ULTRASONOGRAPHIC APPEARANCE AND CLINICAL FINDINGS IN 14 DOGS WITH GALLBLADDER MUCOCELE

Fourteen dogs with enlarged gallbladders and immobile stellate or finely striated bile patterns on ultrasound are described. Smaller breeds and older dogs were overrepresented, with 4/14 Cocker Spaniels. Most dogs presented for nonspecific clinical signs such as vomiting, anorexia and lethargy. Abdominal pain, icterus and hyperthermia were the most common findings on physical examination. All dogs except one had serum elevation of total bilirubin and/or alkaline phosphatase, alanine aminotransferase and gamma glutamyl transferase. All dogs were diagnosed with a gallbladder mucocele upon histologic and/or macroscopic evaluation. Ultrasonographically, mucoceles are characterized by the appearance of the stellate or finely striated bile patterns and differ from biliary sludge by the absence of gravity dependent bile movement. On ultrasound, gallbladder wall thickness and wall appearance were variable and nonspecific. The cystic or common bile duct were normal sized in 5 dogs although all 5 had evidence of biliary obstruction at surgery or necropsy. Loss of gallbladder wall integrity and/or gallbladder rupture were present in 50% of the dogs, all located in the fundus. Gallbladder wall discontinuity on ultrasound indicated rupture whereas neither bile patterns predicted the likelihood of gallbladder rupture. Pericholecystic hyperechoic fat or fluid were suggestive of but not diagnostic for a gallbladder rupture. Cholecystectomy appears to be an appropriate treatment for mucoceles, if not to treat a gallbladder rupture, at least in most dogs to prevent it since gallbladder wall necrosis was identified by histology in 9 of 10 dogs. Mucosal hyperplasia was present in all gallbladders examined histologically. Positive aerobic bacterial culture was obtained from bile in 6 of 9 dogs. Cholecystitis was diagnosed histologically in 5 dogs and 4 dogs had signs of gallbladder infection solely upon bacterial bile culture. Gallbladder infection was not present with all the mucoceles suggesting that biliary stasis and mucosal hyperplasia may be the primary factors involved in mucocele formation. Based on the results of our study, we suggest two alternate courses of action in the presence of a distended gallbladder with an immobile ultrasonographic stellate or finely striated bile pattern: a cholecystectomy when clinical or biochemical signs of hepatobiliary disease are present or a medical treatment (antibiotics and choleretics) and patient monitoring by follow-up ultrasound examinations when the patient does not have clinical or biochemical abnormalities. An aerobic bile culture should be obtained in all patients, by ultrasound-guided fine needle aspirate or at surgery.     

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.     

Gallbladder Mucocele: Variables Associated with Outcome and the Utility of Ultrasonography to Identify Gallbladder Rupture in 219 Dogs (2007–2016)

Background

Gallbladder mucocele (GBM) is an increasingly recognized extrahepatic biliary disease in dogs.

Objectives

To investigate cases of GBM and identify variables associated with survival and the sensitivity and specificity of ultrasonography to identify gallbladder rupture.

Animals

Two hundred and nineteen client‐owned dogs with GBM.

Methods

Multicenter, retrospective study of dogs with GBM, presented from January 2007 to November 2016 to 6 academic veterinary hospitals in the United States. Interrogation of hospital databases identified all cases with the inclusion criteria of a gross and histopathologic diagnosis of GBM after cholecystectomy and intraoperative bacteriologic cultures of at least 1 of the following: gallbladder wall, gallbladder contents, or abdominal effusion.

Results

Two hundred and nineteen dogs fulfilled the inclusion criteria. Dogs with GBM and gallbladder rupture with bile peritonitis at the time of surgery were 2.7 times more likely to die than dogs without gallbladder rupture and bile peritonitis (P = 0.001; 95% confidence interval [CI], 1.50–4.68; n = 41). No significant associations were identified between survival and positive bacteriologic cultures, antibiotic administration, or time (days) from ultrasonographic identification of GBM to the time of surgery. The sensitivity, specificity, positive, and negative likelihood ratios for ultrasonographic identification of gallbladder rupture were 56.1% (95% CI, 39.9–71.2), 91.7% (95% CI, 85.3–95.6), 6.74, and 0.44, respectively.

Conclusion and Clinical Importance

Dogs in our study with GBM and intraoperative evidence of gallbladder rupture and bile peritonitis had a significantly higher risk of death. Additionally, abdominal ultrasonography had low sensitivity for identification of gallbladder rupture.     

Decreased gallbladder emptying in dogs with biliary sludge or gallbladder mucocele

Biliary sludge in dogs is dismissed commonly as an incidental finding. On the other hand, gallbladder mucocele is reported increasingly in dogs and can lead to biliary obstruction or gallbladder rupture. Cholestasis is suspected to play a role in development of sludge and mucoceles, though there are no data in dogs to support this. We investigated gallbladder emptying, a key factor in biliary flow, in dogs with mobile sludge, immobile sludge, or gallbladder mucocele and in healthy controls. Gallbladder ejection fraction estimated by ultrasonography was used as the index of gallbladder emptying. The ejection fraction at 60 min after eating was significantly decreased in all three abnormal groups. Moreover, all dogs with sludge or a mucocele had gallbladder distension. These changes were the greatest in the mucocele group. Thus, biliary stasis occurs not only in dogs with gallbladder mucocele but also in dogs with biliary sludge. Cholestasis may play a role in the pathogenesis or progression of these diseases in dogs.     

CLINICAL AND ULTRASONOGRAPHIC CHARACTERISTICS OF SALIVARY MUCOCELES IN 13 DOGS

Salivary mucocele is one of the causes of submandibular swelling in dogs and is due to a collection of mucoid saliva that has leaked from a damaged salivary gland. The purpose of this case series report was to describe the clinical and ultrasonographic characteristics of confirmed salivary mucoceles in 13 dogs admitted to the Faculty of Veterinary Medicine at Cairo University. The final diagnosis of salivary mucocele was based on aspirate cytology for all dogs and additional surgical excision for seven dogs. For dogs admitted from 2 weeks to 1 month from the onset of clinical signs, the cervical mucocele appeared as a round echogenic structure with a large volume of central anechoic content. The wall was a clearly identified hyperechoic structure surrounding the gland. For dogs admitted between 1 to 2 months from the onset of clinical signs, the volume of anechoic material appeared less than that seen in the acute cases. The overall appearance of the salivary mucocele was heterogenous. For dogs admitted after 2 months from the onset of clinical signs, the salivary mucocele appeared grainy or mottled, with a heterogenous appearance and a further decrease in anechoic content. For one dog that presented after 3 months from the onset of clinical signs, the salivary mucocele was hard on palpation and appeared hyperechoic with distal acoustic shadowing. Findings from this study indicated that ultrasonographic characteristics of salivary mucoceles in dogs vary depending on the chronological stage of the disease.     

Contrast‐enhanced ultrasound complements two‐dimensional ultrasonography in diagnosing gallbladder diseases in dogs

Gall‐bladder diseases are common in dogs and two‐dimensional ultrasonography is a current standard method for diagnosis and treatment planning. However, findings from this modality can be nonspecific. The aim of this retrospective, case series study was to describe conventional and contrast‐enhanced ultrasound (using SonoVue^®) findings in a group of dogs with histologically confirmed gall bladder disease. A total of 65 dogs were included. Branchlike, heterogeneous, and homogeneous contrast enhancement of echogenic intraluminal mass‐forming lesions was a contrast‐enhanced ultrasound characteristic of polypoid lesions due to cystic mucosal hyperplasia of the gallbladder and/or tumor, which had different wash‐in and washout characteristics. In dogs with mobile or immobile biliary sludge or mucocele, the echogenic intraluminal masses remained unenhanced. A double rim mark or enhancement defect in the gallbladder wall was a characteristic of edema or necrosis/rupture of the wall, respectively. Conventional ultrasonography correctly identified biliary sludge or mucocele in 36/37 dogs, cholecystitis/edema in 44/47 dogs, necrosis/rupture in 19/25 dogs, and gallbladder neoplasia in three of three dogs with these pathologies. It falsely identified biliary sludge or mucocele in eight of 28 dogs, cholecystitis/edema in three of 15 dogs, necrosis/rupture in 13/37 dogs, and gall‐bladder neoplasia in 20/59 dogs that did not have these pathologies. Contrast‐enhanced ultrasound correctly identified cholecystitis/edema in 42/47 dogs, but falsely identified cholecystitis/edema in three of 18 dogs. It correctly identified necrosis/rupture, benign polypoid lesions, and gallbladder neoplasia in all dogs with no false‐positive results. Findings supported contrast‐enhanced ultrasound as a complement to conventional ultrasonography for dogs with suspected gallbladder pathologies such as edema, necrosis, and rupture.     

Ultrasonography and surgery of canine biliary diseases

Findings of hepatic and gallbladder ultrasonography were analyzed in 12 dogs with gallbladder and/or extrahepatic biliary tract obstruction and compared with the results of exploratory laparotomy. Hepatic ultrasonography demonstrated normal liver in 2 dogs and hepatic abnormalities in 10 animals. The following ultrasonographic diagnoses were established compared to surgical findings: gallbladder obstruction caused by bile sludge (correct/incorrect: 1/2, surgical diagnosis: choleliths in one case), gallbladder obstruction caused by neoplasm (0/1, surgical diagnosis: mucocele), gallbladder and extrahepatic biliary tract obstruction due to choleliths (3/3), extrahepatic biliary tract obstruction caused by pancreatic mass (1/1) and small intestinal volvulus (1/1). Bile peritonitis caused by gallbladder rupture (4/4) was correctly diagnosed by ultrasound, aided with ultrasonographically-guided abdominocentesis and peritoneal fluid analysis. Rupture of the gallbladder should be suspected in the presence of a small, echogenic gallbladder or in the absence of the organ together with free abdominal fluid during ultrasonography. Laparotomy was correctly indicated by ultrasonography in all cases. However, the direct cause of obstruction could not be determined in 2 of the 12 dogs by ultrasonography alone.     

Gallbladder mucocele in dogs: 30 cases (2000-2002)

OBJECTIVE: To determine long-term outcome of dogs with gallbladder mucocele. DESIGN: Retrospective study. ANIMALS: 30 dogs with gallbladder mucocele, including 23 that underwent cholecystectomy. PROCEDURE: Medical records were reviewed for signalment, history, and clinical, ultrasonographic, and surgical findings. Follow-up information was obtained for all dogs that survived the perioperative hospitalization period. RESULTS: 23 dogs had signs of systemic illness; 7 had no clinical signs. Median values for serum activities of alanine aminotransferase and alkaline phosphatase, serum total bilirubin concentration, and total WBC count were significantly higher among dogs with gallbladder rupture than among dogs without rupture. Sensitivity of sonography for detection of rupture was 85.7%. Overall perioperative mortality rate for dogs that underwent cholecystectomy was 21.7%; mortality rate was not significantly greater for dogs with rupture. Aerobic bacteria were isolated from the bile or gallbladder wall in 8.7% of dogs. All 18 dogs discharged from the hospital had complete resolution of clinical signs. In dogs that underwent in-hospital reexamination, serum liver enzyme activities were significantly decreased, compared with preoperative activities. Persistent increases in serum activities of 1 or more liver enzymes were detected in 9 of 12 dogs; 6 of 12 dogs had persistent abnormalities in hepatic echogenicity. Mean follow-up period was 13.9 months. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that cholecystectomy is an effective treatment for gallbladder mucocele. Although perioperative mortality rate is high, prognosis after discharge from the hospital is excellent. Rupture of the gallbladder warrants emergency surgical intervention but does not preclude a positive outcome.     

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

OBJECTIVE: To determine risk, clinical features, and treatment responses for gallbladder disorders in Shetland Sheepdogs. DESIGN: Retrospective case-control study. ANIMALS: 38 Shetland Sheepdogs with gallbladder disease. PROCEDURES: Medical records were reviewed for signalment, history, physical findings, laboratory results, imaging features, coexistent illnesses, histologic findings, treatments, and survival rates. RESULTS: Mature dogs with gastrointestinal signs were predisposed (odds ratio, 7.2) to gallbladder disorders. Gallbladder mucocele was confirmed in 25 dogs. Concurrent problems included pancreatitis, hyperlipidemia, corticosteroid excess, hypothyroidism, protein-losing nephropathy, diabetes mellitus, cholelithiasis, and gallbladder dysmotility. Mortality rate was 68% with and 32% without bile peritonitis. Nonsurvivors had high WBC and neutrophil count and low potassium concentration. Although preprandial hypercholesterolemia, hypertriglyceridemia, and high serum liver enzyme activities were common, gallbladder disease was serendipitously discovered in 11 of 38 dogs. Histologic examination (n=20 dogs) revealed gallbladder cystic mucosal hyperplasia in 20 dogs, cholecystitis in 16, periportal hepatitis in 9, and vacuolar hepatopathy in 7. Surgery included cholecystectomy (n=17) and cholecystoenterostomy (4). In 1 hyperlipidemic dog without clinical signs, gallbladder mucocele resolved 6 months after beginning use of a fat-restricted diet and ursodeoxycholic acid. CONCLUSIONS AND CLINICAL RELEVANCE: Shetland Sheepdogs are predisposed to gallbladder disorders, with mucoceles and concurrent dyslipidemia or dysmotility in many affected dogs. Most dogs were without clinical signs during mucocele development. Low survival rate after cholecystectomy in clinically affected dogs suggested that preemptive surgical interventions may be a more appropriate treatment strategy.     

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

BackgroundGallbladder 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.ObjectivesInvestigate the clinical value of ultrasonographic diagnosis of type of GBM and identify prognostic factors in dogs with GBM undergoing cholecystectomy.AnimalsTwo hundred sixteen dogs.MethodsRetrospective 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.ResultsDogs 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 ImportanceIncreasing 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.     

Surgical management of gallbladder mucoceles in dogs: 22 cases (1999-2003)

OBJECTIVES: To describe preoperative, surgical, and postoperative findings and determine prognostic indicators and treatment recommendations in dogs treated surgically for gallbladder mucocele. DESIGN: Retrospective study. ANIMALS: 22 client-owned dogs. PROCEDURES: Medical records of dogs with gallbladder mucoceles that were treated surgically were reviewed. History, clinical signs, results of selected clinicopathologic analyses and abdominal ultrasonography, surgical procedure performed, results of histologic examination of a liver biopsy specimen, and survival time were recorded. Follow-up information was obtained via telephone interview with owners and referring veterinarians. RESULTS: Dogs were 7 to 15 years of age and had non-specific clinical signs (vomiting, anorexia, and lethargy). Physical examination findings included icterus, signs of depression, and signs of discomfort on palpation of the abdomen. Sixteen dogs had a definitive diagnosis and 6 dogs were strongly suspected of having a gallbladder mucocele on the basis of results of abdominal ultrasonography. Fifteen dogs survived after surgery; 3 of these dogs had bile-induced peritonitis, and 4 had pancreatitis. One dog was euthanatized as a result of severe pancreatitis, and 1 was euthanatized because of acute renal failure; 5 dogs died as a result of pancreatitis, cholecystitis, or bile-induced peritonitis. Hepatic abnormalities were detected histologically in all dogs. CONCLUSIONS AND CLINICAL RELEVANCE: No predictors of survival were identified. No associations between outcome of surgical treatment (survival vs nonsurvival) and preoperative findings, biliary rupture, surgical procedure performed, results of histologic examination of the liver, or development of pancreatitis were found. Cholecystoduodenostomy and cholecystectomy appear to be acceptable treatments for gallbladder mucocele.     

Pharyngeal mucoceles in dogs: 14 cases

This report describes the clinical features of a series of dogs with pharyngeal salivary mucoceles. A retrospective study of 14 dogs with pharyngeal mucocele was performed. Medical records from 1983 to 2003 were reviewed for information regarding signalment, clinical signs, diagnosis, surgical procedures, and short-term and long-term outcome. Miniature and toy poodles were common breeds in the study population, and 79% of the dogs were male. The most common presenting sign was dyspnea (50%). Diagnosis was by fine-needle aspirate, which revealed a mucoid substance in 93% of dogs. Histopathology of the excised salivary glands revealed lymphoplasmacytic inflammation in all dogs that had histopathology performed. Forty-three percent of the dogs had a cervical mucocele on the same side as the pharyngeal mucocele. Surgical therapy was performed in 13 dogs, which consisted of excision of the mandibular and sublingual salivary glands, excision of the mucocele, or marsupulization of the mucocele. Only two dogs had recurrence of the pharyngeal mucocele. In this study, pharyngeal mucoceles occurred in predominantly small dogs that frequently presented with respiratory signs. Surgical treatment was successful in most dogs.     

ULTRASONOGRAPHIC ANATOMY OF THE NORMAL CANINE SPINAL CORD AND CORRELATION WITH HISTOPATHOLOGY AFTER INDUCED SPINAL CORD TRAUMA

Prior to trauma, intraoperative ultrasound of the spinal canal in 31 normal dogs was performed through a hemilaminectomy in the left pedicle of L2. A ventral compressive model of spinal cord injury was performed as part of a clinical drug trial. Maximum ultrasonographic spinal cord diameter ranged from 4.9–7.2 mm (5.7 × 0.6). Significant positive correlation (p = 0.023, r = 0.49) was found between age and spinal cord diameter. The dura mater was a separate, well-defined, echogenic horizontal line in 28 (90%) dogs, dorsally, and in 29 (94%) dogs, ventrally. Cerebrospinal fluid was anechoic. Eighteen (58%) dogs had a well-defined anechoic dorsal subarachnoid space, whereas 22 (71%) had a well-defined ventral space. Pia mater was thin but strongly echogenic and covered spinal cord. Central canal was a double hyperechoic line in 17 (55%) dogs and a single-line in 14 (45%) dogs. A difference in the ultrasonographic appearance between gray and white matter was not seen. Epidural fat and connective tissue was a lobular echogenic material in the ventral epidural space. The periosteal-vertebral body interface was seen as a bright curvilinear echo with distal acoustic shadowing. Spinal cord parenchyma could be classified subjectively into four groups based upon ultrasonographic appearance. Spinal cord parenchyma had a uniform hypoechogenicity in 8 (27%) dogs (Group 1), subtle low level echoes in 7 (23%) dogs (Group 2), multiple clusters of defined echogenic foci in 12 (37%) dogs (Group 3), and multiple sharply-defined linear echoes in 4 (13%) dogs (Group 4). There was a significant relationship between pre-trauma ultrasonographic appearance of the spinal cord and histopathology 21 days after trauma. One (13%) dog in Group 1, 4 (57%) dogs in Group 2,10 (91%) dogs in Group 3, and 3 (75%) dogs in Group 4 had malacia on histological evaluation. Therefore, dogs with echogenic spinal cords or linear echoes within cord parenchyma were significantly more likely to develop malacia rather than Wallerian degeneration after induced spinal cord trauma (p = 0.002). Spinal cord echogenicity may indicate vascularity in a segment of spinal cord and might be prognostic following spinal cord trauma. No complications were found related to intraoperative ultrasound. Hematoma or fibrous tissue formation appeared to impede percutaneous ultrasound of the spinal cord in dogs re-evaluated forty-eight hours and one week after surgery.     

Effects of iatrogenic hypercortisolism on gallbladder sludge formation and biochemical bile constituents in dogs

An association between gallbladder mucoceles and hypercortisolism (HC) was recently described in dogs. Because the formation of a mucocele from clear bile without the transitional formation of microprecipitates appears unlikely, the aim of this study was to investigate the effects of iatrogenic HC on sludge formation and changes in the biochemical composition of bile. Bile samples from 6 dogs obtained by percutaneous ultrasound-guided cholecystocentesis before (day 0), during (days 28, 56, and 84), and after (days 28p, 56p, and 84p) oral administration of hydrocortisone (8 mg/kg every 12 h) were analysed for calcium, cholesterol and bilirubin concentrations and pH. In addition the gallbladder was examined ultrasonographically for sludge. Six dogs receiving a placebo served as controls. Although gallbladder sludge was observed in all treated dogs at day 56, it was also noted in 50% of control dogs, and no significant differences were seen between groups at any sampling time. Bilirubin and cholesterol concentrations decreased significantly and reversibly during treatment, and calcium concentration showed a similar trend. Bile pH was consistently slightly alkaline during iatrogenic HC, whereas it was slightly acidic in control animals. A 3-month period of iatrogenic HC does not lead to ultrasonographically detectable gallbladder sludge or to an increase in bile constituents that are commonly implicated in sludge formation in humans.     

Factors affecting survival in 516 dogs that underwent cholecystectomy for the treatment of gallbladder mucocele

Gallbladder mucocele (GBM) is a commonly diagnosed disease process in dogs that is associated with high morbidity and mortality if not recognized and appropriately managed. Although the exact mechanism of this disease process is not completely understood, previous studies in smaller populations of dogs have identified multiple factors that predispose to the development of GBM and affect survival. The purpose of this cross-sectional, retrospective study was to evaluate the effects of age, breed category, sex, preoperative antibiotic administration, gallbladder rupture, and a positive biliary culture in dogs that had a cholecystectomy performed for the treatment of GBM. The age (median: 11 years) and percentage of dogs that died within 14 days of cholecystectomy (16.7%) are similar to what have been reported in other studies. Gallbladder rupture and a positive biliary culture occurred in 20.4% and 12.5% of dogs, respectively. Dogs with a gallbladder rupture and positive biliary culture were 2.74 and 3.10 times more likely to die within 14 days of cholecystectomy, respectively. This contradicts a recent study that failed to find a significant association between survival and biliary culture result. Interestingly, younger age was associated with an increased occurrence of gallbladder rupture in that population. Because of the potential effect of gallbladder rupture and a biliary tract infection, abdominal imaging, biliary culture, and empirical preoperative antimicrobial therapy are recommended in dogs undergoing cholecystectomy for the treatment of GBM.     

Nonsurgical resolution of gallbladder mucocele in two dogs

CASE DESCRIPTION: A gallbladder mucocele was diagnosed in 2 dogs. In both dogs, the mucocele resolved with medical treatment but without the need for surgical intervention. CLINICAL FINDINGS: A 12-year-old spayed female Miniature Schnauzer had a history of signs of gastrointestinal tract disease and high serum liver enzyme activities. Gallbladder mucocele and hypothyroidism were diagnosed. A 6-year-old neutered mixed-breed dog had chronic intermittent diarrhea and recurrent otitis; gallbladder mucocele and hypothyroidism were diagnosed. TREATMENT AND OUTCOME: The first dog was treated with S-adenosyl-methionine, omega-3 fatty acids, famotidine, ursodiol, and levothyroxine. Substantial improvement in the gastrointestinal tract condition and complete resolution of the gallbladder mucocele within 3 months were evident, but the dog was not available for further follow-up monitoring. The second dog was treated with fenbendazole, ursodiol, and levothyroxine and fed a hypoallergenic diet. One month after evaluation, abdominal ultrasonography revealed that the gallbladder mucocele was resolving, and treatment was continued. Ultrasonographic evaluation 2 and 4 months later revealed complete resolution of the mucocele. CLINICAL RELEVANCE: Review of the clinical course of 2 dogs in which there was nonsurgical resolution of gallbladder mucocele revealed that surgery is not necessary in all dogs with gallbladder mucocele. Hypothyroidism may have resulted in delayed gallbladder emptying, and its role in the pathogenesis of gallbladder mucocele merits investigation. Despite this information, until further prospective trials with a control group and standardized treatments and follow-up monitoring can be performed, the authors recommend surgical intervention for treatment of dogs with gallbladder mucocele.     

Long-term survival and risk factors associated with biliary surgery in dogs: 34 cases (1994-2004)

OBJECTIVE: To determine factors associated with long-term survival after biliary surgery in dogs. DESIGN: Retrospective case series. ANIMALS: 34 dogs that underwent biliary surgery. PROCEDURES: Data extracted from medical records included sex, breed, body weight, age at surgery, history and clinical examination findings, preoperative and postoperative CBC, serum biochemical panel and coagulation profiles results, abdominal ultrasonographic findings, results of bacteriologic culture and histologic examination, surgical findings, postoperative complications, and survival time. Follow-up information was obtained from medical records or phone conversations with owners and referring veterinarians. RESULTS: Primary biliary findings included gallbladder mucocele (n = 20 dogs), inflammatory diseases (4), trauma (3), and neoplasia (1). Secondary biliary diseases included pancreatitis (n = 4), pancreatic neoplasia (1), and duodenal perforation (1). One- and 2-year survival rates were both 66%. Increasing age; gamma-glutamyltransferase activity; preanesthetic heart rate; BUN, phosphorus, and bilirubin concentrations; and the use of biliary diversion procedures were risk factors for death, although pancreatitis was not. However, poor long-term survival was associated with pancreatitis. CONCLUSIONS AND CLINICAL RELEVANCE: Long-term prognosis was guarded after biliary surgery in dogs. However, dogs that survived the early postoperative period had good long-term prognosis. Dogs with pancreatitis had poor prognosis. Overall, the prognosis was worse for dogs that underwent a biliary diversion, compared with dogs that did not.     

EVALUATION OF CONTRAST‐ENHANCED ULTRASONOGRAPHY AS A METHOD FOR DETECTING GALLBLADDER NECROSIS OR RUPTURE IN DOGS

Gall bladder necrosis and rupture are life‐threatening conditions in dogs requiring surgical intervention and early diagnosis is essential. Human patients with suspected gall bladder necrosis/rupture are commonly evaluated with contrast‐enhanced ultrasonography (CEUS), however this procedure has not been described in dogs with suspected gall bladder necrosis/rupture. In a prospective diagnostic cohort study, CEUS (using SonoVue contrast medium) was performed in 93 dogs with gallbladder lesions identified by abdominal conventional ultrasonography. Necrosis/rupture was identified by CEUS as a focal lack of enhancement of the gallbladder wall. Dogs with positive CEUS finding for necrosis/rupture (complete lack of regional wall enhancement) underwent immediate surgery as did dogs with other biliary disorders requiring surgery. Dogs with negative CEUS findings or those not requiring surgery were managed medically. In cases undergoing surgery, necrosis/rupture was confirmed intraoperatively (and via histopathology). Absence of necrosis/rupture was confirmed either intraoperatively (via histopathology) or was assumed to be absent by complete recovery with medical management. Forty‐nine dogs underwent surgery and cholecystectomy: 24 had necrosis/rupture. CEUS was more accurate (100% sensitive and specific) in diagnosing gallbladder wall necrosis/rupture than conventional ultrasonography (75% sensitive and 81% specific) (P < 0.03). In conclusion, CEUS provides accurate characterization of gallbladder wall integrity that can impact decisions regarding clinical management, either surgical or medical.     

RADIOGRAPHIC APPEARANCE OF PRESUMED NONCARDIOGENIC PULMONARY EDEMA AND CORRELATION WITH THE UNDERLYING CAUSE IN DOGS AND CATS

Noncardiogenic pulmonary edema is an important cause of respiratory disease in dogs and cats but few reports describe its radiographic appearance. The purpose of this retrospective case series study was to describe radiographic findings in a large cohort of dogs and cats with presumed noncardiogenic pulmonary edema and to test associations among radiographic findings versus cause of edema. Medical records were retrieved for dogs and cats with presumed noncardiogenic edema based on history, radiographic findings, and outcome. Radiographs were reviewed to assess lung pattern and distribution of the edema. Correlation with the cause of noncardiogenic pulmonary edema was evaluated with a Fisher's exact test. A total of 49 dogs and 11 cats were included. Causes for the noncardiogenic edema were airway obstruction (n = 23), direct pulmonary injury (n = 13), severe neurologic stimulation (n = 12), systemic disease (n = 6), near‐drowning (n = 3), anaphylaxis (n = 2) and blood transfusion (n = 1). Mixed, symmetric, peripheral, multifocal, bilateral, and dorsal lung patterns were observed in 44 (73.3%), 46 (76.7%), 55 (91.7%), 46 (76.7%), 46 (76.7%), and 34 (57.6%) of 60 animals, respectively. When the distribution was unilateral, pulmonary infiltration involved mainly the right lung lobes (12 of 14, 85.7%). Increased pulmonary opacity was more often asymmetric, unilateral, and dorsal for postobstructive pulmonary edema compared to other types of noncardiogenic pulmonary edema, but no other significant correlations could be identified. In conclusion, noncardiogenic pulmonary edema may present with a quite variable radiographic appearance in dogs and cats.