Difference between revisions of "Hepatitis - Birds"
(Created page with "==Introduction== Hepatitis refers to '''inflammation of the liver''' which can lead to gross lesions visible at necropsy. In birds, these lesions are seldom diagnostic, as nume...") |
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==Viral Infections== | ==Viral Infections== | ||
− | + | <u>'''Psittaciformes'''</u> | |
− | '''Pacheco's disease''' caused by a herpesvirus | + | :'''Pacheco's disease''' caused by a herpesvirus |
+ | :'''[[Polyomavirus|Avian polyomavirus]]''' | ||
+ | :'''Acute [[Psittacine Beak and Feather Disease]]''' | ||
+ | :'''[[Avian Adenoviruses|Adenovirus inclusion body hepatitis]]''' | ||
+ | :'''[[Avian Orthoreovirus|Reovirus-associated hepatitis]]''' | ||
− | '''[[ | + | <u>'''Falconiformes'''</u> |
+ | :'''[[Avian Adenoviruses|Inclusion Body Hepatitis]]''' | ||
− | ''' | + | <u>'''Columbiformes, Strigiformes and others'''</u> |
+ | :'''Herpesvirus''' | ||
− | ''' | + | <u>'''Anseriformes'''</u> |
+ | '''[[Derzsy's Disease|Goose Virus Hepatitis]]''' | ||
− | ''' | + | <u>'''Galliformes'''</u> |
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− | ''' | ||
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'''[[Mareks Disease]]''' | '''[[Mareks Disease]]''' | ||
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===Gram-positive=== | ===Gram-positive=== | ||
− | ''Staphylococcus'' and ''Streptococcus'' species are the most common organisms isolated. They '''disseminate through the blood''' from chronic necrotising skin lesions or can reach the liver by extension from adjacent air sacs. | + | ''[[:Category:Staphylococcus species|Staphylococcus]]'' and ''[[:Category:Streptococcus species|Streptococcus]]'' species are the most common organisms isolated. They '''disseminate through the blood''' from chronic necrotising skin lesions or can reach the liver by extension from adjacent [[Avian Respiration - Anatomy & Physiology#Air Sacs|air sacs]]. |
− | ''Clostridia'' are of intestinal origin and can cause hepatitis. | + | ''[[:Category:Clostridium species|Clostridia]]'' are of intestinal origin and can cause hepatitis. |
− | ''Listeria monocytogenes'' can also cause disease, although it is a rare pathogen of birds. | + | ''[[Listeria monocytogenes]]'' can also cause disease, although it is a rare pathogen of birds. |
===Gram-negative=== | ===Gram-negative=== | ||
These are the most common causes of systemic bacterial infection. | These are the most common causes of systemic bacterial infection. | ||
− | '''Members of the Enterobacteriaceae''', including ''E. coli'', ''Klebsiella'', ''Proteus'', ''Salmonella'', ''Yersinia'' and ''Enterobacter'' are common isolates. | + | '''Members of the [[:Category:Enterobacteriaceae|Enterobacteriaceae]]''', including ''[[E. coli]]'', ''[[Klebsiella]]'', ''[[Proteus]]'', ''[[Salmonella]]'', ''[[Yersinia]]'' and ''Enterobacter'' are common isolates. |
This is usually secondary to invasion from the gut or extension up the biliary tree. | This is usually secondary to invasion from the gut or extension up the biliary tree. | ||
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==Parasites== | ==Parasites== | ||
− | + | '''Apicomplexa''': ''[[Toxoplasma gondii]]'' and ''[[Sarcocystis]]'' | |
− | ''[[Toxoplasma gondii]]'' | ||
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− | ''[[Sarcocystis]] | ||
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− | + | '''Hemoprotozoa''': ''[[Plasmodium]]'', ''[[Leukocytozoon]]'' and ''Hemoproteus'' | |
− | ''[[ | ||
− | ''[[Histomonas|Histomonas meleagridis]]'' which is predominantly a disease of turkeys. | + | '''Sarcomastigophora''': ''[[Trichomonosis - Birds|Trichomonas gallinae]]'' infections which become generalised, ''[[Histomonas|Histomonas meleagridis]]'' which is predominantly a disease of turkeys. |
− | + | '''Microspora''': ''Encephalitozoon hellem'' | |
− | ''Encephalitozoon hellem'' | ||
==Toxic Hepatitis== | ==Toxic Hepatitis== | ||
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==Idiopathic== | ==Idiopathic== | ||
− | '''Chronic-active hepatitis''', or cirrhosis, is common in psittacine birds, particularly parrots, cockatiels, mackaws and budgerigars. The cause of the hepatitis cannot be determined due to the chronicity of the lesions. | + | '''Chronic-active hepatitis''', or [[cirrhosis]], is common in psittacine birds, particularly parrots, cockatiels, mackaws and budgerigars. The cause of the hepatitis cannot be determined due to the chronicity of the lesions. |
{{Learning | {{Learning | ||
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− | [[Category: | + | {{review}} |
− | [[Category: | + | [[Category:Alimentary Diseases - Birds]] |
+ | [[Category:Expert Review - Birds]] |
Revision as of 14:11, 1 September 2011
Introduction
Hepatitis refers to inflammation of the liver which can lead to gross lesions visible at necropsy.
In birds, these lesions are seldom diagnostic, as numerous infectious diseases cause hepatitis. Liver inflammation usually occurs alongside systemic infection and changes in other organs such as the spleen and lungs may be helpful in obtaining a diagnosis.
Histopathology can usually be more revealing, especially if special stains are used. Electron microscopy, viral isolation, DNA probes and special cultures can be used to get an exact aetiological diagnosis.
Most causes of hepatitis are difficult to diagnose in the live bird, unless the enlarged liver causes abdominal distension or biochemical tests produce significant results.
Common causes of hepatitis are as follows:
Viral Infections
Psittaciformes
- Pacheco's disease caused by a herpesvirus
- Avian polyomavirus
- Acute Psittacine Beak and Feather Disease
- Adenovirus inclusion body hepatitis
- Reovirus-associated hepatitis
Falconiformes
Columbiformes, Strigiformes and others
- Herpesvirus
Anseriformes Goose Virus Hepatitis
Galliformes Mareks Disease
Bacterial Infections
Gram-positive and gram-negative bacteria can cause liver disease, usually secondary to septicaemia or enteritis.
Gram-positive
Staphylococcus and Streptococcus species are the most common organisms isolated. They disseminate through the blood from chronic necrotising skin lesions or can reach the liver by extension from adjacent air sacs.
Clostridia are of intestinal origin and can cause hepatitis.
Listeria monocytogenes can also cause disease, although it is a rare pathogen of birds.
Gram-negative
These are the most common causes of systemic bacterial infection.
Members of the Enterobacteriaceae, including E. coli, Klebsiella, Proteus, Salmonella, Yersinia and Enterobacter are common isolates.
This is usually secondary to invasion from the gut or extension up the biliary tree.
Mycobacteria
M. avium infects all birds.
Intracellular bacteria
Chlamydophila psittaci causes psittacosis and hepatomegaly with yellow foci of necrosis.
Fungal Infections
This is usually from extension from the lungs or air sacs, or as a result of haematologic spread.
Aspergillus species most commonly affect the liver.
Systemic Candida infection, particularly in immunosuppressed birds, can also result in liver invasion.
Parasites
Apicomplexa: Toxoplasma gondii and Sarcocystis
Hemoprotozoa: Plasmodium, Leukocytozoon and Hemoproteus
Sarcomastigophora: Trichomonas gallinae infections which become generalised, Histomonas meleagridis which is predominantly a disease of turkeys.
Microspora: Encephalitozoon hellem
Toxic Hepatitis
Ingestion of heavy metals such as lead or zinc.
Vitamin D toxicity
Mycotoxins such as Aflatoxins
Idiopathic
Chronic-active hepatitis, or cirrhosis, is common in psittacine birds, particularly parrots, cockatiels, mackaws and budgerigars. The cause of the hepatitis cannot be determined due to the chronicity of the lesions.
Hepatitis - Birds Learning Resources | |
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Flashcards Test your knowledge using flashcard type questions |
Avian Medicine Q&A 11 |
References
Samour, J. (2000) Avian Medicine Elsevier Health Sciences
Schmidt, R. (2003) Pathology of pet and aviary birds Wiley-Blackwell
Doneley, R. (2010) Avian medicine and surgery in practice Manson Publishing
This article has been peer reviewed but is awaiting expert review. If you would like to help with this, please see more information about expert reviewing. |