Hepatic Fibrosis in Dogs

Hepatic fibrosis is commonly diagnosed in dogs, often as a sequela to chronic hepatitis (CH). The development of fibrosis is a crucial event in the progression of hepatic disease that is of prognostic value. The pathophysiology of hepatic fibrosis in human patients and rodent models has been studied extensively. Although less is known about this process in dogs, evidence suggests that fibrogenic mechanisms are similar between species and that activation of hepatic stellate cells is a key step. Diagnosis and staging of hepatic fibrosis in dogs requires histopathological examination of a liver biopsy specimen. However, performing a liver biopsy is invasive and assessment of fibrotic stage is complicated by the absence of a universally accepted staging scheme in veterinary medicine. Serum biomarkers that can discriminate among different fibrosis stages are used in human patients, but such markers must be more completely evaluated in dogs before clinical use. When successful treatment of its underlying cause is feasible, reversal of hepatic fibrosis has been shown to be possible in rodent models and human patients. Reversal of fibrosis has not been well documented in dogs, but successful treatment of CH is possible. In human medicine, better understanding of the pathomechanisms of hepatic fibrosis is leading to the development of novel treatment strategies. In time, these may be applied to dogs. This article comparatively reviews the pathogenesis of hepatic fibrosis, its diagnosis, and its treatment in dogs.     

Hepatic diseases in horses

The concept 'liver disease' includes several pathological conditions affecting liver's functions. It can either consist of a temporary impaired functioning of the liver and/or it can progress to its failure. The purpose of this review is to update the knowledge on hepatobiliary diseases and in particular on equine hyperlipaemia. Hepatobiliary disease's aetiology, clinical signs, diagnosis and nutritional management are thus described in the first part of the review the second part being devoted to hyperlypaemia's lipid metabolism, epidemiology, clinical signs, post-mortem observations and nutritional management. Diagnosis of hepatic disease is usually based on the assessment of the serum activities while hepatic biopsy is considered as the golden standard of diagnosis of hepatic function. Nutritional management is often very useful in management of hepatic diseases: diet should be low in protein (of good biological value) and high in non-structural carbohydrates except for chronic hepatic disease (slightly high protein). Equine hyperlipaemia's mortality is around 70%. It consists of a disorder of lipid metabolism, characterized by increase in plasma triglycerides and deposition of fat on organs. From a nutritional point of view, hyperlipaemia in horses can be approached by maintaining positive energy balance, fighting dehydration and metabolic acidosis, and by the use of lipotropic factors.     

火鸡肝脏脂肪沉积症

肝脏脂肪沉积症又称脂肪肝或肝脂肪变性,是一种会影响火鸡种用母鸡或肉火鸡的病理性疾病。这种疾病显然通常发生在健康火鸡上,其确切病因仍有待确定。     

Hepatic ultrasonography in the dog

Ultrasonography may be used to evaluate noninvasively a wide variety of diseases affecting the canine liver. Hepatic mass lesions, parenchymal pathology, gallbladder and biliary disease, and vascular abnormalities may be detected and characterized by ultrasonography. Ultrasonically guided percutaneous liver biopsy can improve the succes and safety of obtaining diagnostic cytologic material. The response of liver disorders to treatment may be effectively monitored by serial ultrasonographic examination. The ultrasonographic diagnosis of canine liver disease is described and illustrated with 11 case history reports.     

Hepatic encephalopathy

Hepatic encephalopathy is a neurometabolic syndrome caused by altered hepatic blood flow patterns and/or hepatic disease. This article describes current thoughts on its pathogenesis and diagnosis. Treatment principles are emphasized.     

Hepatic neoplasia

The clinicopathologic features of hepatic neoplasms such as hepatocellular adenomas, hepatocellular carcinomas, bile duct carcinomas, and hepatic carcinoids are presented. The authors also discuss the diagnostic and therapeutic approaches to hepatic neoplasia.     

Hepatic Encephalopathy

Hepatic encephalopathy occurs in a number of different species as a result of either congenital portacaval shunts or acquired liver disease. Despite intensive research, the neurochemical basis of the disorder has not been defined. Theories to explain the cerebral dysfunction that accompanies acute or chronic hepatic failure include 1) ammonia acting as the putative neurotoxin, 2) perturbed monoamine neurotransmission as a result of altered plasma amino acid metabolism, 3) an imbalance between excitatory amino acid neurotransmission, mediated by glutamate, and inhibitory amino acid neurotransmission, mediated by gamma-aminobutyric acid, and 4) increased cerebral concentrations of an endogenous benzodiazepine-like substance.     

Hepatic biopsy

Hepatic biopsy plays an integral part in the formation of the diagnosis, selection of the therapy, and determination of the prognosis in clinical cases of hepatic disease. It has been shown that results of hepatic biopsy correlate well with postmortem findings and findings of liver function tests. Hepatic biopsy is not difficult to perform and the benefits usually outweigh the risks and costs. The techniques described have many variations that are influenced by the experience and skill of the practitioner and the equipment available to the practitioner. It is the authors' opinion that, with the proper training, every practitioner can obtain hepatic biopsies and, thus, increase the quality of medical care to their patients.     

Hepatic abscesses in three horses

Hepatic abscesses were diagnosed in 3 adult horses. Two were < 4 years old and had evidence of concurrent immune-mediated conditions, including aseptic arthritis, immune-mediated thrombocytopenia, and immune-mediated anemia. Predisposing factors for hepatic abscess formation in these horses included prior abdominal surgery, proximal duodenitis/jejunitis, inflammatory bowel disease, and a penetrating foreign body in the large colon. Serum hepatic enzyme activities were within or slightly greater then reference limits in all 3 horses. The most pronounced and consistent abnormalities on CBC and serum biochemical analyses were hyperproteinemia, hyperglobulinemia, and a decreased albumin-to-globulin concentration ratio. Hepatic ultrasonography identified hepatic abscesses in all 3 horses. A variety of bacteria were isolated from these abscesses, including Staphylococus aureus and Bacteroides fragilis. One horse developed septic tibiotarsal arthritis, presumably as a result of intermittent bacteremia. Despite aggressive medical treatment, all horses were euthanatized because of a worsening condition and poor prognosis.     

Hepatic dearterialization in the dog

Hepatic dearterialization was performed in 9 adult dogs. Evaluation of the technique was based on clinical and laboratory assessment of physiologic and pathologic changes related to the procedure. All dogs had hematologic and histopathologic evidence of transient hepatic ischemia that was reflected by minimal post-operative morbidity.