Gastrointestinal small-cell lymphoma with gall bladder involvement in a cat

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.

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.

Feline biliary tree and gallbladder disease: Aetiology, diagnosis and treatment

Practical relevance Diseases of the biliary tree and gallbladder are more common in cats than diseases of the liver parenchyma. The parenchyma is usually affected secondarily to systemic illnesses, while the biliary system is the prime target for infectious agents (eg, bacteria and flukes) and non-infectious conditions (eg, neoplasia and cysts). Clinical approaches Cats with biliary disease are evaluated because of common feline clinical signs such as anorexia, nausea, vomiting and lethargy. Icterus may or may not be obvious. Biopsies for histological evaluation, and bile aspirates for culture and cytological evaluation are helpful diagnostically. Antibiotics and immunosuppressive drugs have been used successfully. Hepatosupportive drugs may help in liquefying thick bile and protecting hepatic tissue from damage. Ultrasound is a noninvasive diagnostic tool that may help in identifying dilated bile ducts, liver cysts and choleliths. It is also used to guide percutaneous bile aspiration. Audience This review, written for all veterinarians who treat cats, describes the various conditions that can affect the feline biliary tree and gallbladder. Treatment options are discussed, and brief summaries provided of surgical techniques and diagnostic approaches. Evidence base The veterinary literature pertaining to feline biliary disease is comprehensively reviewed. When appropriate, data on dogs and humans has been included to provide background information. Based on the available literature, more research into feline biliary diseases is needed.

Gallbladder lymphoma in a miniature dachshund

A 7-year-old, miniature dachshund was referred for examination and treatment of persistent anorexia, deep yellow-coloured urine and leucocytosis. The clinical sign of jaundice, results from a serum biochemistry profile and ultrasonographic images suggested a biliary tract obstruction. A cholecystectomy was performed to remove the obstruction. Histopathological assessment of the resected gallbladder and partial common bile duct indicated diffuse large B-cell lymphoma. Twelve days after the initial operation, a second procedure was performed due to bile leakage into the abdominal cavity. Chemotherapy was administered twice after the second operation but discontinued, because the dog showed adverse effects. The dog is still alive 24 months after the surgery. To the authors’ knowledge, this is the first description of canine gallbladder lymphoma.

Beyond H&E: integration of nucleic acid-based analyses into diagnostic pathology

Veterinary pathology of infectious, particularly viral, and neoplastic diseases has advanced significantly with the advent of newer molecular methodologies that can detect nucleic acid of infectious agents within microscopic lesions, differentiate neoplastic from nonneoplastic cells, or determine the suitability of a targeted therapy by detecting specific mutations in certain cancers. Polymerase chain reaction-based amplification of DNA or RNA and in situ hybridization are currently the most commonly used methods for nucleic acid detection. In contrast, the main methodology used for protein detection within microscopic lesions is immunohistochemistry. Other methods that allow for analysis of nucleic acids within a particular cell type or individual cells, such as laser capture microdissection, are also available in some laboratories. This review gives an overview of the factors that influence the accurate analysis of nucleic acids in formalin-fixed tissues, as well as of different approaches to detect such targets.