Ultrasonography as a diagnostic and prognostic approach in cattle and buffaloes with fatty infiltration of the liver

The aim of the present study was to determine whether ultrasonographic evaluation of the hepatic parenchyma could be used as a diagnostic and prognostic approach in cows and buffaloes with hepatic lipidosis. For this purpose, cows (n=16) and buffaloes (n=10) with fatty infiltration of the liver were examined by ultrasonography. Treated cows and buffaloes were monitored for hepatic changes ultrasonographically, biochemically and histologically. Clinical findings were non-specific and included anorexia, recumbency, muzzle necrosis, and icteric mucosal membranes. Laboratory data revealed neutrophilia, hyper gamma-globulinemia, elevated activities of aspartate aminotransferase, gamma-glutamyl transpeptidase, creatine kinase and lactate dehydrogenase, and high concentrations of insulin, total bilirubin, non-esterified fatty acids and beta-hydroxyl butyric acid. Laboratory results 7, and 21 days after treatment showed progressive improvement in the chemistry profile. On admission, ultrasonographic examination of the hepatic parenchyma in cows and buffaloes revealed either increased or decreased hepatic echogenicity; histologic examination revealed marked fatty infiltration of the hepatocytes. One week after treatment, the hepatic parenchyma was visualized easily, liver boundaries were clearly imaged, and histologic examination of hepatic specimen showed a moderate degree of fatty infiltration. Three weeks after treatment, the hepatic parenchyma was almost similar to normal, the hepatic and portal blood vessels could be easily imaged, and the histologic picture had greatly improved where the liver resembled the normal organ. Six cows and seven buffaloes made a full recovery while the remaining ten cows and three buffaloes were slaughtered and thoroughly examined postmortem. Ultrasonography showed a good correlation with histologic and laboratory findings.     

Clinicopathological and ultrasonographic findings in 40 water buffaloes (Bubalus bubalis) with traumatic pericarditis

Forty buffaloes with traumatic pericarditis were examined to characterise the ultrasonographic findings in buffaloes with traumatic pericarditis, determine the extent of the lesions and assess the prognosis. The most noticeable clinical presentations were presternal oedema (73 per cent) and jugular and mammary vein distension (88 per cent). Laboratory findings included neutrophilic leucocytosis, elevated total protein concentration, hypoalbuminaemia, hypergammaglobulinaemia and increased concentration of free fatty acids. Ultrasonographically, fluid in the pericardium appeared as either mild or massive anechoic accumulations containing fibrin threads or were imaged as homogenous, echogenic pericardial effusions. Moderate to severe corrugation of the reticular wall was observed. Deposits of fibrinous tissue interspersed with fluid pockets were seen between the reticulum, dorsal ruminal sac and diaphragm. Perireticular and mediastinal abscesses were imaged and appeared as echogenic lines with anechoic, echogenic, homogenous or heterogeneous contents. Additional ultrasonographic findings included hepatomegaly, dilation of the caudal vena cava, hepatic and portal veins, ascites, echogenic pleural effusions and vegetations of the tricuspid, mitral and pulmonary valves. The ultrasonographic findings were confirmed at postmortem examination.     

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.     

Suppurative cholangitis in cats

Suppurative cholangitis in 5 aged cats was characterized clinically by weight loss, depression, dehydration, icterus, and fever. The major abnormal laboratory findings were a severe left shift of WBC and a high, conjugated bilirubin concentration consistent with an inflammatory process and cholestasis. Gross pathologic findings included periductal biliary fibrosis (4 cats), periductal pancreatic fibrosis (2 cats), cholelithiasis (2 cats), deformation of the gallbladder (2 cats), and chronic interstitial pancreatitis (2 cats). Histopathologic findings in all cases were portal hepatic fibrosis, biliary hyperplasia, and suppurative exudate within dilated intrahepatic biliary ducts. Weight loss and portal fibrosis were suggestive of chronic, intermittent illness. The pathogenesis appeared to involve invasion of the bile duct by enteric bacteria. Cholangitis was observed to occur in association with pancreatitis, cholelithiasis, or anatomic abnormalities of the biliary tract.     

Ultrasonographic evaluation of abdominal distension in 52 camels (Camelus dromedarius)

The purpose of this study was to assess the diagnostic value of ultrasonography in the evaluation of abdominal distension in 52 camels (Camelus dromedarius). The conditions included trypanosomiasis (n=35), intestinal obstruction (n=12) and ruptured urinary bladder (n=5). Fifteen clinically normal camels were included as controls. Transabdominal and transrectal ultrasonography was carried out on all camels. In animals with trypanosomiasis, ultrasonographic findings included accumulation of massive amounts of hypoechoic abdominal fluids where liver, intestine, kidney, spleen and urinary bladder were imaged floating. Except in two cases of bile duct calcification and one of hepatic abscessation, no detectable abnormal sonographic lesions were detected while imaging the hepatic and renal parenchyma, and the heart and its valves and major blood vessels. In camels with intestinal obstruction, ultrasonographic findings included distended intestinal loops with markedly reduced or absent motility. In one camel, the intestinal lumen contained localised hyperechoic material that was consistent with a foreign body. Hypoechoic fluid with or without fibrin was seen between intestinal loops. In camels with ruptured urinary bladder, ultrasonographic findings included collapsed and perforated bladder, echogenic blood clots within the urinary bladder and peritoneal cavity, increased thickness of the bladder wall, floating intestines in hypoechogenic fluid and echogenic calculi within the urethra. Ultrasonography was considered a useful tool for the evaluation of dromedary camels with abdominal distension.     

Ultrasonographic findings in three cows with chronic ragwort (Senecio alpinus) poisoning

Three cows with regwort (Senecio alpinus) poisoning were examined clinically, haematologically and ultrasonographically, and biopsy specimens of the liver were examined histologically. At the end of the study, the cows were euthanased and examined postmortem. The major clinical signs included severely disturbed general demeanour and behaviour, and severe diarrhoea. One cow was photosensitive. The activities of liver enzymes and the concentration of bilirubin were high in all of the cows. In two of the cows, ultrasonographic examination revealed a heavy accumulation of abdominal fluid, which was diagnosed as non-inflammatory ascites. In all the cows, the liver parenchyma was heterogeneous, and cows 1 and 2 had multiple echogenic foci 5 to 10 mm in diameter. In cow 3, the facies diaphragmatica of the liver appeared irregular in outline owing to the presence of nodules which were approximately 5 cm in diameter. The liver was also greatly enlarged and extended almost to the linea alba ventrally and beyond the reticulum cranially. All the cows had portal hypertension and the portal vein was dilated, resulting in oedema of the walls of the gall bladder, the small intestines and the omentum. The diameter of the caudal vena cava was reduced as a result of the impaired hepatic circulation. Histological examination of liver biopsy specimens revealed severe hepatic fibrosis in all the cows.     

Ultrasonographic findings in horses with cholelithiasis: eight cases (1985-1987)

Cholelithiasis and/or obstructive biliary tract disease was diagnosed ultrasonographically in 8 horses, 5 to 15 years old. Ultrasonographic findings revealed greater than normal amount of hepatic parenchyma in the right side of the abdomen in 8 horses and in the left side in 3 horses. The echogenicity of the liver was greater than normal, and thick distended bile ducts were seen in all horses. Choleliths were imaged ultrasonographically in 6 horses. Subsequently, postmortem findings in 6 horses revealed periportal and intralobular fibrosis, moderate bile duct dilatation, proliferation, and cholestasis. One or more choleliths were found in all horses. Ultrasonographic findings accurately depicted the histologic changes in the hepatic parenchyma in horses with cholelithiasis.     

COMPARISON BETWEEN ULTRASONOGRAPHIC AND CLINICAL FINDINGS IN 43 DOGS WITH GALLBLADDER MUCOCELES

Cholecystectomy is the current standard recommended treatment for dogs with gallbladder mucoceles. However, medical management with monitoring has also been recommended for asymptomatic dogs. The purpose of this retrospective study was to compare ultrasonographic patterns of gallbladder mucoceles with clinical disease status in a group of dogs. For each included dog, the ultrasonographic pattern of the mucocele was classified into one of six types: type 1, immobile echogenic bile; type 2, incomplete stellate pattern; type 3, typical stellate pattern; type 4, kiwi like pattern and stellate combination; type 5, kiwi like pattern with residual central echogenic bile; and type 6, kiwi like pattern. A total of 43 dogs were included. Twenty‐four dogs, including 11 dogs with gallbladder rupture, were symptomatic. Nineteen dogs were asymptomatic. Cholecystectomy (n = 19), medical therapy (n = 17), or monitoring (n = 6) treatments were applied according to clinical signs and owners’ requests. One dog suspected of having gallbladder rupture was euthanized. Frequencies of gallbladder mucocele patterns were as follows: type 1 = 10 (23%), type 2 = 13 (30%), type 3 = 5 (12%), type 4 = 11 (26%), type 5 = 4 (9%), and type 6 = 0. In dogs with gallbladder rupture, type 2 (8/13) was the most common. No significant correlations were found between ultrasonographic patterns of gallbladder mucoceles and clinical disease status or gallbladder rupture. Findings indicated that ultrasonographic patterns of gallbladder mucoceles may not be valid bases for treatment recommendations in dogs.     

Hepatocyte apoptosis in dairy cows with fatty infiltration of the liver

The objective of the present study was to analyse the apoptotic process of liver cells in dairy cows with fatty infiltration of the liver using indicators of DNA damage and immunohistochemistry. For this purpose, sixteen dairy cows with fatty liver were examined. On clinical examination, the physical condition of the animals was fair in nine and poor in seven cows. The most dominant clinical signs were reduced ruminal motility, inappetance and/or anorexia and recumbency. Postmortem examination, in seven cases, revealed enlarged liver (18–33 kg), icteric carcasses and distended gallbladder. Laboratory results included neutrophilia, hypochloraemia, decreased concentrations of total bilirubin and increased concentrations of β-hydroxy butyric acid, non-esterified fatty acids and insulin. The activities of aspartate aminotransferase, γ-glutamyl transpeptidase, creatine kinase and lactate dehydrogenase were high. Histopathological examination of hepatic specimen showed lipid drops in cytosol with indistinct cellular membranes. In control hepatic cells, the DNA was tightly compressed and maintained the circular disposition of the normal nucleus. However, in the diseased cows, the damaged DNA migrated from the core toward the anode, forming a tail of a comet. Compared to controls, numerous ssDNA and caspase-3-positive cells were detected in the liver. To the authors’ knowledge, this is the first study to document accelerated apoptosis of hepatocytes in dairy cows with fatty infiltration of the liver.     

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.     

Hepatocyte apoptosis in dairy cows with fatty infiltration of the liver

The objective of the present study was to analyse the apoptotic process of liver cells in dairy cows with fatty infiltration of the liver using indicators of DNA damage and immunohistochemistry. For this purpose, sixteen dairy cows with fatty liver were examined. On clinical examination, the physical condition of the animals was fair in nine and poor in seven cows. The most dominant clinical signs were reduced ruminal motility, inappetance and/or anorexia and recumbency. Postmortem examination, in seven cases, revealed enlarged liver (18-33kg), icteric carcasses and distended gallbladder. Laboratory results included neutrophilia, hypochloraemia, decreased concentrations of total bilirubin and increased concentrations of β-hydroxy butyric acid, non-esterified fatty acids and insulin. The activities of aspartate aminotransferase, γ-glutamyl transpeptidase, creatine kinase and lactate dehydrogenase were high. Histopathological examination of hepatic specimen showed lipid drops in cytosol with indistinct cellular membranes. In control hepatic cells, the DNA was tightly compressed and maintained the circular disposition of the normal nucleus. However, in the diseased cows, the damaged DNA migrated from the core toward the anode, forming a tail of a comet. Compared to controls, numerous ssDNA and caspase-3-positive cells were detected in the liver. To the authors' knowledge, this is the first study to document accelerated apoptosis of hepatocytes in dairy cows with fatty infiltration of the liver.     

Hepatic encephalopathy in a pregnant mare: identification of histopathological changes in the brain of a mare and fetus

An 11-year-old Thoroughbred broodmare was evaluated for suspected hepatic dysfunction. Clinical signs of hepatic encephalopathy were evident at admission. Hepatic ultrasonographic evaluation revealed an increase in hepatic size, rounded borders and normal echogenicity. There was no evidence of cholelithiasis or bile duct distention. Increased activity of hepatic enzymes, increased bile acid and bilirubin concentration and an increased ammonia concentration were supportive of a diagnosis of hepatic disease and hepatic encephalopathy. Histopathological evaluation of a liver biopsy specimen was consistent with chronic active hepatitis. The mare was treated with intravenous fluids and antimicrobials, pentoxyfilline, branched-chain amino acids and dietary manipulation. Clinical improvement was observed initially; however, 3 weeks later, deterioration in the mare's condition necessitated euthanasia. Pathological lesions at necropsy were restricted to the liver and brain. The liver was diffusely firm with a prominent reticular pattern on the cut surface. A large choledocholith was present in the main bile duct of the left liver lobe. Histopathological examination of the liver revealed severe fibrosis, with hyperplastic bile ducts and mononuclear and neutrophilic inflammation. Pathological changes consistent with hepatic encephalopathy, (Alzheimer type II cells), were evident in the cerebrum of both the mare and the fetus.     

IMAGING DIAGNOSIS—SPONTANEOUS INTRAMURAL CANINE DUODENAL HEMATOMA

A 9‐year‐old neutered female Pug with a 2‐week history of pancreatitis was presented for dyspnea, icterus, and intractable vomiting. Sonographically, the gallbladder, intrahepatic bile ducts, and common bile duct were distended. The pancreas was hypoechoic with hyperechoic peripancreatic fat. A mildly heterogeneous intramural mass was present in the muscularis layer of the descending duodenum. A presumptive diagnosis of pancreatitis and smooth muscle tumor of the duodenum leading to common bile duct obstruction was made. The dog died despite supportive care. Necropsy examination confirmed the presence of pancreatitis and an intramural duodenal hematoma.     

Diagnosis by ultrasonography of congestion of the caudal vena cava secondary to thrombosis in 12 cows

This paper describes the clinical, ultrasonographic, radiographic and postmortem findings in 12 cows with thrombosis of the caudal vena cava. The principal clinical signs were chronic bronchopneumonia and fever in 11 cows; one cow had epistaxis and one cow bled from the mouth; eight cows had anaemia and leucocytosis, and the clotting time for the glutaraldehyde test was markedly decreased in all the cows; in nine of the cows the activity of gamma-glutamyltransferase was high, suggesting chronic hepatic congestion. The most important ultrasonographic finding was congestion of the caudal vena cava attributable to thrombosis of the vein. In all the cows the caudal vena cava was round to oval on cross-section, rather than the normal triangular shape. The hepatic, splenic and portal veins were dilated in five, three and one cow, respectively. The results of radiography and endoscopy supported a diagnosis of bronchopneumonia, but there were radiographic changes in the diaphragmatic lung lobes that supported a diagnosis of vena caval disease in only four cows. Postmortem there was a thrombosis of the caudal vena cava in all the cows, and the thrombi were located in the thoracic, subphrenic and abdominal part of the caudal vena cava at the level of the liver in four, one and seven cows, respectively. In three cows, the thrombus was situated where a hepatic abscess had broken into the caudal vena cava, and in one cow it was at the site of a diaphragmatic abscess. In another cow, there was a fistula between the major bronchus of the right diaphragmatic lung lobe and the caudal vena cava where the thrombus was situated. Three cows had liver abscesses that had not broken into the caudal vena cava. There was severe bronchopneumonia in 11 of the cows, some of which also had multiple pulmonary abscesses.     

HEPATIC ULTRASONOGRAPHIC AND PATHOLOGIC FINDINGS IN DOGS WITH CANINE SURPERFICIAL NECROLYTIC DERMATITIS

A unique, "honeycomb" pattern was found on ultrasonographic evaluation of the liver of 5 dogs with canine superficial necrolytic dermatitis (hepatocutaneous syndrome). This pattern consisted of variably-sized, hypoechoic regions measuring 0.5–1.5 cm in diameter surrounded by highly echogenic borders. Histologically, the hypoechoic regions corresponded to distinct regenerative nodules bounded by severely vacuolated (fat-laden) hepatocytes, numerous bile ductules, and a network of reticulin and fine collagen fibers representing remnants of collapsed hepatic lobules. While certain features of the architectural disruption were characteristic of cirrhosis, the lesion lacked the extensive fibrosis and reduced liver size usually associated with chronic cirrhosis. To our knowledge, this hepatic ultrasonographic pattern has only been seen with canine superficial necrolytic dermatitis. Therefore, it appears to be pathognomonic in a dog with questinable skin lesions. A liver biopsy is required to confirm the unique histopathologic features of the hepatopathy found in this syndrome.     

Gallbladder perforation associated with cholelithiasis and cholecystitis in a dog

A four-year-old female Japanese akita was admitted with icterus, ascites and chronically elevated serum bilirubin and liver enzymes. Abdominal ultrasonography revealed a diffusely thickened, hyperechoic gallbladder wall with a focal defect, hepatic lymphadenopathy and a large volume of anechoic fluid within the peritoneal space. Diagnosis of biliary tract rupture with bile peritonitis was based on the findings of bile and suppurative exudate in peritoneal aspirates. A perforated gallbladder and cholelithiasis were found on exploratory celiotomy, while histopathology revealed chronic suppurative cholecystitis. The dog recovered uneventfully after cholecystectomy. Although rare, the triad of cholelithiasis, cholecystitis and gallbladder perforation should be considered after detection of one of these conditions.     

SONOGRAPHIC EVALUATION OF EXPERIMENTAL BILE DUCT LIGATION IN THE DOG

The common bile duct was surgically ligated in five normal adult dogs. Ultrasonographic examinations of the gallbladder and biliary system were performed after duct ligation at intervals of 24 hours. The sequence of biliary system dilation was from the common duct to the peripheral intrahepatic ducts. Common duct enlargement was evident in 24–48 hours, while peripheral biliary duct dilation was recognized by five to seven days after obstruction. When compared with hepatic and portal veins, dilated biliary ducts were more tortuous and had irregular branching patterns. Gross pathologic changes were correlated with ultrasonographic findings at seven, 14, 15, 18 and 21 days after obstruction.     

Anatomicopathological study of vascular and biliary systems using cast samples of Fasciola-infected bovine livers

In 117 livers with fascioliasis, this study was focused on the number of Fasciola, the number and intrahepatic localization of affected hepatic ducts and bile ducts, and the degree of fibrosis in the hepatic segments and bile ducts. The degree of pathological changes in bile ducts caused by fascioliasis was classified into five levels. The site of Fasciola habitation was most often the hepatic ducts of the porta hepatis: it was the left hepatic duct in 101 livers and the right hepatic duct in 88 livers. Casts were prepared by infusing synthetic resin into the hepatic arterial, portal, hepatic venous and biliary systems of 15 bovine livers with fascioliasis and then examined. In the left lobe, quadrate lobe, and caudate process where atrophic fibrosis was noted, the bile ducts became rod-shaped by losing branches, and the samples resembled dead branches of liver. Portal branches were thinned or completely terminated with marked fibrosis. Fine and irregular newly formed bile ducts not parallel with portal branches were observed in livers with markedly chronic fascioliasis. Distal portal branches in the right lobe, caudate lobe, and papillary process showed hypertrophic proliferative changes. The arterial system was generally well developed in thickened walls of bile ducts and formed vascular beds, and surrounded the bile ducts as tubes. In livers with severe fibrosis, capillaries were markedly developed and resembled glass cotton.     

Statistical relevance of ultrasonographic criteria in the assessment of diffuse liver disease in dogs and cats

OBJECTIVE: To determine whether objectively applied ultrasonographic interpretive criteria are statistically useful in differentiating among 7 defined categories of diffuse liver disease in dogs and cats. SAMPLE POPULATION: Ultrasonographic images of 229 dogs and 104 cats. PROCEDURES: Liver parenchymal or related sonographic criteria established by the authors were retrospectively and independently applied by 3 radiologists who were not aware of patient status or patient laboratory data. Seven histologic or cytologic categories of diffuse (infiltrative but not nodular) liver diseases were jointly established by the authors and included normal liver; inflammation; round-cell neoplasia; non-round-cell infiltrative, prenodular (early) metastatic neoplasia; lipidosis; vacuolar hepatopathy; and other. Liver parenchymal sonographic criteria included parenchymal sound attenuation with increasing depth, comparative organ echogenicity (liver, spleen, and kidneys), diffuse or patchy hyperechoic or hypoechoic echotexture, uniform or coarse echotexture, portal venous clarity, and liver lobe geometry. Related extrahepatic criteria included gallbladder wall thickness, bile duct diameter, amount and character of gallbladder precipitate, nondependent shadowing in the gallbladder, hepatic vein diameter versus caudal vena cava diameter, peritoneal fluid, spleen echotexture (normal vs abnormal [characterized]), and kidney echotexture. Ultrasonographic criteria were statistically compared to the 7 categories of diffuse liver disease in search of clinically exploitable relationships. RESULTS: Statistical evaluation of the applied ultrasonographic criteria did not yield clinically acceptable accuracy for discrimination among the 7 categories of diffuse liver diseases (including normal liver) in either species. CONCLUSIONS AND CLINICAL RELEVANCE: Criterion-based ultrasonographic appearance was insufficient to discriminate among canine and feline diffuse infiltrative liver diseases.     

CD44 expression in the bile duct epithelium is related to hepatic fibrosis in nonalcoholic steatohepatitis rats induced by a choline-deficient,methionine-lowered, L-amino acid diet

Nonalcoholic steatohepatitis is a lifestyle-related disease and an increasing threat worldwide. Hepatic fibrosis, which results from chronic hepatic diseases including nonalcoholic steatohepatitis, is closely correlated with mortality among hepatic lesions, such as steatosis and inflammation. Thus, it is important to identify factors that can serve as diagnostic and therapeutic targets for hepatic fibrosis. In this study, we examined the function of CD44 in the development of hepatic fibrosis in choline-deficient, methionine-lowered, L-amino-acid diet-fed rats, especially with respect to the proliferation of bile duct epithelium. Male Fischer 344 rats were fed a choline-deficient, methionine-lowered, L-amino-acid diet for 2, 4, 13, or 26 weeks. This diet decreased the body weight; increased the levels of serum parameters indicating liver injury, such as aspartate and alanine aminotransferase; upregulated inflammation- and fibrosis-related gene expression in the liver; and resulted in the development of hepatic lesions, including fatty changes in hepatocytes, inflammatory cell infiltration, and fibrosis. Hepatic hyaluronan was synthesized and deposited in the liver tissue. The expression of both CD44 mRNA and protein was significantly increased throughout the experimental period. CD44 protein was observed in some of the bile duct epithelium, around which hyaluronic acid was deposited, and these bile duct lesions were concordant with the area of hepatic fibrosis. Thus, CD44 expressed in the bile duct epithelium may be a target for controlling nonalcoholic steatohepatitis-related hepatic fibrosis.