Chronic hepatitis and hepatocellular carcinoma associated with persistent woodchuck hepatitis virus infection

The livers of 16 woodchucks with naturally acquired chronic infection with woodchuck hepatitis virus were examined both grossly and histologically in 14 biopsy specimens and seven necropsy specimens. Fifteen woodchucks had lesions characteristic of chronic hepatitis; ten of these had chronic active hepatitis, four had chronic persistent hepatitis, and one had cirrhosis with nodular regeneration. In one woodchuck there was massive hepatic necrosis attributed to infection with an unclassified protozoan. Thirteen woodchucks had primary hepatocellular carcinoma. Metastasis to the lung was observed in only one woodchuck. These results were compared to liver lesions in 149 woodchuck hepatitis virus-negative woodchucks. Chronic hepatitis comparable to that associated with woodchuck hepatitis virus infection was not observed in woodchuck hepatitis virus-negative woodchucks although in one, a single, small hepatocellular adenoma was found.     

Hepatic yersiniosis in a cougar (Felis concolor).

A cougar (Felis concolor) was diagnosed with hepatic yersiniosis by bacterial culture and histopathology. The animal had a 2-week history of anorexia and jaundice before its death. Grossly, the liver exhibited caseo-necrotic foci. Histopathologically, there was necrotizing and suppurative hepatitis, with large numbers of intralesional gram-negative coccobacilli. Additional hepatic lesions included central vein thrombosis, lymphoplasmacytic portal hepatitis, and capsulitis. Yersinia pseudotuberculosis coccobacilli were isolated in pure culture from the hepatic lesions. Because the hepatic lesions in this animal resemble those of other zoonotic diseases, such as plague and tularemia, veterinarians and laboratory personnel who handle samples should take adequate safety precautions. This report is the first to describe the pathology associated with hepatic yersiniosis in a cougar.     

Investigation of a syndrome of sudden death, splenomegaly, and small intestinal hemorrhage in farmed deer

A newly recognized syndrome, characterized by sudden death of farmed deer that are in good to excellent nutritional condition, with lesions of small intestinal mucosal hemorrhage and splenomegaly, is described. Other frequently observed lesions were small intestinal mucosal necrosis, abomasal hemorrhage, random hepatic necrosis, and multifocal hepatic congestion. Clostridium perfringens type A was isolated in high numbers from the intestines of many of the deer affected by the syndrome; however, the numbers were not significantly different from those of control deer. The syndrome did not appear to be related to dietary or any other specific management factors and a definitive cause of the syndrome was not identified.     

Primary liver disease in the horse

The clinical signs of liver disease are highly variable and non-specific. Irrespective of the cause or the duration of liver disease, more specific clinical signs, e.g. hepatic encephalopathy, become apparent in the advanced stages of the disease. Due to the non-specific clinical signs, the possible diagnosis of liver disease is frequently not taken into consideration. However, measurement of the plasma or serum concentrations of total bile acids and gamma glutamyl transferase (gamma GT) may provide valuable diagnostic information. The specific diagnosis can be confirmed by ultrasound examination of the liver and histological examination of a liver biopsy specimen. The most frequently documented liver diseases are acute hepatic necrosis, chronic hepatitis caused by pyrrolizidine alkaloids, cholelithiasis, and haemochromatosis. Immediate treatment with antibiotics and polyionic fluids, in association with supportive nutritional care, is usually necessary to maintain the horse until sufficient liver regeneration occurs to provide adequate function. The use of corticosteroids is contraindicated, except for patients with chronic active hepatitis. In some cases, e.g. portosystemic shunts or cholelithiasis, surgical intervention is indicated. Liver disease may be more common than is currently appreciated since little accurate information on the prevalence or incidence is available.     

Detection of Bartonella henselae and Bartonella clarridgeiae DNA in hepatic specimens from two dogs with hepatic disease

A 4-year-old Basset Hound and a 6-year-old Doberman Pinscher were referred for diagnostic evaluation following documentation of persistently increased hepatic enzyme activities and hepatic dysfunction. Histologic evaluation of hepatic biopsy specimens from the 2 dogs revealed granulomatous hepatitis in the Basset Hound and lymphocytic hepatitis with fibrosis and copper accumulation in the Doberman Pinscher. No etiologic agents were identified histologically. Bartonella henselae DNA was subsequently amplified from hepatic tissue from the Basset Hound and Bartonella clarridgeiae was amplified from hepatic tissue from the Doberman Pinscher. Amplification was performed with a polymerase chain reaction assay incorporating primers that target a portion of the 16S-23S rRNA intergenic spacer region. Both dogs were treated with azithromycin, in combination with a variety of other medications and herbal treatments, and improved clinically. Identification of Bartonella DNA in these dogs indicates the need for future prospective studies to determine the clinical relevance of Bartonella spp infection in dogs with hepatic disease.     

Pathogenicity studies with a strain of fowl adenovirus serotype 8 (VRI-33) in chickens

Experiments were undertaken to study the pathogenesis of VRI-33, a strain of fowl adenovirus serotype 8 isolated from the liver of a broiler chicken with inclusion body hepatitis. A 30% death rate resulted from oral infection of one-day-old specific pathogen free chickens with 10⁶ plaque forming units of VRI-33. Chickens 10, 14, 21 and 28 days of age did not die following infection via natural routes but there were some motalities following infection via parenteral routes. Immunodepression by neonatal cyclophosphamide treatment, followed by infection with VRI-33 via non-parenteral routes, caused varying degrees of hepatitis with basophilic intranuclear inclusion bodies in hepatocytes. The mortality rate of cyclophosphamide-treated, VRI-33 infected chickens, was not significantly altered by post-infection temperature stress. Infection with infectious bursal disease virus, followed by infection with VRI-33 via natural routes at 14 days of age, was not associated with mortalities.     

Copper-associated chronic hepatitis in Labrador Retrievers

This study summarizes the clinical and pathologic findings in 15 Labrador Retrievers with copper-associated chronic hepatitis (CACH). Our hypothesis was that this form of hepatitis is caused by a defect in hepatic copper metabolism, which most likely originates from a genetic defect. Affected Labradors consisted of 11 female and 4 male Labrador Retrievers. Eight family members of 2 of these patients were examined prospectively, as were 6 unrelated healthy Labrador Retrievers. All dogs were registered at the breed club. The average age at clinical presentation was 7 years (range, 2.5-10.5 years). All dogs were presented for anorexia, which was associated with vomiting in 8 patients. The diagnosis of CACH was based on histologic examination of liver biopsy specimens in all dogs, including semiquantitation of copper. A disproportionate increase in alanine aminotransferase (ALT) activity relative to alkaline phosphatase (ALP) activity, as well as the centrolobular localization of copper and the association of copper accumulation with hepatic lesions, suggested a primary copper storage disease rather than primary cholestatic liver disease causing copper accumulation. Mean hepatic copper concentration measured in related Labradors was 1,317 microg/g dry weight liver (range, 402-2,576 microg/g). Mean hepatic copper concentration of unrelated normal Labradors was 233 microg/g dry weight liver (range, 120-304 microg/g). Our findings support the hypothesis that a hereditary form of hepatitis occurs in Labrador retrievers and is caused by a defect in hepatic copper metabolism.     

Chronic hepatitis in the dog

Chronic hepatitis in the dog encompasses a diverse group of liver diseases characterised by a mixed inflammatory infiltrate within the hepatic parenchyma but with multiple causes. The aetiology is often unknown. Potential causes include hepatic copper accumulation, drugs, infections, and, speculatively, immune-mediated disease. Diagnosis is made based on liver biopsy. Treatment is predominantly supportive, while corticosteroids may be indicated in selected cases with idiopathic chronic hepatitis.     

Identification of domestic cat hepadnavirus from a cat blood sample in Japan

The hepatitis B virus (Hepadnaviridae) induces chronic hepatitis and hepatic cancer in humans. A novel domestic cat hepadnavirus (DCH) was recently identified in several countries, however, the DCH infection status of cats in Japan is unknown. Therefore, we investigated the DCH infection rate of 139 cat samples collected in Japan. We identified one positive blood sample (0.78%) from a 17-year-old female cat with chronically elevated alanine aminotransferase. Phylogenetic analysis demonstrated that the DCH strain identified in this study is genetically different from strains in other countries. Further investigations are required to elucidate the evolution of DCH and the impact of DCH infection on hepatic diseases in domestic cats.     

An unusual case of inclusion body hepatitis in a cockerel

This report describes inclusion body hepatitis in a 12-week-old leghorn-type cockerel. The cockerel had come from a specific-pathogen-free flock and was reared in a positive-pressure isolator until 6 weeks old. Grossly, the cockerel was jaundiced, and the liver was swollen and had small white foci throughout. Histologically, there were foci of hepatic necrosis and basophilic inclusion bodies in the nuclei of numerous hepatocytes. A fowl adenovirus, isolated from the liver, was found to belong to serotype 2/12. The bursa of Fabricius had some degenerative changes, but these were not consistent with infectious bursal disease, nor was there evidence of seroconversion to infectious bursal disease virus in the remaining chickens.     

Current concepts in the treatment of canine chronic hepatitis

Chronic hepatitis is a common disorder in dogs seen by general practitioners. Several new drugs have been marketed for treating this disease. Unfortunately, there are few controlled studies that examine the efficacy of these medications for the treatment of canine chronic hepatitis. A rational therapeutic approach can be implemented based on histopathologic findings of a liver biopsy. A liver biopsy is essential for establishing a definitive diagnosis and guiding the optimal therapy. The biopsy allows characterizing the inflammatory process, quantitating hepatic copper concentrations, and determining if fibrosis is present. Copper associated hepatopathy is treated with zinc and copper chelators. Idiopathic chronic hepatitis is thought to be immune mediated. The treatment of idiopathic chronic hepatitis consists of controlling inflammation (prednisone, azathioprine), reversing fibrosis (colchicine), and protecting against oxidant damage (vitamin E, ursodeoxycholic acid, S-adenosylmethionine). The prognosis for chronic hepatitis is quite variable. Dogs with end-stage disease have a poor prognosis, while dogs diagnosed earlier can have a mean survival of years. Early diagnosis and intervention are key to the successful treatment of dogs with chronic hepatitis.     

Immunohistochemical detection of canine adenovirus in paraffin sections of liver

An avidin-biotin immunoperoxidase procedure was optimized for detection of canine adenoviral antigens in formalin-fixed, paraffin-embedded liver. Long-term stability of viral antigen was shown by successful demonstration of virus in liver tissue preserved up to six years from dogs with infectious canine hepatitis. This immunohistochemical stain was applied to sections from livers with a wide range of inflammatory lesions. Examination of sections from 53 dogs yielded five livers with small amounts of adenovirus. An additional virus-positive liver was identified from a dog with no hepatic inflammation. Although a cause and effect relationship remains to be determined, these findings suggest a possible connection between canine adenovirus and spontaneous chronic hepatitis.     

Hepatobiliary Scintigraphy in the Evaluation of Feline Liver Disease

Hepatobiliary scintigraphy (HBS) was performed in 10 cats with histologically documented hepatobiliary disease. The scintigraphic patterns were classified into one of 5 categories: normal, primary hepatocellular dysfunction, primary in-trahepatic cholestasis, mixed hepatocellular and intrahe-patic cholestasis, and extrahepatic obstructive patterns. Initial attempts were made to correlate specific disease entities with HBS patterns, but a consistent relationship could not be determined. A correlation between the histological severity of a given hepatic disease and the HBS pattern was made. All cats (n = 5) with a mixed hepatocellular and intra-hepatic cholestasis scintigraphic pattern with normal gallbladder function had a histologically severe form of their individual hepatic disease. Three of the 4 cats with an intra-hepatic cholestasis pattern and normal hepatocellular and gallbladder function had histologically mild or moderate forms of their individual hepatic disease. One cat had an extrahepatic obstructive pattern where no radiopharmaceu-tical was identified in the gallbladder or small intestine by 3 hours postinjection. This study suggests that HBS can be useful in cats with hepatobiliary disease to assess the severity of hepatic dysfunction, and to determine if extrahepatic biliary obstruction is present. Correlation between HBS patterns and specific disease entities such as hepatic lipidosis or cholangitis-cholangiohepatitis syndrome could not be made in this study.     

Evidence of hepatitis A infection in immature rhesus monkeys

Forty immature (less than 2 years old) rhesus monkeys (Macaca mulatta) with marked increases in aspartate and alanine aminotransferase activities were examined. Serological and histopathological evaluations were done to determine if affected animals were infected with hepatitis A virus. Although no clinical signs of illness were noted in any of the monkeys, an excellent correlation was found between the increased serum aminotransferase values and seropositivity with the acute phase (IgM) HAVAB-M antibody. Histopathological evaluations of livers of selected animals revealed hepatic lesions consistent with those in chimpanzees and marmosets infected with hepatitis A virus: generalized activation of sinusoidal lining cells, focal hepatocellular necrosis with occasional acidophilic bodies, and cuffs of mononuclear cells in the portal areas. Although no animals were seropositive for HAVAB upon receipt from the breeding colony, a total of ten of 18 animals for which serological data were available had seroconverted to HAVAB positivity during the 4-month observation period. These results are consistent with hepatitis A infection in immature rhesus monkeys and indicate the potential significance of serological testing in animals in which hepatic function is being evaluated.     

Diagnosis of chronic active hepatitis in a miniature schnauzer

A 12-year-old male castrated miniature schnauzer was presented with a history of abdominal distension. Serum biochemical analysis and abdominal ultrasonography indicated hepatic disease. A wedge biopsy provided a diagnosis of chronic active hepatitis. A therapeutic regime was initiated to improve the quality of life and slow the progression of this disease is described.     

A multistep approach in the cytologic evaluation of liver biopsy samples of dogs with hepatic diseases

Cytologic criteria were evaluated for their diagnostic value in liver disease in dogs. Therefore, histopathologic and cytologic examination was performed on liver biopsy samples of 73 dogs with liver diseases and 28 healthy dogs. Logistic regression analysis was used to select the measured parameters to be included in a multistep approach. With the logistic regression method, different characteristic cytologic parameters could be defined for each histopathologic diagnosis. In malignant lymphoma of the liver, the presence of large numbers of lymphoblasts with a minimum of 5% of all cells was found. Clusters of epithelial cells with several cytologic characteristics of malignancy intermixed with normal hepatocytes were indicative of metastatic carcinoma or cholangiocellular carcinoma. Liver cells in hepatocellular carcinoma were characterized by a high nucleus/cytoplasm ratio, large cell diameters, increased numbers of nucleoli per nuclei, small numbers of cytoplasmic vacuoles, and frequently, small numbers of lymphocytes. Extrahepatic cholestasis was characterized by excessive extracellular bile pigment in the form of biliary casts, an increased number of nucleoli within hepatocytes, decreased hepatic cell size, and low numbers of lymphocytes. In destructive cholangiolitis, increased numbers of neutrophils and a small mean nuclear size within hepatocytes were seen. Acute and nonspecific reactive hepatitis are diagnosed based on the presence of moderate reactive nuclear patterns, including more pronounced chromatin, prominent nucleoli, increased numbers of inflammatory cells, excluding lymphocytes, and the absence of increased numbers of bile duct cell clusters. Increased number of mast cells also was indicative of nonspecific reactive hepatitis. Important cytologic criteria for the diagnosis of liver cirrhosis, in addition to chronic hepatitis, are intracellular bile accumulation and increased numbers of bile duct cell clusters. In summary, the stepwise approach based on logistic regression presented in this study might be helpful in the objective cytologic diagnosis of hepatic diseases.     

PCR screening for candidate etiological agents of canine hepatitis

PROBLEM ASSESSED: Hepatitis, either acute or chronic, is a relatively common hepatic disease in dogs. Several forms of canine hepatitis can occur, some with a defined cause, most cases have an unknown etiology. The similarities between canine hepatitis and human viral hepatitis suggest that canine hepatitis may have a viral etiology too. OBJECTIVE: To test liver tissue of dogs with hepatitis for the presence of candidate agents based on their known association with hepatitis in other mammals. METHODS AND APPROACH: The following infectious agents were tested by PCR: Hepadnaviridae, Helicobacter spp., Leptospira spp., Borrelia spp., hepatitis A virus, hepatitis C virus and hepatitis E virus. Also canine adenovirus and parvovirus were included. Ninety-eight liver tissue samples of dogs with various histologically diagnoses forms of hepatitis were tested. Primers were designed on conserved regions in the genome of each of these agents, to increase the likelihood of detection by PCR. To further increase sensitivity, nested PCRs for all agents were designed. Finally, for each agent a nested short primer PCR (SPP) was performed. RESULTS: None of these agents were detected by nested PCR and nested SPP. However, in two acute hepatitis liver samples parvovirus was detected by nested PCR, and one of these was also detected by nested SPP. CONCLUSIONS: Hepatitis in dogs is not caused by agents with high homology to known infectious agents that cause hepatitis in other species.     

Tenascin-C in chronic canine hepatitis: immunohistochemical localization and correlation with necro-inflammatory activity, fibrotic stage, and expression of alpha-smooth muscle actin, cytokeratin 7, and CD3+ cells

During fibrosis, the extracellular matrix (ECM) is continuously remodeled and increases in volume due to the production of various proteins. We studied the distribution of tenascin-C (TN-C) and the correlation of TN-C with the necro-inflammatory activity and expression of alpha-smooth muscle actin (alpha-SMA), cytokeratin 7 (CK7), and CD3+ T-lymphocytes in canine chronic hepatitis. This was analyzed using immunohistochemistry and semiquantitative scoring. We used 3 groups (n = 19) of dogs: group 1 (n = 5) with neonatal hepatitis/lobular dissecting hepatitis (NH/LDH), group 2 (n = 8) with chronic hepatitis/cirrhosis (CH/CIRR), and group 3 (n = 6) consisting of healthy animals. In normal livers, TN-C was localized in Disse's space and around bile ducts and blood vessels. In CH/CIRR livers, TN-C was localized at the periphery of the regenerating nodules and was conspicuous in the bridging fibrous bands. In NH/LDH, TN-C was diffusely distributed along the reticular fibers that dissected between single cells or groups of hepatocytes. alpha-SMA in the normal hepatic parenchyma showed an irregular distribution along the perisinusoidal linings. In other groups, alpha-SMA was increased in fibrotic septa and perisinusoidal linings. In normal livers, CK7 was positive in bile ducts. In other groups, CK7-expressing cells were conspicuous in the portal-parenchymal interface, the periphery of the regenerative nodules, and the degenerated parenchyma. The pattern of CD3+ lymphocytes was inversely proportional to that of TN-C. These results also showed that TN-C is strongly correlated with increased fibrotic stage, inflammatory activity, and expression of CK7 and alpha-SMA. TN-C, CK7, and CD3 expression did not differ between diagnostic groups.     

血清3型鸭甲型肝炎病毒阳性血清的制备

通过使用血清3型鸭甲型肝炎疫苗免疫SPF鸡,制备了一批血清3型鸭甲型肝炎诊断用阳性血清,并对其进行了无菌、支原体和特异性检验以及中和效价测定。结果表明,该血清无菌检验合格,无支原体污染,特异性良好,无禽类常见13种外源病毒抗体,血清中和效价为10-2.8。本研究为鸭甲型肝炎病毒血清学鉴定及相关研究提供了重要的物质基础。     

Scintigraphic diagnosis of primary hepatocellular carcinoma in the woodchuck (Marmota monax)

Hepatic imaging with 99mTc-sulfur colloid was used to diagnose primary hepatocellular carcinoma (PHC) in woodchucks infected with woodchuck hepatitis virus (WHV). Based on imaging results, 6 of 12 WHV-infected woodchucks had space-occupying hepatic lesions, and all 6 had PHC. Of the remaining woodchucks, 2 did not have PHC, 2 had discrete tumors (less than 1 cm diameter), 1 had miliary small tumors, and 1 had tumors located near the great vessels. Hepatic imaging was a valuable technique for diagnosis of PHC in WHV-infected woodchucks.