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| | + | {{frontpage |
| | + | |pagetitle =Enteritis, Fibrinous/Haemorrhagic |
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| | + | <categorytree mode=pages>Enteritis, Fibrinous/Haemorrhagic</categorytree> |
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| | + | </b></big> |
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| | ==Pathology== | | ==Pathology== |
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| | * The mucosa eroded to produce lesions of darkish-red submucosa covered in dry, crumbly fibrin. | | * The mucosa eroded to produce lesions of darkish-red submucosa covered in dry, crumbly fibrin. |
| | * Is usually caused by severe damage due to secondary bacterial infection following an earlier milder insult. | | * Is usually caused by severe damage due to secondary bacterial infection following an earlier milder insult. |
| − | * Tends to be more severe in the lower [[Small Intestine - Anatomy & Physiology|small intestine]] and upper [[Large Intestine - Anatomy & Physiology|large intestine]]. | + | * Tends to be more severe in the lower [[Small Intestine Overview - Anatomy & Physiology|small intestine]] and upper [[Large Intestine - Anatomy & Physiology|large intestine]]. |
| | ** Many severe infections tend to get worse further down the gut. | | ** Many severe infections tend to get worse further down the gut. |
| − | *** Catarrhal change may be seen in the upper [[Small Intestine - Anatomy & Physiology|small intestine]] and fibrinous change in the lower [[Small Intestine - Anatomy & Physiology|small intestine]]s. | + | *** Catarrhal change may be seen in the upper [[Small Intestine Overview - Anatomy & Physiology|small intestine]] and fibrinous change in the lower [[Small Intestine Overview - Anatomy & Physiology|small intestine]]s. |
| | ** In the lower aprt of the bowel, where the inflammation is more severe, disease is more anaerobic. | | ** In the lower aprt of the bowel, where the inflammation is more severe, disease is more anaerobic. |
| | *** Lesions are caused by anaerobic organisms- convert mild diseases into more serious disease. | | *** Lesions are caused by anaerobic organisms- convert mild diseases into more serious disease. |
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| − | ==[[Salmonellosis]]==
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| − | ==Swine Dysentery==
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| − | * Swine dysentery gives rise to fibrinous/ haemorrhagic enteritis.
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| − | * A quite common and important disease.
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| − | * The disease is caused by [[Brachyspira hyodysenteriae|''Brachyspira hyodysenteriae'']].
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| − | ** Is not seen in gnotobiotic animals - other enteric pathogens such as [[Fusobacterium|''Fusobacterium'']] or [[Bacteroides|''Bacteroides'']] may therefore also be required in order to produce disease.
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| − | * The disease is NOT systemic.
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| − | ** Localised to the [[Large Intestine - Anatomy & Physiology|large intestine]]- in particular, the spiral [[Colon - Anatomy & Physiology|colon]].
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| − | * Swine dysentery is spread by the faeco-oral route, and is carried by pigs and rodents.
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| − | ===Clinical===
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| − | * Affects post weaning pigs at approximately 4 months of age.
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| − | * White scour becomes a liquid dirty red / brown scour with a foul smell.
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| − | ** Contains poorly digested focal shreds of mucosa and fibrin strands.
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| − | *** '''Mucoid covered faeces'''.
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| − | * There are three outcomes to infection; the animal may:
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| − | ** Die
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| − | ** There is a morbidity up to 90% in the herd, with up to 50% mortality.
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| − | ** Recover
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| − | ** Become chronically infected.
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| − | * Symptoms are due to loss of absorption in [[Colon - Anatomy & Physiology|colon]].
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| − | ** The [[Colon - Anatomy & Physiology|colon]] is normally a key site of absorption for water and electrolytes in the pig.
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| − | ===Pathology===
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| − |
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| − | * The serosa of the spiral [[Colon - Anatomy & Physiology|colon]] may appear shiny from the outside.
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| − | ** Is turgid and oedematous.
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| − | ** In severe cases, haemorrhage may be seen.
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| − | * The [[Small Intestine - Anatomy & Physiology|small intestine]] NOT affected.
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| − | * Fibrinous deposits are seen on the mucosa as the disease progresses.
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| − | ** The mucosa underneath is eroded to expose blood vessels in lamina propria.
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| − | *** Accounts for the bleeding.
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| − | * Animals often recover, but have a low feed conversion ratio for sometime.
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| − | ===Diagnosis===
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| − | * Silver stains show organisms in the epithelium of the mucosa.
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| − | * Also by immunofluorescence or electron microscopy.
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| − | ==Parvovirus Enteritis==
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| − | * [[Parvoviridae|Parvovirus]] enteritis is also know as feline infectious enteritis or feline panleucopenia
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| − | * Since a vaccine is available, this disease is now uncommon.
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| − | * Over the last 10/15 years this has been seen primarily in the cat, but it is now also seen [[Intestine Inflammatory - Pathology#Canine Disease|in the dog]].
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| − | ===Clinical===
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| − | * Manifests mainly in cats under 6 months old.
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| − | * Common in groups of unvaccinated cats.
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| − | ** Produces big outbreaks, with [[Control of Feeding - Anatomy & Physiology#The Vomit Reflex|vomiting]] and pyrexia.
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| − | * Severe [[Control of Feeding - Anatomy & Physiology#The Vomit Reflex|vomiting]] and [[Intestine Diarrhoea - Pathology|diarrhoea]] occur.
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| − | ** [[Intestine Diarrhoea - Pathology|diarrhoea]] is thin, watery and foul-smelling, and may also be blood-tinged.
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| − | *** Animals usually die despite treatment- die from dehydration.
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| − | * Animals suffer from fever.
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| − | * Pancytopaenia also occures.
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| − | ** White blood cell count drops very low so as to become almost non-existent.
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| − | *** Drops to 1/ml from 10000/ml.
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| − | ** Animals may therefore also die from other infections.
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| − | ===Pathology===
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| − | ====Gross====
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| − | * Virus targets crypt cells and lymphoid areas.
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| − | ** Causes [[Intestine Inflammatory - Pathology#Villus Atrophy|villus atrophy]].
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| − | * In the cat, the intestine is thickened, turgid and swollen.
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| − | ** Has a pale, dull and mottled appearance.
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| − | ** The contents are rather dry - this gets worse lower down the gut.
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| − | * Areas of depression in the mucosa can be seen in the upper small bowel.
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| − | ** Due to necrosis of tissue overlying Peyers patch.
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| − | * Lower down in the gut, enteritis is apparent.
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| − | ** Cat- fibrinous.
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| − | ** Dog- haemorrhagic.
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| − | *** Blood in lumen.
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| − | ** Inflammation sometimes doesn't appear very severe.
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| − | * There may be very few lesions
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| − | ** Histology is usually required for diagnosis.
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| − | * A '''radiomimetic virus'''.
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| − | ** Affects all rapidly dividing cells and destroys them.
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| − | *** E.g. epithelium in the base of the crypts of [[Small Intestine - Anatomy & Physiology|small intestine]] are killed.
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| − |
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| − | ====Histological====
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| − | * The crypt lining cells undergo complete necrosis, but very little inflammation occurs.
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| − | ** Collapse of villous architecture.
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| − | * May be fibrinous exudates on surface of mucosa.
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| − | * The submucosa and lamina propria are not affected and are left intact.
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| − | ** Many [[Neutrophils - WikiBlood|neutrophils]] in the lamina propria.
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| − | * Cyst-like structures are seen in the deepest parts of the glands of the intestinal mucosa, if the animal survives for more than a few days.
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| − | ** Flattened epithelial cells line these cystic glands.
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| − | *** Are enterocytes trying to repair the damage.
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| − | *** However, animals usually die from dehydration or secondary infection before the mucosa recovers.
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| − | * Inclusion bodies may be seen, but these are very hard to find.
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| − | * May get [[Lymphocytes - WikiBlood|lymphocyte]] invasion of mucosa.
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| − | * [[Lymph Nodes - Anatomy & Physiology|Lymph nodes]] appear pale and oedematous, and almost aplastic.
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| − | * [[Bone Marrow - Anatomy & Physiology|Bone marrow]] appears pale and fatty looking and is depleted of cells.
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| − | ===Canine Disease===
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| − | * Until 1978 Parvovirus enteriris was totally unknown in dogs.
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| − | * First seen in dogs in Australia.
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| − | ** Apeared very similar but perhaps slightly worse than the disease seen in the cat.
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| − | ** A new and distinct disease, but the virus is very closely related to the feline virus.
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| − | *** Viral DNA is 98% homologous to the feline virus.
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| − | ** The canine virus does NOT cause disease in cats.
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| − | * '''Clinical'''
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| − | ** Causes enteritis in young dogs over 6 weeks old.
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| − | ** Causes myocarditis in puppies.
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| − | ** Mainly affects the [[Small Intestine - Anatomy & Physiology|small intestine]].
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| − | * Vaccines are very effective, but the virus is hardy and survives in the environment.
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| − | * Diagnosis:
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| − | ** Look for viral antigen in the faeces by the red cell agglutination test.
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| − | ** Immunoflurescence.
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| − | ** ELISA.
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| − | ** Serology.
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| − | ==Bacterial septicaemia and enteritis==
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| − | * Some severe acute septicaemias cause very severe acute haemorrhagic enteritis with bleeding into the [[Alimentary - Anatomy & Physiology|alimentary tract]].
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| − | * Death is usually rapid.
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| − | * Fairly easy to diagnose
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| − | ** [[Small Intestine - Anatomy & Physiology|small intestine]] is full of dark, tarry, partly clotted blood (like black currant jelly).
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| − | * Associated with severe systemic disease, e.g.
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| − | ** '''Anthrax''' in cattle ([[Bacillus anthracis|''Bacillus anthracis'']]).
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| − | ** '''Leptospirosis''' in dogs.
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| − | *** Especially [[Leptospira|''L. icterohaemorrhagiae'']].
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| − | * Do not confuse with [[Warfarin Poisoning|warfarin poisoning]].
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| − | ** Also gives blood in [[Forestomach - Anatomy & Physiology|stomach]] and intestine BUT there are no signs of inflammatory disease.
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| − | ===Lamb Dysentery (Enterotoxaemia with Blood)===
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| − | * [[:Category:Enteropathogenic and Enterotoxaemic Clostridia|''Clostridium perfringens'']] causes very severe acute haemorrhagic enteritis.
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| − | ** Usually affects young farm animals
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| − | *** May also be seen in pets.
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| − | * Type B [[:Category:Enteropathogenic and Enterotoxaemic Clostridia|''Clostridium perfringens'']] infection of lambs leads to '''lamb dysentery'''.
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| − |
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| − | ====Clinical====
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| − | * Lamb dysentery is usually seen in lambs under 2 weeks of age.
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| − | ** Related to being kept in a cold, dirty environment, with build-up of infection during the lambing season.
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| − | * Lambs may produce bloodstained [[Intestine Diarrhoea - Pathology|diarrhoea]] before death, but they often die before this effect is apparent.
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| − | * Diagnosed by culturing contents of gut.
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| − |
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| − | ====Pathology====
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| − | =====Gross=====
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| − | * The gut is blown and distended with foamy ,bloody contents.
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| − | * Sometimes ulceration with perforation and fibrinousperitonitis is seen.
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| − | * Focal or diffuse congestion and haemorrhages.
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| − |
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| − | =====Histological=====
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| − | *Coagulative necrosis of villi.
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| − | * Oedema.
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| − | * Haemorrhage.
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| − | * Influx of inflammatory cells in the lamina propria and submucosa.
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| − | ====Similar Conditions====
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| − | * '''Piglets''' show similar disease caused by [[:Category:Enteropathogenic and Enterotoxaemic Clostridia|''Clostridium perfringens'']] type C (and sometimes type B)
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| − | ** May look similar to a volvulus but with no twist present.
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| − | * In '''adult sheep''' [[:Category:Enteropathogenic and Enterotoxaemic Clostridia|''Clostridium perfringens'']] type B infection causes '''Struck'''.
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| − | ** Enterotoxigenic gastritis.
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| − | ** Acute sudden death with haemorrhagic enteritis
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| − | ** Haemorrhagic enteritis is not as severe as in lambs, and tends to be more patchy.
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| − | ===Colitis X===
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| − | * Affects the horse.
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| − | * Sudden onset with haemorrhages throughout body (shock) and sometimes acute foul smelling diarhoea.
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| − | * [[Colon - Anatomy & Physiology|colon]] is acutely haemorhagic and oedematous with mucosal necrosis.
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| − | * Associated with [[:Category:Enteropathogenic and Enterotoxaemic Clostridia|''Clostridium perfringens'']].
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| − | * Possibly an enterotoxaemia.
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| | [[Category:Intestine_-_Inflammatory_Pathology_by_Type]] | | [[Category:Intestine_-_Inflammatory_Pathology_by_Type]] |
