WSAVA Standards for Clinical and Histological Diagnosis of Canine and Feline Liver Diseases - eBook

This eBook is made for use in veterinary practice and for pathologists as an aid in making and understanding the diagnosis of all liver diseases of dogs and cats which are known to date. It is also meant to be a guide for the veterinary profession in the standardized diagnostic approach and nomenclature of liver diseases.

Members of The Society of Comparative Hepatology (SCH) have full access to this valuable source.

PREFACE AND ACKNOWLEDGEMENTS

This is the first world standard for the definition and nomenclature of diseases in small animal medicine, and the authors hope this joint international initiative will be the start of many comparable efforts to bring veterinarians over the world to consensus.

Chapter 1

Introduction - background, aims and methods

 Jan Rothuizen

This book is made for use in veterinary practice and for pathologists as an aid in making and understanding the diagnosis of all liver diseases of dogs and cats which are known to date. It is also meant to be a guide for the veterinary profession in the standardized diagnostic approach and nomenclature of liver diseases.

Chapter 2

 Sampling and handling of liver tissue  

 Jan Rothuizen, Valeer J. Desmet, Ted S.G.A.M. van den Ingh, David C. Twedt, Susan E. Bunch, Robert J. Washabau

 The diagnosis of most liver diseases depends essentially on histopathological examination of liver tissue. This is especially the case for parenchymal liver diseases, many biliary tract diseases, and tumors of the liver or biliary tract. The diagnosis of circulatory liver diseases depends largely on combined information obtained with laboratory examination, ultrasonography, and histopathological evaluation. The clinician has to combine the parts of the puzzle to make the diagnosis. To date, ultrasonography plays the central role in diagnosis of most circulatory liver diseases.

Chapter 3

Ultrasonographic identification and characterization of congenital portosystemic shunts and portal hypertensive disorders in dogs and cats  

Viktor Szatmári, Jan Rothuizen

In the first part of this chapter the hemodynamic, anatomic and pathophysiologic features of canine portal vein disorders are described. Understanding these principles is necessary for correct interpretation of the ultrasonographic images. In the second part of the chapter an ultrasonographic scanning protocol is described, which is recommended to be used for thorough evaluation of the portal venous system. A short section at the very end will discuss the specific features of feline portal vein disorders.

Chapter 4

Morphological classification of circulatory disorders of the canine and feline liver  

Chapter 5

Morphological classification of biliary disorders of the canine and feline liver  

Jenny A. Charles,  John M. Cullen, Valeer J. Desmet, Ted S.G.A.M. van den Ingh and Tom van Winkle.

The anatomy of the biliary system and the classification and morphology of the various biliary disorders in dogs and cats is presented. The biliary disorders can be grouped into four major categories: 1) biliary cystic disease and biliary atresia, 2) cholestasis and cholatestasis, 3) cholangitis and 4) diseases of the gall bladder. Histological examination of liver biopsies can substantially aid in the diagnosis of the first three categories. Changes in the portal tracts are the hallmarks of most of these biliary disorders. However, portal inflammation, fibrosis and bile duct proliferation are not restricted to biliary disorders and may  also be seen in primary parenchymal disorders such as acute and chronic hepatitis, and primary vascular abnormalities. Differentiation in general is possible through careful histological examination and evaluation of the combination of the parenchymal, vascular and portal tract lesions present in the affected liver. In contrast to the parenchymal and neoplastic liver diseases the diagnosis of diseases of the biliary tract depends not only on histopathological evaluation, but largely on ultrasonography. In neutrophilic cholangitis and cholecystitis culture and cytological examination of bile is required to assess the diagnosis. The role of the different diagnostic methods is summarized by the end of this chapter.

Chapter 6

Morphological classification of parenchymal disorders of the canine and feline liver - 1  

 Jenny A. Charles,  John M. Cullen, Valeer J. Desmet, Ted S.G.A.M. van den Ingh, Tom van Winkle.

The normal histology of the smallest liver unit and  the normal features of its constituting components are described to recognize the various parenchymal disorders and to understand the terminologies used. The parenchymal disorders can be grouped into seven categories: 1) reversible hepatocellular injury:  cell swelling, steroid induced hepatopathy and steatosis, and  2)  hepatic amyloidosis (this chapter), 3) hepatocellular death: apoptosis and necrosis, and  4) acute and chronic hepatitis and cirrhosis (Chapter 7), 5) hepatic abscesses and granulomas, 6) hepatic metabolic storage diseases and 7) miscellaneous conditions (Chapter 8).

Chapter 7

Morphological classification of parenchymal disorders of the canine and feline liver - 2  

Jenny A. Charles,  John M. Cullen, Valeer J. Desmet, Ted S.G.A.M. van den Ingh, Tom van Winkle

This chapter presents the various forms of hepatocellular death:  apoptosis and necrosis, the morphological patterns of necrosis in the liver, and the response of the liver to hepatocellular injury. The definition and characteristics of acute and chronic hepatitis and cirrhosis are given, including copper associated chronic hepatitis, lobular dissecting hepatitis and cirrhosis associated with superficial necrolytic dermatitis. Moreover, examples of specific infectious and non-infectious causes of hepatocellular necrosis  and hepatitis are given. Finally, the lesions and clinical significance of non-specific reactive hepatitis and eosinophilic hepatitis are presented.

Chapter 8

Morphological classification of parenchymal disorders of the canine and feline liver - 3  

Jenny A. Charles,  John M. Cullen, Valeer J. Desmet, Ted S.G.A.M. van den Ingh, Tom van Winkle

Hepatic abscesses and granulomas usually occur by haematogenic spread from the portal vein or in neonates from the umbilical vein and a wide variety of causative organism is given. The various hepatic metabolic storage diseases in dogs and cats mentioned in the literature are summarized including the enzymatic defect, the hepatic cells involved and their morphological  aspect. Finally, miscellaneous conditions are presented  including cytoplasmic and nuclear alterations in hepatocytes, Kupffer cells and hepatic stellate cells as well as extramedullary haemopoiesis.

Chapter 9

Morphological classification of neoplastic disorders of the liver in dogs and cats  

Jenny A. Charles,  John M. Cullen, Valeer J. Desmet, Ted S.G.A.M. van den Ingh, Tom van Winkle.

The neoplastic disorders of the liver in dogs and cats can be classified as 1) hepatocellular neoplasia, including nodular hyperplasia, 2) cholangiocellular neoplasia, 3) hepatic carcinoids and hepatoblastoma, 4) primary vascular and mesenchymal neoplasia, 5) haemotopoietic neoplasia, and 6) metastatic neoplasia.