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==Introduction==
 
==Introduction==
Endocarditis is defined as an inflammation of the cardiac endocardium. The infection can affect the valves (valvular endocarditis) and then spread to the heart wall (mural endocarditis). It is usually a result of a bacteraemia or pyaemia, spread from adjaent myocardium is rare. It occurs in all species and is more common in cattle, pigs and sheep than dogs and cats.   
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[[Image:Bacterial endocarditis.jpg|right|thumb|200px|<small><center>'''Bacterial endocarditis'''. Courtesy of A. Jefferies</center></small>]]
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Endocarditis is defined as an inflammation of the cardiac endocardium. The infection can affect the valves (valvular endocarditis) and then spread to the heart wall (mural endocarditis). It is usually a result of a bacteraemia or pyaemia, spread from adjacent myocardium is rare. It occurs in all species and is more common in cattle, pigs and sheep than dogs and cats.   
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[[Image:Bacterial endocarditis.jpg|right|thumb|125px|<small><center>'''Bacterial endocarditis'''. Courtesy of A. Jefferies</center></small>]]
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Organisms commonly isolated include:
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*Cattle: ''[[Actinomyces pyogenes]]''
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*Pigs: [[Erysipelothrix_rhusiopathiae|''Erysipelothrix spp.'']]
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*Sheep: [[:Category:Streptococcus species|''Streptococci'']]
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Organisms commonly isolated include:
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*Cattle: [[Actinomyces pyogenes]]
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*Pigs: [[Erysipelothrix_rhusiopathiae|Erysipelothrix spp.]]
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*Sheep: [[:Category:Streptococcus species|Streptococci.]]
   
==Pathophysiology==
 
==Pathophysiology==
 
===Vegetative Endocarditis===
 
===Vegetative Endocarditis===
Predisposed by valvular damage as thrombi occur on the surface of the valves exposed to blood flow. Bacteremia is essential for the development of endocarditis.  Once bacteria colonize the valvular endocardium, vegetative lesions composed of platelets and fibrin are formed on the valves. Progression to rupture of the chordae tendinae is possible, along with spread of the infection to the adjacent mural endocardium. Valves may become stenotic, incompetant or both. Death usually results from either embolisation of the vegetative material or congestive heart failure due to significant valvular damage.
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[[Image:vegetative endocarditis.jpg|right|thumb|200px|<small><center>'''Vegetative endocarditis (dog)'''. Courtesy of T. Scase</center></small>]]
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It is predisposed by valvular damage as thrombi occur on the surface of the valves exposed to blood flow. Bacteremia is essential for the development of endocarditis.  Once bacteria colonize the valvular endocardium, vegetative lesions composed of platelets and fibrin are formed on the valves. Progression to rupture of the ''chordae tendinae'' is possible, along with spread of the infection to the adjacent mural endocardium. Valves may become stenotic, incompetent or both. Death usually results from either embolisation of the vegetative material or congestive heart failure due to significant valvular damage.
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===Ulcerative Endocarditis===
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Commonly seen along with renal failure in dogs. [[Uraemia]] irritates and damages the endocarium, particularly in the left atrium. Oedema is seen in the subendocardial tissue with deposition of glycosaminoglycans. This may progress to a necrotising endocarditis and, in extreme cases, left atrial rupture. If renal sufficiency is re-established then healing of the endocardial lesion is possible.
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[[Image:vegetative endocarditis.jpg|right|thumb|125px|<small><center>'''Vegetative endocarditis (dog)'''. Courtesy of T. Scase</center></small>]]
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==Species differences==
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'''Cattle''': the disease predominantly affects the tricuspid valve, perhaps due to bacteria arising in the GI tract and liver. Common underlying causes include liver abscesses, [[Traumatic Reticulitis|traumatic reticulitis]], metritis, mastitis, navel abscesses and 'joint ill'. Congestive right sided failure is manifested as ascites (including '''bottle jaw''') and embolisation to the lungs. [[:Category:Anaemia|Anaemia]] is often present as the red blood cells are damaged as they pass through the vegetation.
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===UlcerativeEndocarditis===
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'''Horse''': Lesions occur mainly on the mitral valve. The site of sepsis is often not identified but may be a sequale to septic jugular thrombophlembitis.  
Commonly seen along with renal failure in dogs.Uraemia irritates and damages the endocarium, particularly in the left atrium. Oedema is seen in the subendocardial tissue with deposition of glycosaminoglycans. This may progress to a necrotising endocarditis and, in extreme cases, left atrial rupture. If renal sufficieny is re-established then healing of the endocardial lesion is possible.
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==Species differences==
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'''Pig''' and '''Dog''': Lesions occur particularly on the mitral valve (71% of cases in dogs), perhaps due to the higher pressure blood flow on the left side of the heart leading to more valvular damage. Left sided heart failure and pulmonary oedema are seen clinically, as are emboli in various organs, particularly the kidney.
*Cattle: predominantly affects the tricuspid valve, perhaps due to bacteria arising in the GI tract and liver. Common underlying causes include Liver abcesses, traumatic reticulitis, metritis, mastitis, navel ancesses and 'joint ill'. Congestive right sided failure is manifested as ascites (including '''bottle jaw''') and embolisation to the lungs.  Anaemia is often present as the red blood cells are damaged as they pass through the vegetation.
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*Horse: Lesions occur mainly on the mitral valve. The site of sepsis is often not identified but may be a sequale to septic jugular thrombophlembitis.
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*Pig and dog: Lesions occur particularly on the mitral valve (71% of cases in dogs), perhaps due to the higher pressure blood flow on the left side of the heart leading to more valvular damage. Left sided heart failure and pulmonary oedema are seen clinically, as are emboli in various organs, particularly the kidney.
      
==Signalment==
 
==Signalment==
Endocarditis is rare in dogs but males and large breeds (e.g. german Shepherds) are most affected. Very rare in cats.
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Endocarditis is rare in dogs but males and large breeds (e.g. German Shepherds) are most affected. It is very rare in cats.
The disease mainly affects adult cattle and young pigs. In Horses, males are more comonly affected than females.   
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The disease mainly affects adult cattle and young pigs. In horses, males are more commonly affected than females.   
==Histroy & Clinical Signs==
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Clinical signs are often vague and rarely referable to congestive heart failure. The folowing clinical signs are seen related to sepsis:
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==History & Clinical Signs==
* Pyrexia
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Clinical signs are often vague and rarely referable to congestive heart failure. The following clinical signs are seen related to sepsis:
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*Pyrexia
 
*Lameness
 
*Lameness
 
*Neck Pain
 
*Neck Pain
*Lethargy/Anoexia
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*Lethargy/Anorexia
 
*Weight loss
 
*Weight loss
 
*Epistaxis
 
*Epistaxis
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Signs of embolisation to other organs may also be seen and those of congestive heart failure (dyspnoea, poor pulses, pale mucous membranes, tacchycardia, pulmonary crackles)
 
Signs of embolisation to other organs may also be seen and those of congestive heart failure (dyspnoea, poor pulses, pale mucous membranes, tacchycardia, pulmonary crackles)
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==Physical examination==
 
==Physical examination==
A variable murmur depending upon the valve affected. It may be noted that murmur has recently arisen or changed. Other clincial examination findings include joint effusions, lymphadenopathy, pyrexia and in advanced cases signs associated with disseminated intravascular coagulopathy (D.I.C) such as bleeding diathesis and petichiation.
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A variable murmur depending upon the valve affected. It may be noted that murmur has recently arisen or changed. Other clinical examination findings include joint effusions, lymphadenopathy, pyrexia and in advanced cases signs associated with [[Disseminated Intravascular Coagulation|disseminated intravascular coagulopathy]] (D.I.C) such as bleeding diathesis and petechiation.
    
==Diagnosis==
 
==Diagnosis==
 
===Laboratory findings===
 
===Laboratory findings===
 
'''Blood profiles''': Not all cases will have altered blood changes. Possible changes include:
 
'''Blood profiles''': Not all cases will have altered blood changes. Possible changes include:
::Haematology - Neutrophilia, left shift, monocytosis, Thrombocytopaenia and prolonged clotting times if developing D.I.C.
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::Haematology - [[Neutrophilia]], left shift, monocytosis, [[thrombocytopaenia]] and prolonged clotting times if developing D.I.C.
::Biochemistry - Hypoalbuminaemia and hypoglycaemia.
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::Biochemistry - [[Hypoalbuminaemia]] and hypoglycaemia.
'''Urinalysis''' : may have proteinuria, casts, pyuria. A uniary tract infection may be present with the same organism as is responsible for the endocarditis.  
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'''Urinalysis''' : may have proteinuria, casts, pyuria. A urinary tract infection may be present with the same organism as is responsible for the endocarditis.
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'''Blood cultures''' : Requires 3-4 sterile samples collected from the jugular vein at least 1 hour apart over a 24 hour period. Negative cultures do not rule out the possibility of bacterial endocarditis.  
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'''Blood cultures''' : Requires 3-4 sterile samples colected from the jugular vein at least 1 hour apart over a 24 hour period. Negative cultures do not rule out the possibility of bacerial endocarditis.
   
===Echocardiography===
 
===Echocardiography===
Structural abnormalities and vegetations may be visible on the valves although it is difficult to differentate from [[endocardiosis]].  
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Structural abnormalities and vegetations may be visible on the valves although it is difficult to differentiate from [[endocardiosis]].  
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===Radiography===
 
===Radiography===
 
Radiography is often unremarkable. There may be evidence of cardiomegaly or congestive heart failure if valvular damage is chronic or severe. Evidence of a focus of infection such as discospondylitis may be visible.
 
Radiography is often unremarkable. There may be evidence of cardiomegaly or congestive heart failure if valvular damage is chronic or severe. Evidence of a focus of infection such as discospondylitis may be visible.
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===Electrogcardiogram (ECG)===
 
===Electrogcardiogram (ECG)===
ECG may be normal. Arrhythmias detectected are often ventricular in origin (e.g. ventricular premature complexes) and represent extension of the inflammatory focus to invlove the myocardium. 3rd degree heart block may be present if the AV node is affected.
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ECG may be normal. Arrhythmias detectected are often ventricular in origin (e.g. ventricular premature complexes) and represent extension of the inflammatory focus to involve the myocardium. 3rd degree heart block may be present if the AV node is affected.
    
==Treatment==
 
==Treatment==
Antibiotic treatment with either a broad spectrum antibiotic or an appropriate antibiotic based on cultre and sensitivity results. Antibiotics should be administered intravenously for the first 5 days of therapy followed by a prolonged course (>4 weeks) of oral medication.  
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Antibiotic treatment with either a broad spectrum antibiotic or an appropriate antibiotic based on culture and sensitivity results. Antibiotics should be administered intravenously for the first 5 days of therapy followed by a prolonged course (>4 weeks) of oral medication.  
<br>Common Protocols use Ampicillin in combination with a Fluoroqunilone such as Enrofloxacin.
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<br>Common Protocols use [[Penicillins|Ampicillin]] in combination with a [[Fluoroquinolones|Fluoroquinolone]] such as Enrofloxacin.
 
<br>Secondary problems such as septic shock, D.I.C., congestive heart failure and embolisation need to be managed.
 
<br>Secondary problems such as septic shock, D.I.C., congestive heart failure and embolisation need to be managed.
    
==Prognosis==
 
==Prognosis==
Long term prognosis is guarded to poor. Possible complications include septic shock, Disseminated Intravascular coagulation, congestive heart failure and embolisation to other organs.
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Long term prognosis is guarded to poor. Possible complications include septic shock, disseminated intravascular coagulation, congestive heart failure and embolisation to other organs.
    
==References==
 
==References==
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[[Category:Endocardial_Pathology]][[Category:Cardiovascular_System_-_Inflammatory_Pathology]][[Category:Cattle]][[Category:Pig]][[Category:Sheep]]
 
[[Category:Endocardial_Pathology]][[Category:Cardiovascular_System_-_Inflammatory_Pathology]][[Category:Cattle]][[Category:Pig]][[Category:Sheep]]
[[Category:To_Do_-_Review]]
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[[Category:Expert_Review]]
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