WikiVet English

Changes

Respiratory Parasitic Infections - Pathology (view source)

Revision as of 16:24, 31 July 2008

14,098 bytes added ,  16:24, 31 July 2008
no edit summary
Line 9: Line 9:  
}}
 
}}
 
<br>
 
<br>
 +
==In Dogs==
 +
 +
*Useful websites:
 +
**[http://www.ivis.org/advances/Parasit_Bowman/ddb_resp/chapter_frm.asp?LA=1 Cat and dog respiratory parasites (part 1)] - Nasal Mucosa and Sinuses, and Respiratory Parenchyma
 +
**[http://www.ivis.org/advances/Parasit_Bowman/ddb_resp2/chapter_frm.asp Cat and dog respiratory parasites (part 2)] - Trachea and Bronchi, and Pulmonary Vessels
 +
 +
===[[Metastrongyloidae|'''''Filaroides osleri''''']]===
 +
* = ''Oslerus osleri''
 +
*Colonise the [[Trachea - inflammatory#Infectious causes of tracheitis|trachea of dogs]]
 +
*Larva and adults accumulate in submucosal nodules of up to 1cm diameter at the tracheal bifurcation.
 +
*Minimal inflammatory host reaction to the nematodes when they are alive - the size of the nodule is related to the number and size of the nematodes within it.
 +
*When the parasites die, an intense foreign body reaction develops
 +
*Tracheal nodules can cause coughing, usually in young dogs <18 months old.
 +
*Severe infestation can cause significant occlusion of the airway.
 +
*Uncommon, but sometimes seen in coughing greyhounds
 +
 +
===[[Crustacea|''Linguatula serrata'']]===
 +
*Synonym: tongue worm
 +
*In [[Nasal cavity - inflammatory#Infectious causes of rhinitis|nasal passages]] of dogs, sometimes cats
 +
*May reach the [[Paranasal sinuses - inflammatory#Infectious causes of sinusitis|sinuses]]
 +
*Heavy infections may cause sneezing, coughing, nasal discharge
 +
 +
===[[Metastrongyloidae|''Angiostrongylus vasorum'']]===
 +
 +
*Adult worms live in the [[Lungs - circulatory|pulmonary arteries]] and '''right side of the heart''' dogs and foxes
 +
*Cause a proliferative endoarteritis
 +
*More severe damage is caused however by eggs lodging in arterioles and capillaries
 +
*In severe infection, this can result in [[Lungs - inflammatory#Infectious causes of pneumonia|pneumonia]] and [[Lungs - circulatory#Pulmonary oedema|pulmonary oedema]] as an acute syndrome
 +
*Circulatory impedance can result in congestive cardiac failure
 +
*Particularly a problem if dogs eats snails
 +
*Gross:
 +
**Patchy white appearance with haemorrhagic areas within
 +
*Microscopically:
 +
**Golden pigment within macrophages (haemosiderin)
 +
**Inflammation and scarring of alveolar walls -> enlargement of remaining air spaces
 +
*Worms secrete anticoagulant -> haemorrhage in other parts of body
 +
*May present as neurological cases due to the haemorrhage
 +
*May cause [[Lungs - circulatory#Embolism, thrombosis and infarction|pulmonary thromboembolism]]
 +
 +
===[[Filarioidea|''Dirofilaria immitis'']]===
 +
 +
*Establish in '''heart''' and [[Lungs - circulatory|pulmonary arteries]]
 +
*Larvae migrate through connective tissue
 +
*Immature adults move to caudal distal pulmonary arteries causing diffuse eosinophilic reaction in lung parenchyma, then migrate back to right ventricle
 +
*May cause [[Lungs - circulatory#Embolism, thrombosis and infarction|pulmonary thromboembolism]]
 +
 +
===[[Trichinelloidea|''Capillaria aerophila'']]===
 +
 +
*In [[Nasal cavity - inflammatory#Infectious causes of rhinitis|nasal passages]], [[Paranasal sinuses - inflammatory#Infectious causes of sinusitis|sinuses]], [[Trachea - inflammatory#Infectious causes of traacheitis|trachea]] and [[Bronchi and bronchioles - inflammatory#Infectious causes of bronchitis or bronchiolitis|bronchi]] of cats and dogs
 +
*Some dogs cough but often no symptoms
 +
*Mild catharral inflammation
 +
*In heavy infestation may cause obstruction of the lumen of airways and may develop into secondary [[Lungs - inflammatory#Bronchopneumonia|bronchopneumonia]]
 +
 +
===Toxoplasmosis===
 +
 +
*Caused by [[Tissue cyst-forming coccidia|''Toxoplasma gondii'']]
 +
*Cats are definitive hosts but other species may become intermediate hosts if they ingest the oocysts
 +
*Usually induces antibody response but remains silent clinically
 +
*Often show clinical signs when immunosuppressed
 +
*Involves many different tissues
 +
*Multifocal necrotising [[Lungs - inflammatory#Interstitial pneumonia|interstitial pneumonia]]
 +
*Proliferation of type II pneumocytes
 +
*Macrophage and neutrophil infiltration
 +
 +
===[[Metastrongyloidae|''Crenosoma vulpis'']]===
 +
 +
*Mainly parasite of foxes but dogs may become infected from snails and slugs
 +
*Adults in [[Bronchi and bronchioles - inflammatory#Infectious causes of bronchitis or bronchiolitis|small bronchi and bronchioles]]
 +
*Grossly:
 +
**Greyish lesions and consolidation in dorsal aspect of caudal lung lobes
 +
*Histologically:
 +
**Catharral, eosinophilic bronchitis ans bronchiolitis
 +
 +
==In Cats==
 +
 +
*Useful websites:
 +
**[http://www.ivis.org/advances/Parasit_Bowman/ddb_resp/chapter_frm.asp?LA=1 Cat and dog respiratory parasites (part 1)] - Nasal Mucosa and Sinuses, and Respiratory Parenchyma
 +
**[http://www.ivis.org/advances/Parasit_Bowman/ddb_resp2/chapter_frm.asp Cat and dog respiratory parasites (part 2)] - Trachea and Bronchi, and Pulmonary Vessels
 +
 +
===[[Crustacea|''Linguatula serrata'']]===
 +
*As in dogs above
 +
 +
===[[Metastrongyloidae|''Aelurostrongylus abstrussus'']]===
 +
 +
*Live in [[Lungs - inflammatory|lung parenchyma]] and [[Bronchi and bronchioles - inflammatory#Infectious causes of bronchitis or bronchiolitis|small bronchioles]]
 +
*Grossly:
 +
**Firm yellow nodules scattered throughout parenchyma, more frequently at periphery
 +
*Microscopically:
 +
**Eggs and larvae in the alveolar spaces cause a foreign body type reaction (surrounded by mononuclear cells and giant cells)
 +
**Submucosal gland hypertrophy and smooth muscle hypertrophy in airway and vessel walls
 +
*Associated clinical signs are mild although heavy infestations may -> chronic coughing
 +
*The airway eosinophilia which may be detected can be confused with a diagnosis of asthma
 +
 +
===[[Filarioidea|''Dirofilaria immitis'']]===
 +
*As in dogs above
 +
*Not very infective in cats but one dead adult causes acute pulmonary crisis - [[Lungs - circulatory#Embolism, thrombosis and infarction|thromboembolism]]
 +
 +
===[[Trichinelloidea|''Capillaria aerophila'']]===
 +
*As in dogs above
 +
 +
==In Horses==
 +
 +
===[[Ascaridoidea|''Parascaris equorum'']]===
 +
*Causes transient [[Nasal cavity - inflammatory#Infectious causes of rhinitis|nasal discharge]] when migrating through [[Lungs - inflammatory#Infectious causes of pneumonia|lungs]]
 +
**Foals and weanlings
 +
 +
===[[Trichostrongyloidea|''Dictyocaulus arnfieldi'']]===
 +
*Found in smaller [[Bronchi and bronchioles - inflammatory#Infectious causes of bronchitis or bronchiolitis|bronchi]]
 +
*Cause of chronic cough
 +
*Donkeys are a reservoir mostly without any clinical signs
 +
*Gross pathology:
 +
**Raised areas of over-inflated pulmonary tissue surrounding small bronchus, containing worms and mucopurulent exudate
 +
**Hyperplastic bronchial epithelium
 +
**Coiled worms in small bronchi
 +
**Peribronchial cuffing
 +
**In caudal lung lobes
 +
*Histologically
 +
**Central coiled parasites and associated chronic catharral bronchitis
 +
**Goblet cell hyperplasia
 +
**Lymphoid cell infiltration
 +
*In [[Hindgut Fermenters - Horse - Anatomy & Physiology|horses]], the worms usually fail to achieve sexual maturity
 +
 +
===[[Coccidia|''Besnoitia bennetti'']]===
 +
 +
*Papilloma like lesions in [[Larynx - inflammatory#Infectious causes of laryngitis|larynx]], skin and sclera
 +
*Thick walled parasitic cysts, covered by hyperplastic epithelium, may be ulcerated
 +
 +
==In Cattle==
 +
 +
===[[Trichostrongyloidea|''Dictyocaulus viviparus'']]===
 +
[[Image:Dictyocaulus viviparus.jpg|right|thumb|100px|<small><center>Dictyocaulus viviparus (Image sourced from Bristol Biomed Image Archive with permission)</center></small>]]
 +
[[Image:Parasitic bronchitis.jpg|right|thumb|100px|<small><center>Parasitic bronchitis (Image sourced from Bristol Biomed Image Archive with permission)</center></small>]]
 +
*Found in [[Trachea - inflammatory#Infectious causes of tracheitis|trachea]] and [[Bronchi and bronchioles - inflammatory#Infectious causes of bronchitis or bronchiolitis|large bronchi]]
 +
*Causes parasitic bronchitis, synonyms: bovine dictyocauliosis, husk, hoose
 +
*Primary infection:
 +
**Penetration phase (week 1)
 +
***Larvae migrate to lungs, no clinical signs
 +
**Prepatent phase (weeks 1-3)
 +
***Development and migration of larvae -> [[Bronchi and bronchioles - inflammatory#Bronchiolitis|bronchiolitis]] -> eosinophilic exudate -> air passage blocked -> alveolar collapse (distal to blockage) -> clinical signs (tachypnoea, coughing)
 +
**Patent phase (weeks 4-8)
 +
***Egg-producing mature worms
 +
***[[Bronchi and bronchioles - inflammatory#Bronchitis|Bronchitis]] - due to mature worms
 +
***[[Lungs - inflammatory#Verminous pneumonia|Parasitic pneumonia]] - due to aspiration of eggs and larvae -> cellular infiltration of neutrophils, macrophages, giant cells
 +
**Postpatent phase (weeks 8-12)
 +
***Majority of worms are expelled
 +
***In 25% of cases clinical signs may reappear as a result of alveolar epithelialisation
 +
***May be together with [[Lungs - ventilation#Emphysema|interstitial emphysema]] and [[Lungs - circulatory#Pulmonary oedema|pulmonary oedema]], or secondary bacterial infection
 +
*Reinfection syndrome:
 +
**Immune cattle show clinical signs only if exposed to large numbers
 +
**Pathogenesis - large numbers of larvae reach bronchioles where they are killed by immune response
 +
**Pathology - parasite granulomata (grey-green, 5mm diameter, macrophages, giant cells, eosinophils) and eosinophilic plugs in bronchioles
 +
<small>Above from RVC Parasitology study guide (2005-2006)</small>
 +
*Preferentially in dorsocaudaland ventrocaudal regions
 +
 +
*Histologically
 +
**Bronchial epithelium may show hyperplasia due to the chronic irritation
 +
**Cross-sections of the parasites
 +
**Exudate contains many eosinophils
 +
**Foci of necrosis in the rest of the lung tissue due to aspiration of eggs and larvae fromhese adults
 +
**In mild infestations, the adults are normally expelled in two months - self cure
 +
*Repeated infestation and secondary bacterial infection are common
 +
 +
*Two other types of lesion in lung tissue due to this worm have been reported:
 +
**Nodules (2-4mm in diameter) with greenish centres in the reinfection of an immune animal - the host mounting a successful defence and preventing larval migration
 +
**Pulmonary oedema and emphysema - thought to be a hypersensitivity response to a massive invasion of larvae in previously- sensitised animals - the gross and microscopic appearance is similar to that of [[Lungs - inflammatory#Acute bovine pulmonary emphysema and oedema (ABPEE)|fog fever]]
 +
 +
===Hydatid cysts===
 +
[[Image:Echinococcus cysts.jpg|right|thumb|100px|<small><center>Echinococcus cysts (Image sourced from Bristol Biomed Image Archive with permission)</center></small>]]
 +
 +
*The intermediate stage of [[Cestodes|''Echinococcus granulosus'']] can be found in the lungs of many species, most commonly in lungs of cattle and sheep
 +
*They range in size up to 5-10 cm diameter and although of little clinical significance, are important as a zoonosis (can be upto football size in man) and because of carcass condemnation
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
===[[Strongyloidea|''Syngamus laryngeus'']]===
 +
 +
*In [[Larynx - inflammatory#Infectious causes of laryngitis|larynx]] of cattle in Asia and South America
 +
 +
==In Sheep==
 +
 +
===Hydatid cysts===
 +
 +
As in cattle (above)
 +
 +
===[[Insecta|''Oestrus ovis'']]===
 +
*Larvae in the [[Nasal cavity - inflammatory#Infectious causes of rhinitis|nasal cavity]] of sheep and goats = Nasal bots
 +
*Causes reaction in [[Paranasal sinuses - inflammatory#Sinusitis|sinuses]]
 +
[[Media:Oestrus ovis.mp4]]
 +
 +
===[[Metastrongyloidae|''Protostrongylus'' spp.]]===
 +
*Adult worms block small [[Bronchi and bronchioles - inflammatory#Infectious causes of bronchitis or bronchiolitis|bronchioles]] resulting in accumulation of eggs, larvae and cellular debri distal to the blockage
 +
*Lesions resemble [[Parasitic infections#Dictyocaulus filaria|''Dictyocaulus filaria'']] but are fewer in numbers, lobular and at periphery of caudal lobes, they are very similar to [[Parasitic infections#Muellerius capillaris|''Muellerius capillaris'']] lesions
 +
 +
===[[Metastrongyloidae|''Muellerius capillaris'']]===
 +
 +
*Common in sheep and goats
 +
*Rarely any clinical significance
 +
*Grossly:
 +
**Multifocal [[Lungs - inflammatory#Interstitial pneumonia|interstitial]] [[Lungs - inflammatory#Infectious causes of pneumonia|pneumonia]] grossly evident as firm "lead-shot" nodules throughout the parenchyma, often with enveloping granulomatous response
 +
**Early stages are reddish in colour, turning later to greyish green, may calcify
 +
**Mostly in dorsal region of caudal lung lobes
 +
*Histologically:
 +
**Damaged alveolar septa with mild fibrous thickening and lymphocytic infiltrate
 +
**In more developed host resistance, foci of eosinophils around larvae, hyperplastic epithelium, macrophages, giant cells
 +
**May be some calcification
 +
 +
===[[Trichostrongyloidea|''Dictyocaulus filaria'']]===
 +
 +
*Most susceptible when first exposed to contaminated pasture
 +
*Animals < 1 year old
 +
*Pathogenesis and pathology similar to [[Parasitic infections#Dictyocaulus viviparus|''Dictyocaulus viviparus'']] in cattle
 +
*[[Bronchi and bronchioles - inflammatory#Infectious causes of bronchitis or bronchiolitis|Bronchitis]]
 +
 +
==In Pigs==
 +
 +
===[[Metastrongyloidae|''Metastrongylus'' spp.]]===
 +
 +
*Found in [[Bronchi and bronchioles - inflammatory#Infectious causes of bronchitis or bronchiolitis|bronchioles and smaller bronchi]]
 +
*Grossly:
 +
**Small grey nodules, especially along ventral border of caudal lobes
 +
**Adult worms in bronchi and bronchioles
 +
*Histologically:
 +
**Catarrhal and eosinophilic bronchitis and bronchiolitis
 +
**Possibly [[Lungs - ventilation#Atelectasis (Collapse)|atelectasis]]
 +
*Rarely becomes extensive
 +
*May transmit [[Respiratory Viral Infections - Pathology#Swine influenza|swine influenza]]
 +
 +
===[[Ascaris suum|''Ascaris suum'']]===
 +
 +
*May cause [[Lungs - inflammatory#Verminous pneumonia|parasitic pneumonia]] during a part of its migration
 +
*Larvae may be infected with [[Respiratory Viral Infections - Pathology#Swine influenza|Swine influenza]]
 +
*May cause severe pneumonia in calves housed where infected pigs were housed previously
 +
*Cause diffuse [[Lungs - inflammatory#Interstitial pneumonia|interstitial pneumonia]] with haemorrhage, [[Lungs - ventilation#Atelectasis (Collapse)|atelectasis]], [[Lungs - circulatory#Pulmonary oedema|interlobular oedema]] and [[Lungs - ventilation#Emphysema|emphysema]]
Retrieved from "https://en.wikivet.net/Special:MobileDiff/25086"