract in cats highlighting the anatomical regions of significant importance in different surgical procedures.

Feline cholangitis/cholangiohepatitis complex - what have we learned?

Cholangitis/cholangiohepatitis complex in cats is commonly encountered in clinical practice worldwide. Diagnosis and management of cats with this complex is difficult because of the ambiguity of clinical signs, diagnostic test results and commonality of comorbid disorders. These impediments can delay disease identification and treatment, which can increase morbidity and mortality. ​In this narrative review, we aimed to provide a thorough review of the unique physioanatomic features of the biliary system as well as clinically relevant updates on cholangitis/cholangiohepatitis complex in cats.

Bacterial culture and immunohistochemical detection of bacteria and endotoxin in cats with suppurative cholangitis-cholangiohepatitis syndrome

OBJECTIVE

To characterize the frequency and type of bacterial infection by culture- and immunohistochemical (IHC)-based methods and determine the impact of infection on clinical features and survival time in cats with suppurative cholangitis-cholangiohepatitis syndrome (S-CCHS).

ANIMALS

168 client-owned cats with S-CCHS (cases).

PROCEDURES

Clinical features, bacterial culture results, culture-inoculate sources, and survival details were recorded. Cases were subcategorized by comorbidity (extrahepatic bile duct obstruction, cholelithiasis, cholecystitis, ductal plate malformation, biopsy-confirmed inflammatory bowel disease, and biopsy-confirmed pancreatitis) or treatment by cholecystectomy or cholecystoenterostomy. Culture results, bacterial isolates, Gram-stain characteristics, and IHC staining were compared among comorbidities. Lipoteichoic acid IHC staining detected gram-positive bacterial cell wall components, and toll-like receptor expression IHC reflected pathologic endotoxin (gram-negative bacteria) exposure.

RESULTS

Clinical features were similar among cases except for more frequent abdominal pain and lethargy in cats with positive culture results and pyrexia, abdominal pain, and hepatomegaly for cats with polymicrobial infections. Bacteria were cultured in 93 of 135 (69%) cats, with common isolates including Enterococcus spp and Escherichia coli. IHC staining was positive in 142 of 151 (94%) cats (lipoteichoic acid, 107/142 [75%]; toll-like receptor 4, 99/142 [70%]). With in-parallel interpretation of culture and IHC-based bacterial detection, 154 of 166 (93%) cats had bacterial infections (gram-positive, 118/154 [77%]; gram-negative, 111/154 [72%]; polymicrobial, 79/154 [51%]). Greater frequency of bacterial isolation occurred with combined tissue, bile, and crushed cholelith inoculates. Infection and gram-positive bacterial isolates were associated with significantly shorter long-term survival times.

CLINICAL RELEVANCE

S-CCHS was associated with bacterial infection, pathologic endotoxin exposure, and frequent polymicrobial infection in cats. Combined tissue inoculates improved culture detection of associated bacteria.

Clinical features, concurrent disorders, and survival time in cats with suppurative cholangitis-cholangiohepatitis syndrome

OBJECTIVE

To characterize clinical features, comorbidities, frequency of bacterial isolation, and survival time in cats with suppurative cholangitis-cholangiohepatitis syndrome (S-CCHS).

ANIMALS

168 client-owned cats with S-CCHS.

PROCEDURES

Data were prospectively (1980 to 2019) collected regarding clinical features, comorbidities, bacterial infection, illness duration, and treatments. Variables were evaluated for associations with survival time.

RESULTS

Median age of cats was 10.0 years, with no breed or sex predilection observed. Common clinical features included hyporexia (82%), hyperbilirubinemia (80%), lethargy (80%), vomiting (80%), jaundice (67%), weight loss (54%), and hypoalbuminemia (50%). Comorbidities included extrahepatic bile duct obstruction (53%), cholelithiasis (42%), cholecystitis (40%), and ductal plate malformation (44%) as well as biopsy-confirmed inflammatory bowel disease (60/68 [88%]) and pancreatitis (41/44 [93%]). Bacterial cultures were commonly positive (69%) despite prebiopsy antimicrobial administration in most cats. Of surgically confirmed choleliths, diagnostic imaging identified only 58%. Among 55 cats with "idiopathic pancreatitis," 28 (51%) were documented to have transiting choleliths, and 20 had pancreatic biopsies confirming pancreatitis. Cholelithiasis (with or without bile duct obstruction) and cholecystectomy were associated with survival advantages. Survival disadvantages were found for leukocytosis, ≥ 2-fold increased alkaline phosphatase, and hyperbilirubinemia. Cholecystoenterostomy had no survival impact. Cats with ductal plate malformations were significantly younger at diagnosis and death than other cats. Chronic treatments with antimicrobials, S-adenosylmethionine, and ursodeoxycholic acid were common postbiopsy.

CLINICAL RELEVANCE

S-CCHS in cats was associated with bacterial infection and various comorbidities and may be confused with pancreatitis. Surgically correctable morbidities (ie, cholecystitis, cholecystocholelithiasis) and cholecystectomy provided a significant survival advantage.

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.

Challenging diagnostic work-up of a massive fluid-filled structure in the cranial abdomen of a cat

A 9-year-old female, neutered European shorthair cat was presented with acute vomiting, obvious jaundice and painful enlargement of the abdomen. Icteric skin and mucous membranes in addition to severe bilirubinaemia (mainly direct bilirubin) and a large increase in liver enzyme activities were the main findings at the initial examination. Radio- and ultrasonographic evaluation revealed a massive fluid-filled structure caudal to the liver displacing abdominal organs, in particular the stomach. As this structure with a diameter of 8-10 cm occupied considerable space in the cranioventral abdomen, a detailed ultrasonographic examination of the liver and the gallbladder, and determination of the structure's association with a particular abdominal organ was initially impossible. Via ultrasound-assisted puncture under general anaesthesia 300 ml of an almost clear fluid could be aspirated. Cytological examination revealed a cyst content-like fluid with cell detritus.Further ultrasonographic and computed tomographic diagnostics followed by abdominal laparotomy finally enabled diagnosis of a cystic dilatation of the entire common bile duct and accumulation of white bile. Histopathological examination after euthanasia (requested by the owner) identified lymphoplasmacytic cholangitis and necrosis of the duodenal papilla. The massive dilatation of the common bile duct complicated its definite diagnosis by diagnostic imaging methods. It was most likely caused by a longer-standing obstruction of the bile flow by lymphoplasmacytic cholangitis with necrosis and granulation tissue formation in the area of the duodenal papilla. An interesting but initially misleading feature was the presence of white bile. The etiology of this extremely rare condition remains obscure but in the described case a manifestation of impaired hepatocyte function secondary to biliary stasis is suspected to be the cause.

Choledochal stenting for treatment of extrahepatic biliary obstruction in cats

Background

Limited information currently exists regarding the clinical progression and outcomes of cats that undergo choledochal stenting as a treatment for extrahepatic biliary obstruction (EHBO).

Hypothesis/Objectives

Describe clinical characteristics, indications for choledochal stent placement, procedure, and outcomes in a cohort of cats undergoing choledochal stenting and evaluate risk factors associated with survival as well as recurrence of EHBO in affected cats.

Animals

Twenty‐three client‐owned cats undergoing choledochal stent placement.

Methods

Retrospective study. Medical records from 6 academic institutions were reviewed, and data were extracted and analyzed statistically.

Results

Median age of cats was 10.1 years (range, 2‐16), and all cats had at least 2 clinical signs. Most common clinical signs were vomiting in 20/22 (90.9%), inappetence in 19/22 (86.4%), and lethargy in 19/23 (82.6%). Procedural complications were uncommon and rarely related to the stenting procedure. Clinical signs improved postoperatively in 15/20 (75.0%) cats and serum total bilirubin concentration decreased postoperatively in 13/19 (68.4%) cats. Eighteen (78.3%) cats survived to discharge. Recurrence of EHBO was documented in 7/18 (38.9%) cats that survived to discharge. Cholelithiasis was associated with recurrence of EHBO. Median survival time for cats that survived to discharge was 931 days (range, 19‐3034). Absence of peritoneal effusion was associated with survival to discharge.

Conclusions and Clinical Importance

Choledochal stenting was an effective treatment modality in cats with EHBO with few procedural complications and potential for prolonged survival, but substantial risk for recurrence of EHBO was identified.

Surgical Management of Feline Extrahepatic Biliary Tract Diseases

Extrahepatic biliary obstruction occurs infrequently in cats. Pathophysiology of biliary obstruction is characterized by cholestasis, obstruction, inflammation, and exudation. Clinical signs and laboratory examination findings are nonspecific. Ultrasonographic examination of the biliary tract aids significantly in diagnosis. The aims of feline biliary surgery are to determine the underlying cause and extent of the obstruction, restore bile flow to the gastrointestinal tract, and prevent bile leakage and subsequent peritonitis. Surgical techniques to restore bile flow and decompress the biliary distension include cholecystostomy tube placement and choledochal stenting, cholecystectomy, choledochotomy, and biliary diversion procedures. Surgical management of extrahepatic biliary obstruction carries a fair to guarded prognosis. Cats undergoing biliary diversion procedures have poorer outcomes than those undergoing nondiversion procedures. Cats with neoplastic involvement have significantly shorter lives than those with inflammatory involvement.

Percutaneous transhepatic cholecystostomy drainage in a dog with extrahepatic biliary obstruction secondary to pancreatitis

CASE DESCRIPTION

An 8-year-old 36.3-kg (79.9-lb) spayed female Rottweiler was evaluated because of anorexia and vomiting.

CLINICAL FINDINGS

Extrahepatic biliary obstruction (EHBO) secondary to pancreatitis was suspected on the basis of results from serum biochemical analyses, CT, and cytologic examination.

TREATMENT AND OUTCOME

Only marginal improvement was observed after 24 hours of traditional medical management; therefore, novel continual biliary drainage was achieved with ultrasonographically and fluoroscopically guided placement of a percutaneous transhepatic cholecystostomy drainage (PCD) catheter. Within 24 hours after PCD catheter placement, the dog was eating regularly, had increased intestinal peristaltic sounds on abdominal auscultation, no longer required nasogastric tube feeding, and had decreased serum total bilirubin concentration (7.7 mg/dL, compared with 23.1 mg/dL preoperatively). Bile recycling was performed by administering the drained bile back to the patient through a nasogastric tube. The PCD remained in place for 5 weeks and was successfully removed after follow-up cholangiography confirmed bile duct patency.

CLINICAL RELEVANCE

Transhepatic PCD catheter placement provided fast resolution of EHBO secondary to pancreatitis in the dog of the present report. We believe that this minimally invasive, interventional procedure has the potential to decrease morbidity and death in select patients, compared with traditional surgical options, and that additional research is warranted regarding clinical use, safety, and long-term results of this procedure in veterinary patients, particularly those that have transient causes of EHBO, are too unstable to undergo more invasive biliary diversion techniques, or have biliary diseases that could benefit from palliation alone.

Common bile duct obstruction caused by a helminth in a cat in the UK: ultrasonographic findings, histopathology and outcome

Case summary

An 11-year-old neutered female domestic shorthair cat presented to our hospital with a 5-day history of vomiting, lethargy, anorexia and hyperbilirubinaemia, despite intravenous fluid therapy, gastroprotectants and antibiotic treatment. An abdominal ultrasound revealed a markedly distended common bile duct (diameter 6.2 mm). The cystic duct and intrahepatic bile ducts were also dilated. A linear structure formed by two parallel hyperechoic lines was identified in the common bile duct and could be traced to the duodenal papilla. The cat underwent laparotomy for surgical decompression of the biliary tree. A tubular, brown-coloured structure was retrieved from the common bile duct. Histological examination was consistent with a degenerate helminth. The cat recovered uneventfully from the surgery and its demeanour and appetite improved rapidly over the following days. Liver and gallbladder wall histopathology was consistent with bacterial cholangitis and cholecystitis. Escherichia coli was cultured from both bile and liver parenchyma.

Relevance and novel information

To our knowledge, this is the first reported case of extrahepatic biliary duct obstruction caused by a helminth in a cat in the UK. We hypothesised that the obstruction had been caused by the aberrant migration of an intestinal nematode that became lodged in the duodenal papilla. Ultrasound allowed prompt diagnosis and guided the treatment decision.

Ultrasonographic evaluation of cholecystoduodenostomy sites in six cats

CASE SERIES SUMMARY

This case series describes the postoperative ultrasonographic findings in six cats that underwent a cholecystoduodenostomy as treatment for extrahepatic biliary obstruction. The surgery site was identified in all six cats, most often within the right cranial abdomen as a thick-walled gall bladder, with a broad-based connection to the descending duodenum. Postoperatively, the biliary tree often remained distended, similar to its preoperative appearance. Recurrent extrahepatic biliary obstruction was suspected in three cats with worsening hyperbilirubinemia. Common bile duct distension was progressive in one of these cats and unchanged in another, but improved in the third. Intrahepatic bile duct distension resolved in one cat following surgery but reappeared with suspected recurrent biliary obstruction. In two cats, progressive echogenic biliary contents were associated with locally aggressive cholangiocarcinoma. Our findings suggest that in cats with cholecystoduodenostomy and progressive increases in hyperbilirubinemia following surgery, progressive or recurrent biliary distension and/or progressive echogenic biliary contents should prompt further investigation.

RELEVANCE AND NOVEL INFORMATION

Biliary diversion surgery in cats is associated with high morbidity and mortality. The ultrasonographic appearance of a postoperative cholecystoduodenostomy site has not been described, making differentiation of the expected appearance from postoperative abnormalities difficult. The goal of this study was to determine the expected ultrasonographic appearance, in order to assist in managing cats with recurrent, persistent or worsening clinical signs and biochemical abnormalities following surgery.

Feline abdominal ultrasonography: what's normal? what's abnormal? The biliary tree

PRACTICAL RELEVANCE

Abdominal ultrasound plays a vital role in the diagnostic work-up of many cats presenting to general and specialist practitioners. The biliary tree encompasses the liver, gall bladder and bile ducts, although only diseases affecting the latter two are discussed here. Diseases of the bile ducts and gall bladder are more common than those of the liver parenchyma and ultrasound plays an important role in their diagnosis.

CLINICAL CHALLENGES

Despite ultrasonography being a commonly used modality, many practitioners are not comfortable performing an ultrasound examination or interpreting the resulting images. Even differentiating between normal variation and pathological changes can be challenging for all but the most experienced. In addition, a lack of pathological change does not necessarily rule out disease; for example, absence of gall bladder and/or extrahepatic biliary distension is not sufficient to exclude the possibility of biliary obstruction, and in many cases of cholangitis the liver and biliary tree are unremarkable on ultrasound examination.

EQUIPMENT

Ultrasound facilities are readily available to most practitioners, although use of ultrasonography as a diagnostic tool is highly dependent on operator experience.

AIM

This review, part of an occasional series on feline abdominal ultrasonography, discusses the appearance of the normal and diseased biliary system. It is aimed at general practitioners who wish to improve their knowledge and confidence in feline abdominal ultrasound and is accompanied by high-resolution images. Percutaneous ultrasound-guided cholecystocentesis is also covered. Ultrasound examination of the liver was discussed in an article published in January 2019 and an upcoming article will cover hepatic vascular anomalies.

EVIDENCE BASE

Information provided in this article is drawn from the published literature and the author's own clinical experience.

Mechanisms, causes, investigation and management of vomiting disorders in cats: a literature review

Vomiting is a common presenting complaint in feline practice. This article differs from previous reviews in that it is an evidence-based review of the mechanisms, causes, investigation and management of vomiting in the domestic cat. Published evidence was reviewed, and then used to make recommendations for clinical assessment, diagnosis, antiemetic drug treatment, dietary management and monitoring of cats presenting with vomiting. The strength of the evidence on which recommendations are made (and areas where evidence is lacking for cats) has been highlighted throughout.

Pancreatic rupture in four cats with high-rise syndrome

Pancreatic trauma and rupture are rare after feline high-rise syndrome; however, should it happen, pancreatic enzymes will leak into the abdominal cavity and may cause pancreatic autodigestion and fatty tissue saponification. If not diagnosed and treated, it can ultimately lead to multiorgan failure and death. In this case series, 700 records of high-rise syndrome cats that presented between April 2001 and May 2006 were analysed, and four cats with pancreatic rupture were identified. Clinical signs, diagnosis using ultrasonography and lipase activity in blood and abdominal effusion, and treatment modalities are reported. Three cats underwent surgical abdominal exploration, one cat was euthanased. Rupture of the left pancreatic limb was confirmed in all cases. Two of the operated cats survived to date. High-rise syndrome can lead to abdominal trauma, including pancreatic rupture. A prompt diagnosis and surgical treatment should be considered.

Complications of the extrahepatic biliary surgery in companion animals

Surgery of the biliary tract is demanding and is associated with several potentially life-threatening complications. Veterinarians face challenges in obtaining accurate diagnosis of biliary disease, surgical decision-making, surgical hemostasis and bile peritonitis. Intensive perioperative monitoring is required to achieve early recognition of common postoperative complications. Proper treatment and ideally, avoidance of surgical complications can be achieved by gaining a clear understanding physiology, anatomy, and the indications for hepatobiliary surgery.

Diseases of the gallbladder and biliary tree. Vet Clin North Am Small Anim Pract. 2009;39:543-598. [PMID: 19524793 DOI: 10.1016/j.cvsm.2009.01.004]

Most disorders of the biliary system are associated with increased activity of parenchymal transaminases (alanine aminotransferase, aspartate aminotransferase) and cholestatic enzymes (alkaline phosphatase and gamma glutamyl transferase) with or without hyperbilirubinemia or jaundice. While parenchymal liver disease is most common in the dog, inflammatory disorders involving the small- and medium-sized bile ducts and zone 1 (periportal) hepatocytes predominate in the cat. Historically, the incidence of disorders restricted to the gallbladder is low in both species; however, with routine diagnostic use of abdominal ultrasonography, the incidence of gallbladder mucoceles and cholelithiasis has increased. Extrahepatic bile duct obstruction is a well-recognized syndrome because of its association with pancreatitis and obvious jaundice. Less common disorders of the biliary system include a cadre of diverse conditions, including necroinflammatory processes, cholelithiasis, malformations, neoplasia, and an emerging syndrome of gallblader dysmotility.