Serum enzyme determination in the study of liver disease in dogs

Glutamate dehydrogenase (GLDH), sorbitol dehydrogenase (SDH), 5''-nucIeotidase (5''-ND) and cholin esterase (CHE) were determined in the sera of 37 dogs with various liver diseases. The values for these parameters were compared with the values for aspartate and alanin aminotransferase (ASAT, ALAT), alkaline phosphatase (ALP), γ-glutamyl transferase (γ-GT) and albumin (ALB). GLDH was found to be the most sensitive enzyme parameter (sensitivity 92 %), its values also reflecting the degree of liver cell necrosis well. Next in sensitivity followed ASAT and ALP. SDH values were correlated to ALAT values but had a low sensitivity (43 %). 5''-ND discriminated markedly better between biliary tract disturbance and other lesions than ALP and somewhat better than γ-GT. CHE had a wide reference range, low sensitivity, and was not correlated to ALB. Single determinations of CHE may thus not be of diagnostic value in dogs.     

Circulatory disorders of the liver in dogs and cats

Summary

This paper presents a review of the literature on hepatic circulation and circulatory disorders of the liver in the dog and cat, and also includes a number of our own not previously published data. Circulatory disorders of the liver are frequently observed in dogs and cats. These disorders can be divided into congenital portosystemic shunts, disorders associated with outflow disturbances, and disorders associated with portal hypertension. Outflow disturbances result in passive congestion of the liver and in both species are mainly due to cardiac failure. Portal hypertension with resultant portosystemic collateral circulation and ascites mainly results from chronic liver disease, particularly cirrhosis. The main vascular disorder resulting in portal hypertension and ascites in the dog is primary hypoplasia of the portal vein.     

Radiographic assessment of liver volume in dogs

In a group of 65 dogs, radiographic liver length, the length of the axis from the most cranial part of the diaphragm to the apex of the liver tip, was correlated significantly (P less than 0.000001) with real liver volume. Within this group, radiographic liver length, compared with the length of the eleventh thoracic vertebra, was correlated with liver volume per kilogram of body weight. In a group of 30 dogs, with histologically normal liver, this measurement was not affected by thoracic conformation. These findings suggest that radiographic liver length is a reliable measurement for estimating liver volume in dogs and that it is not influenced by thoracic conformation. For 60 of the 65 dogs, a method of assessment of liver volume was formulated that required 2 measurements to be made on the lateral abdominal radiograph and 1 to be made on the dog itself.     

Effects of long-term phenobarbital treatment on the liver in dogs

Long-term administration of phenobarbital has been reported to cause hepatic injury in dogs. Phenobarbital induces hepatic enzymes, and it may be difficult to distinguish the effect of enzyme induction on serum liver enzyme activities from actual hepatic damage. The hepatotoxicity of phenobarbital and the impact of enzyme induction on serum liver enzyme activity were investigated prospectively in 12 normal dogs. Phenobarbital was administered for 29 weeks at 5 mg per kilogram of body weight (range, 4.8— 6.6 mg/kg) PO q12h, resulting in therapeutic serum phenobarbital concentrations (20–40 μg/mL). Serum alkaline phosphatase (ALP), alanine transaminase (ALT), aspartate transaminase (AST), γ-glutamyltransferase (GGT), fasted bile acids (fBA), total bilirubin, and albumin were determined before and during treatment. Lateral abdominal radiographs, abdominal ultrasounds, and histopathologic examinations of liver tissue obtained by ultrasound-guided biopsy were performed before and during treatment. Radiographs revealed a moderate increase in liver size in most dogs. Ultrasonographic examination revealed no change in liver echogenicity or architecture. No evidence of morphologic liver damage was observed histopathologically. ALP and ALT increased significantly ( P < .05), GGT increased transiently, and albumin decreased transiently during the study. There were no significant changes in AST, bilirubin, and fBA. These results suggest that increases in serum ALP, ALT, and GGT may reflect enzyme induction rather than hepatic injury during phenobarbital treatment in dogs. Serum AST, fBA, and bilirubin, and ultrasonographic evaluation of the liver are not affected by the enzyme-inducing effect of phenobarbital and can therefore be helpful to assess liver disease in dogs treated with the drug.     

Management of liver disease in dogs and cats

Ampicillin or amoxicillin is a good initial choice for treatment of liver disease involving bacteria. Cephalosporins, among other antibiotics, can be used with aminoglycosides for a broad-spectrum effect. Metronidazole may benefit patients with hepatic encephalopathy. Tetracycline, penicillins and cephalosporins are good choices for biliary disease. Corticosteroids are indicated for chronic active hepatitis, cholangiohepatitis, immune-mediated hepatopathy, and hepatic lymphosarcoma and mast-cell tumors. D-penicillamine is used to treat hepatic Cu toxicosis. Colchicine has been used to combat hepatic fibrosis. Lactulose is used in long-term management of hepatic encephalopathy. Diuretics and a low-Na diet help control ascites. Cimetidine is used to control GI ulcers. Anabolic steroids help reverse protein catabolism. Acetylcysteine is an antidote for acetaminophen toxicity. Use of hetacillin, chloramphenicol, lincomycin, sulfonamides, erythromycin, acetaminophen and methyltestosterone should be avoided in patients with liver disease.     

Evaluation of serum L-phenylalanine concentration as indicator of liver disease in dogs: a pilot study

Because essential amino acids are metabolized in the liver, liver diseases may impair their catabolism. In this study, serum L-phenylalanine concentrations in 28 dogs with liver diseases were compared with those of 28 healthy dogs and 13 dogs with nonhepatic diseases. Dogs with liver diseases had significantly increased L-phenylalanine serum concentrations compared to healthy dogs (P<0.001) and to those with nonhepatic diseases (P<0.01). There were no significant differences among the L-phenylalanine serum concentrations of dogs with different degrees of liver diseases. The sensitivity and specificity of L-phenylalanine to fasting bile acids were comparable.     

Effects of different liver diseases on the platelet count in dogs

Changes of the platelet count in liver diseases are described in humans. Thrombocytopenia was observed more frequently than thrombocytosis. There are only a few investigations on platelet counts in liver diseases in dogs. The goal of the present study was to investigate the influence of different liver diseases including degeneration, hepatitis and liver tumours, on the platelet count. Platelet counts of 52 dogs with different liver diseases were measured and compared with 52 healthy dogs. The results showed, that dogs with liver degeneration have thrombocytosis in 41% of the cases and a group of dogs with liver tumours (malignant histiocytosis, hepatoma, malignant lymphoma anaplastic sarcoma, cholangiocarcinoma, hepatocellular carcinoma) had thrombocytopenia in 50% of the cases. The dogs with hepatitis showed no specific changes in the platelet count. The statistical comparison of our patients with liver disease and a control group of healthy dogs showed significantly higher platelet counts in cases of liver degeneration (p < 0.0001) and significantly lower platelet counts in cases of liver tumour (p < 0.001). The comparison between the dogs with different liver diseases showed significantly lower platelet counts in dogs with liver tumours when compared to dogs with liver degeneration (p < 0.0001). There was no significant difference between dogs with liver tumours and dogs with hepatitis and between dogs with liver degeneration and dogs with hepatitis. Based on the results of this study the author recommends to assess platelet counts in all dogs with liver disease, especially if liver biopsy is planed.     

Morphometric study of the tricuspid valve in dogs

An anatomical study of the tricuspid valve was performed in the hearts of 45 dogs using a method of dissection which preserves the integrity of the valve. Morphometrical criteria such as the width of the cusp base and larger depth of cusp and morphological criteria such as the number of tendinous cords, the perimeter of the fibrous ring and the properties of the papillary muscle were adopted for the characterization of a cusp. The tricuspid valve was not consistent with three cusps, but it was observed to present 2, 4 or 5 cusps in 68% of the cases.     

A procedure for the examination of the liver and pancreas in dogs

A technique is described for the visual examination and biopsy sampling of the affected organ in canine liver and pancreatic dysfunction.
Résumé . On a décrit une technique pour l'examen visuel et la biopsie d'essais de l'organe affecté dans le foie du chien et le mauvais fonctionnement du pancreas.
Zusammenfassung . Man hat eine Technik beschrieben, für die Sichtprobe und die Biopsie-Probenahme des angegriffenen Organs in der Hundeleber und in der Bauchspeichelschlechtfunktion.     

Circulating autoantibodies in dogs with chronic liver disease

Circulating autoantibodies are important diagnostic markers in human liver disease. Antinuclear antibodies, smooth muscle antibodies and liver membrane antibodies are characteristic of human autoimmune chronic active hepatitis, while antimitochondrial antibodies are most frequently found in primary biliary cirrhosis. The role of these autoantibodies in the pathogenesis and course of these diseases is not known, but they are routinely measured in order to discriminate between different liver diseases. This, in turn, helps to predict the response to different kinds of treatment. The present study reports the occurrence of circulating autoantibodies in sera of dogs with different forms of chronic hepatitis and cirrhosis, and in dogs with other liver diseases, such as acute hepatitis, liver degeneration and tumours. The results indicate several differences compared to the autoantibody patterns in human liver disease.     

Serum gastrin concentrations in dogs with liver disorders

Dogs with liver disorders often display gastrointestinal signs that may be triggered by ulceration. The liver is important for inactivation of some forms of gastrin. Therefore, hypergastrinaemia has been implicated in the pathogenesis of gastrointestinal ulcerations related to liver dysfunction. The aim of this study was to determine serum gastrin concentrations in dogs with liver disease. Fasted blood samples were collected from 15 dogs with newly diagnosed liver disease and 18 healthy dogs. Gastrin concentrations were significantly lower in dogs with congenital portosystemic shunt compared with healthy dogs (P=0.003). No significant difference (P=0.6) in gastrin concentration was revealed between dogs with hepatocellular disease and healthy dogs. Serum gastrin concentrations were not significantly associated with the occurrence of vomiting, anorexia, diarrhoea, or melaena in dogs with liver disorders. These findings did not provide support for the role of hypergastrinaemia in the development of gastrointestinal signs associated with liver disease in dogs. Decreased serum concentrations of gastrin in a dog with liver disease may suggest the presence of portosystemic shunt. Further investigation is warranted to determine the importance of hyopogastrinaemia in congenital postosystemic shunts in dogs and to evaluate potential alterations in serum gastrin concentrations in specific hepatocellular diseases.     

Bacteriological status of canine milk and septicaemia in neonatal puppies--a retrospective study

Results of the bacteriological examination of milk samples from 46 bitches were evaluated retrospectively, and correlated with findings of the bacteriological examination of organs from dead, septicaemic puppies in their litters (n = 33). The aim of this study was to investigate, in how many cases of clinical and subclinical mastitis of the bitches, the same bacteria can be detected in their septicaemic neonates. One group of lactating bitches was clinically healthy (group I, n = 38), whereas in eight bitches different puerperal disorders were found (group II). Twenty-five septicaemic puppies were from group I, eight from group II. Out of a broad spectrum of bacteria isolated from the milk of clinically healthy and diseased bitches, only Escherichia coli, Klebsiella pneumoniae and/or ss-haemolytic (haem.) Streptococcus sp. could be isolated from organs of their septicaemic puppies. This was the case in three bitches with mastitis and in one clinically healthy bitch only. Staphylococcus intermedius, although frequently isolated from canine milk, does not seem to be a cause of septicaemia in neonates. It is assumed that in most cases of neonate septicaemia, bacteria from the bitches' milk are not the primary cause.     

The influence of age on the cytology of the liver in healthy dogs

Liver cytology was evaluated in 28 healthy dogs 1-14 years of age with normal liver structure and function. Smears were stained with May-Grünwald-Giemsa. Hepatocytes had distinct cell borders, and cells did not overlap. Cells with two nuclei and cells with intranuclear crystalloid structures were observed regularly. Cytoplasm contained small numbers of vacuoles characteristic of glycogen and lipid and small amounts of pigment consistent with ceroid or bile. Nuclei were uniform. Small numbers of biliary epithelial cells were seen in most samples. Lymphocytes and neutrophils occurred in small numbers, with lipocytes, mast cells, fibrocytes, mesothelial cells, eosinophils, and Kupffer macrophages seen less frequently. Mean parenchymal cell sizes were significantly greater in older dogs, but no age-related differences were observed in nuclear size. Older dogs also had a significantly increased number of nuclei per cell. There were more neutrophils in young and old dogs than in middle-aged dogs.     

Breed, sex and age distribution in dogs with chronic liver disease: a demographic study

Breed, sex and age distribution were studied in dogs with histopathologically diagnosed chronic (active or progressive) hepatitis and liver cirrhosis in Sweden. The study was based on clinical and histopathological records obtained during three years from a histopathological laboratory and during six years from an animal hospital. Some breeds were significantly (P<0–001) over-represented: American and English cocker spaniels, labrador retrievers and West Highland white terriers. In both spaniel breeds the males were most frequent whereas in the labrador retriever, the females were over represented. In the West Highland white terrier there was no sex difference. The average age at presentation was approximately five years in spaniels and West Highland white terriers and seven years in labrador retrievers. The high incidence of chronic liver disease and liver cirrhosis in certain breeds indicate that hereditary factors may be of importance in the development of chronic hepatitis and liver cirrhosis.