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+ | |||
+ | {{toplink | ||
+ | |backcolour = D1EEEE | ||
+ | |linkpage =Cardiorespiratory System - Pathology | ||
+ | |linktext =Cardiorespiratory System | ||
+ | |maplink = Cardiorespiratory System (Content Map) - Pathology | ||
+ | |pagetype =Pathology | ||
+ | |sublink1=Respiratory System Inflammation - Pathology | ||
+ | |subtext1=RESPIRATORY SYSTEM INFLAMMATION | ||
+ | }} | ||
+ | <br> | ||
+ | ==In general== | ||
+ | |||
+ | *Main clinical expression is as secondary invaders of previously damaged lung tissue due to viral or parasitic involvement or environmental stress | ||
+ | *Some are initial pathogens in their own right while others can damage the tract allowing invasion by more pathogenic types | ||
+ | |||
+ | ==In Dogs== | ||
+ | |||
+ | ===Infectious canine tracheitis=== | ||
+ | |||
+ | *See [[Respiratory Viral Infections - Pathology#In Dogs|Infectious canine tracheitis]] | ||
+ | *Synonym: '''Kennel cough''' | ||
+ | *Multiple agents implicated | ||
+ | |||
+ | ===Tuberculosis in dogs=== | ||
+ | |||
+ | *Dogs are rarely susceptible to [[:Category:Mycobacterium species|''Mycobacterium'' spp.]] causing tuberculosis [[Respiratory Bacterial Infections - Pathology#Tuberculosis|in cattle]], usually either from human or farm animal source | ||
+ | *Gross pathology: | ||
+ | **Multifocal nodules, firm, calcified with necrotic centres | ||
+ | **Usually caudal lung lobes | ||
+ | **Also [[Pleural Cavity & Membranes Inflammatory - Pathology|granulomatous pleuritis]] and [[Pleural Cavity & Membranes Degenerative - Pathology#Haemothorax|haemothorax]] | ||
+ | |||
+ | ===Nocardiosis=== | ||
+ | |||
+ | *Caused by ''[[:Category:Nocardia|Nocardia]]'' | ||
+ | *Grossly: | ||
+ | **Haemorrhagic purulent exudate in [[Pleural Cavity & Membranes Inflammatory - Pathology|pleural cavity]] | ||
+ | **Yellow granules on pleural surface | ||
+ | *Possibly caused by penetrating awns of grass | ||
+ | *Mainly in sporting breeds | ||
+ | |||
+ | ==In Cats== | ||
+ | |||
+ | ===Feline Chlamydiosis=== | ||
+ | |||
+ | *Persistent respiratory infection caused by [[Chlamydophila psittaci|''Chlamydia psittaci (felis)'']] | ||
+ | *Mild conjunctivitis, serous purulent [[Nasal Cavity Inflammatory - Pathology#Infectious causes of rhinitis|rhinitis]] and conjunctivitis, in severe cases mild [[Lungs Inflammatory - Pathology#Bronchointerstitial pneumonia|bronchointerstitial pneumonia]] - feline pneumonitis | ||
+ | |||
+ | ===[[:Category:Mycoplasmas|''Mycoplasma felis'']]=== | ||
+ | |||
+ | *Can also cause mild respiratory infection | ||
+ | |||
+ | ==In Horses== | ||
+ | |||
+ | *[http://www.ivis.org/special_books/Lekeux/chanter/chapter_frm.asp?LA=1 Overview of equine respiratory disease] by N Chanter of the Animal Health Trust, taken from Equine respiratory diseases edited by P Lekeux. Chapters of this book are published by the International Veterinary Information Service (IVIS) | ||
+ | |||
+ | ===[[Strangles]]=== | ||
+ | |||
+ | |||
+ | |||
+ | ===''[[Streptococcus equi subsp. zooepidemicus]]''=== | ||
+ | |||
+ | |||
+ | ===Glanders=== | ||
+ | |||
+ | *Caused by [[Burkholderia mallei|''Burkholderia (Pseudomonas) mallei'']] | ||
+ | *Exists in eastern Europe and Asia | ||
+ | *Notifiable in UK | ||
+ | *Characterised by multiple small submucosal [[Nasal Cavity Inflammatory - Pathology#Infectious causes of rhinitis|nasal nodules]] which liquefy and ulcerate | ||
+ | **Cores of [[Neutrophils|neutrophils]] surrounded by a rim of macrophages and [[Chronic Inflammation - Pathology#Granulation tissue|granulation tissue]] | ||
+ | *In addition may have similar nodules in [[Lungs Inflammatory - Pathology#Infectious causes of pneumonia|lungs]], '''lymph nodes''' and '''cutaneous lymphatics''' | ||
+ | *Clinical signs: fever and head/ neck lymphadenitis, [[Nasal Cavity Inflammatory - Pathology#Infectious causes of rhinitis|rhinitis]] | ||
+ | |||
+ | ===''Rhodococcus equi''=== | ||
+ | [[Image:Pyogranulomatous lungs due to Rhodococcus Equi.jpg|right|thumb|100px|<small><center>Pyogranulomatous lesions due to Rhodococcus equi (Image sourced from Bristol Biomed Image Archive with permission)</center></small>]] | ||
+ | |||
+ | *Causative agent [[Rhodococcus equi|''Rhodococcus (Corynebacterium) equi'']] | ||
+ | *Important cause of sever, often fatal [[Lungs Inflammatory - Pathology#Granulomatous pneumonia|granulomatous]] [[Lungs Inflammatory - Pathology#Infectious causes of pneumonia|pneumonia]] in foals | ||
+ | *Clinical signs include depression, cough, weight loss, respiratory distress, diarrhoea, arthritis, subcutaneous abscesses | ||
+ | *Bacterium survives phagocytosis and multiplies | ||
+ | *Bacterial toxins -> caseous necrosis in lungs -> attracts inflammatory cells -> pyogranulomatous pneumonia | ||
+ | *Grossly: | ||
+ | **Multiple firm nodules, usually no encapsulation | ||
+ | **Partial [[Lungs Ventilation - Pathology#Atelectasis (Collapse)|atelectasis]] | ||
+ | *Histologically: | ||
+ | **Pyogranulomatous lesions | ||
+ | **Macrophages with ingested microorganisms in the alveoli | ||
+ | **Necrosis spreading through parenchyma | ||
+ | |||
+ | ==In Cattle== | ||
+ | |||
+ | ===Necrotic laryngitis=== | ||
+ | [[Image:Necrotising laryngitis.jpg|right|thumb|100px|<small><center>Necrotising laryngitis (Image sourced from Bristol Biomed Image Archive with permission)</center></small>]] | ||
+ | [[Image:Tracheitis in calf diphtheria.jpg|right|thumb|100px|<small><center>Tracheitis in calf diphtheria (Image sourced from Bristol Biomed Image Archive with permission)</center></small>]] | ||
+ | |||
+ | *Synonyms: '''laryngeal diphtheria, calf diphtheria''' | ||
+ | *Common disease in cattle, and can occur in swine | ||
+ | *Caused by infection with [[Fusobacterium|''Fusobacterium necrophorum'']] | ||
+ | *Lesions may also be found in other parts of the [[Nasopharynx Inflammatory - Pathology#Infectious causes of pharyngitis|oropharynx]] | ||
+ | *The bacterium usually gains entry through damaged mucosal surfaces e.g. after viral infections or injury following (poor!) use of dosing guns, coarse poor quality roughage | ||
+ | *Results in severe acute neutrophilic [[Larynx Inflammatory - Pathology#Infectious causes of laryngitis|laryngitis]] | ||
+ | *Extensive accumulation of fibrin and necrotic cellular debris on the ulcerated mucosal surface | ||
+ | *Lesions appear as dry plaques of fibrinonecrotic exudate and ulceration on the laryngeal mucosa | ||
+ | *Inhalation of exudate and bacterial organisms may cause [[Bronchi and Bronchioles Inflammatory - Pathology#Infectious causes of bronchitis or bronchiolitis|broncho]][[Lungs Inflammatory - Pathology#Infectious causes of pneumonia|pneumonia]] | ||
+ | *Death may result from toxaemia or asphyxiation | ||
+ | *Also may occur in pigs | ||
+ | |||
+ | ===''CAR bacillus''=== | ||
+ | |||
+ | *Causative agent: [[Bacillus species|''Cillia-associated respiratory bacillus'']] | ||
+ | *An unclassified bacteria that can't be grown in culture | ||
+ | *Colonises ciliated epithelium in '''rodents''' and ruminants | ||
+ | *Associated with [[Nasal Cavity Inflammatory - Pathology#Infectious causes of rhinitis|chronic lymphocytic rhinitis]], [[Trachea Inflammatory - Pathology#Infectious causes of tracheitis|tracheitis]] and [[Bronchi and Bronchioles Inflammatory - Pathology#Infectious causes of bronchitis or bronchiolitis|bronchitis]] | ||
+ | *Clinical disease in '''rabbits''' and '''rodents''' | ||
+ | *Subclinical disease in ruminants | ||
+ | |||
+ | ===Pneumonic pasteurellosis=== | ||
+ | |||
+ | *Synonym: '''Shipping fever''' | ||
+ | *Caused by [[Mannheimia haemolytica|''Manheimia haemolytica'' biotype A serotype 1 (90%)]] and ''[[Pasteurella multocida]]'' | ||
+ | *In young, growing cattle | ||
+ | *In clinically normal cattle ''Mann. haemolytica'' serotype 2 is present in low numbers, only in nasal cavity and tonsils | ||
+ | *Clinical signs: depression, anorexia, rapid shallow respiration, crusty nose with mucopurulent discharge, serous ocular discharge | ||
+ | *Acute [[Bronchi and Bronchioles Inflammatory - Pathology#Infectious causes of bronchitis or bronchiolitis|bronchopneumonia]] and may progress to [[Lungs Inflammatory - Pathology#Lobar pneumonia|lobar pneumonia]] with toxaemia | ||
+ | *Pathology | ||
+ | **Lobar, cranioventral exudative pneumonia with fibrin, [[Pleural Cavity & Membranes Inflammatory - Pathology|fibrinous pleuritis]], areas of coagulative necrosis | ||
+ | *Histology | ||
+ | **Large numbers of bacteria are usually associated with necrotic lesions | ||
+ | |||
+ | ===Tuberculosis=== | ||
+ | [[Image:Tuberculosis M bovis.jpg|right|thumb|100px|<small><center>Tuberculosis caused by ''M. bovis'' (Image sourced from Bristol Biomed Image Archive with permission)</center></small>]] | ||
+ | |||
+ | *Caused by ''[[Mycobacterium bovis]]'' and ''M. tuberculosis'' | ||
+ | *Reside primarily within macrophages where they multiply and result in characteristic [[Lungs Inflammatory - Pathology#Granulomatous pneumonia|granulomatous inflammation]] (macrophages and giant cells, epithelioid cells) | ||
+ | *Cattle can be infected by inhalation of the organism or through milk | ||
+ | *'''The primary complex''' | ||
+ | **Describes the initial focus of infection at the portal of entry (lungs) plus involvement of regional lymph nodes | ||
+ | **90% of cases exhibit the pulmonary form | ||
+ | **Grossly: | ||
+ | ***Small tubercles in dorsocaudal subpleural areas which progress to larger confluent areas of caseous necrosis | ||
+ | ***Usually start at bronchio-alveolar junction an progress to the alveoli | ||
+ | ***Caseous lesions, may calcify or be encapsulated | ||
+ | ***Multiple foci may coalesce | ||
+ | ***Ulcers in [[Trachea Inflammatory - Pathology|trachea]] and [[Bronchi and Bronchioles Inflammatory - Pathology#Infectious causes of bronchitis or bronchiolitis|bronchi]] due to coughed up bacteria | ||
+ | ***Spreads into [[Pleural Cavity & Membranes Inflammatory - Pathology|pleura]] | ||
+ | **Microscopically: | ||
+ | ***Typical granulomatous inflammation | ||
+ | ***Epitheliod and giant cells at centre of tubercles | ||
+ | ****Macrophages with ingested bacteria, forming epithelioid cells - large vesicular nuclei, abundant pale cytoplasm | ||
+ | ****Giant cells, formed by fusion of macrophages, with multiple nuclei | ||
+ | ***Narrow layer of lymphocytes, mononuclear cells and plasma cells at the periphery of the tubercle | ||
+ | ***With time, peripheral fibroplasia and central necrosis develop | ||
+ | *If the infection is not contained in the primary complex described above, the mycobacteria can disseminate via lymphatics to other organs and lymph nodes | ||
+ | *This can allow the development of '''miliary tuberculosis''', i.e. numerous small foci of infection in many organs/ tissues | ||
+ | |||
+ | ===Contagious bovine pleuropneumonia (CBPP)=== | ||
+ | [[Image:Contagious bovine pleuropneumonia.jpg|right|thumb|100px|<small><center>Contagious bovine pleuropneumonia (Image sourced from Bristol Biomed Image Archive with permission)</center></small>]] | ||
+ | |||
+ | *Caused by [[Mycoplasma mycoides subsp. mycoides|''Mycoplasma mycoides'']], small colony variant | ||
+ | *Causes a fibrinonecrotic [[Lungs Inflammatory - Pathology#Infectious causes of pneumonia|pneumonia]] and [[Pleural Cavity & Membranes Inflammatory - Pathology|fibrinous pleuritis]] | ||
+ | *Also affects caudodorsal areas | ||
+ | *[[Lungs Inflammatory - Pathology#Bronchopneumonia|Bronchopneumonia]] -> [[Lungs Inflammatory - Pathology#Lobar pneumonia|lobar pneumonia]] | ||
+ | *Sequestra are common | ||
+ | *NB: similarity to pneumonic pasteurellosis but CBPP has more pronounced marbled effect | ||
+ | *Interstitial septa are markedly widened by fibrinous exudate and the necrotic areas may have a fibrous capsule | ||
+ | *Large colony variant will cause a similar disease in goats | ||
+ | |||
+ | ===Enzootic pneumonia of calves=== | ||
+ | [[Image:Acute suppurative pneumonia.jpg|right|thumb|100px|<small><center>Acute suppurative pneumonia (Image sourced from Bristol Biomed Image Archive with permission)</center></small>]] | ||
+ | [[Image:Calf pneumonia.jpg|right|thumb|100px|<small><center>Calf pneumonia - chronic, with abscesses, fibrosis (Image sourced from Bristol Biomed Image Archive with permission)</center></small>]] | ||
+ | |||
+ | *Range of infectious agents together with managemental and environmental stress cause damage to the respiratory tract | ||
+ | *Causes unthriftiness in animals < 6 months old | ||
+ | *Usually the primary pathogen is a virus, secondary pathogens are bacteria and mycoplasmas | ||
+ | *Pathogens: | ||
+ | **[[:Category:Mycoplasmas|''Mycoplasmas'']] | ||
+ | ***Mycoplasmal [[Bronchi and Bronchioles Inflammatory - Pathology#Infectious causes of bronchitis or bronchiolitis|bronchitis]] and [[Lungs Inflammatory - Pathology#Infectious causes of pneumonia|pneumonia]] of calves is an important component of the syndrome of enzootic pneumonia | ||
+ | ***On its own causes Mycoplasmal ("Cuffing") pneumonia responsible for [[Bronchi and Bronchioles Inflammatory - Pathology#Infectious causes of bronchitis or bronchiolitis|bronchitis and bronchiolitis]] and [[Lungs Inflammatory - Pathology#Infectious causes of pneumonia|bronchointerstitial pneumonia]] | ||
+ | ***It is thought to pick up host antigens in order to prevent recognition by the body defences as foreign | ||
+ | ***In uncomplicated mycoplasma infection, the lesions are generally mild and consist of patchy red/purple areas of [[Lungs Ventilation - Pathology#Atelectasis|atelectasis]] in the '''cranio-ventral lung lobes''' | ||
+ | ***More confluent areas can develop with an underlying bronchointestitial pneumonia and resulting atelectasis | ||
+ | ***''M. bovis'' | ||
+ | ****Most pathogenic | ||
+ | ****Widespread lymphofollicular accumulations which contain germinal centres develop more slowly | ||
+ | ****These lesions can result in narrowing of the bronchiolar lumina - this is the classical lesion of '''‘cuffing pneumonia’''' | ||
+ | ***''M. dispar'' | ||
+ | ***''Ureaplasma'' sp. | ||
+ | **Viruses | ||
+ | ***[[Respiratory Viral Infections - Pathology#Respiratory syncytial virus|Bovine respiratory syncytial virus (BRSV)]] - can be primary, causes suppression of pulmonary immune response | ||
+ | ***[[Respiratory Viral Infections - Pathology#Parainfluenza- 3|Parainfluenza- 3 (PI3)]] - can be primary, causes suppression of pulmonary immune response | ||
+ | ***[[Flaviviridae|Bovine viral diarrhoea virus (BVDV)]] - suppression of pulmonary immune response | ||
+ | ***[[Adenoviridae|Adenoviruses]] | ||
+ | ***[[Coronaviridae|Calf coronavirus]] | ||
+ | ***[[Respiratory Viral Infections - Pathology#Infectious bovine rhinotracheitis (IBR)|Bovine herpes viruses]] | ||
+ | **Bacteria | ||
+ | ***[[Mannheimia haemolytica|''Manheimia (Pasteurella) haemolytica'' serotype A1]] | ||
+ | ***[[Pasteurella multocida|''Pasteurella multocida'']] | ||
+ | ***[[Arcanobacter pyogenes|''Arcanobacter pyogenes'']] | ||
+ | ***''[[Haemophilus somnus]]'' | ||
+ | *All transmitted by aerosol and direct contact | ||
+ | *Gross pathology: | ||
+ | **Consolidation of the cranioventral areas which increases in volume with duration | ||
+ | **On cut surface, exudate in the main airway of affected lobules with thickening of the surrounding connective tissue | ||
+ | *Micro pathology: | ||
+ | **Substantial lymphoid tissue around the airways | ||
+ | **Even to proper follicle formation, some of which may be large enough to compress the lumen | ||
+ | **Mixed cell exudate in the airway lumen | ||
+ | **Partial alveolar collapse distal to the compression | ||
+ | **Alveolar exudate contains a mixture of inflammatory cells | ||
+ | **Slight thickening of the alveolar walls with lymphocytes | ||
+ | |||
+ | ===Acute exudative pneumonia=== | ||
+ | |||
+ | *[[Lungs Inflammatory - Pathology#Infectious causes of pneumonia|Pneumonia]] in very young calves | ||
+ | *[[Arcanobacter pyogenes|''Arcanobacter pyogenes'']] is most frequently isolated | ||
+ | *Cranio-ventral distribution | ||
+ | |||
+ | ==In Sheep== | ||
+ | |||
+ | ===Laryngeal chondritis=== | ||
+ | [[Image:Oedema and chondritis in larynx of sheep.jpg|right|thumb|100px|<small><center>Oedema and chondritis in larynx of sheep (Image sourced from Bristol Biomed Image Archive with permission)</center></small>]] | ||
+ | |||
+ | *Caused by [[Fusobacterium|''Fusobacterium necrophorum'']] | ||
+ | *[[Larynx Inflammatory - Pathology#Infectious causes of laryngitis|Infection of laryngeal cartilages]] | ||
+ | *Can be seen in short-necked breed, e.g. Texels, East Friesians and Southdowns | ||
+ | *Leads to extreme respiratory distress | ||
+ | *Laryngeal mucosa is necrotic and ulcerated | ||
+ | *Associated with [[Larynx Degenerative - Pathology#Laryngeal oedema|laryngeal oedema]] | ||
+ | *Also may occur in young [[Hindgut Fermenters - Horse - Anatomy & Physiology|horses]] and calves | ||
+ | |||
+ | ===''CAR bacillus''=== | ||
+ | |||
+ | *As [[Respiratory Bacterial Infections - Pathology#CAR bacillus|in cattle]] | ||
+ | |||
+ | ===Enzootic pneumonia of lambs=== | ||
+ | |||
+ | *Caused by [[Mannheimia haemolytica|''Pasteurella (Manheimia) haemolytica'']], possibly together with [[:Category:Mycoplasmas|''Mycoplasma ovipneumoniae'']] | ||
+ | *Mainly in late spring/early summer after environmental stress i.e. handling or moving | ||
+ | *May be acute with producing a fibrinonecrotic [[Bronchi and Bronchioles Inflammatory - Pathology#Infectious causes of bronchitis or bronchiolitis|broncho]][[Lungs Inflammatory - Pathology#Infectious causes of pneumonia|pneumonia]] and associated [[Pleural Cavity & Membranes Inflammatory - Pathology|pleuritis]] | ||
+ | *Or tending towards chronicity with abscessation and fibrous pleural adhesions | ||
+ | *A septicaemic form (mortality 5%) is reported to follow the stress of movement to new pasture in the autumn in weaned lambs. | ||
+ | *Foci of necrosis containing many bacteria are seen at the site of initial invasion in the pharynx and in the '''[[Liver - Anatomy & Physiology|liver]]''' | ||
+ | *Meningitis in young lambs and mastitis in ewes are other expressions | ||
+ | |||
+ | ===Melioidosis (Pseudoglanders)=== | ||
+ | |||
+ | *Caused by [[:Category:Pseudomonas and Burkholderia species|''Pseudomonas (Malleomyces) pseudomallei'']], Closely related to [[Burkholderia mallei|''P. mallei'']] in [[Hindgut Fermenters - Horse - Anatomy & Physiology|horses]] | ||
+ | *Causes disease in sheep, goats and pigs, occasionally other species | ||
+ | *Starts as a pyemia and localises in varius tissues, including the lung as abscessation | ||
+ | **Encapsulated abscesses contain yellow, caseous or creamy pus | ||
+ | *[[Lungs Inflammatory - Pathology#Infectious causes of pneumonia|Pneumonia]] and arthritis are the most common presentation | ||
+ | |||
+ | ==In Pigs== | ||
+ | |||
+ | ===Atrophic Rhinitis=== | ||
+ | [[Image:Severe atrophic rhinitis.jpg|right|thumb|100px|<small><center>Severe atrophic rhinitis (Image sourced from Bristol Biomed Image Archive with permission)</center></small>]] | ||
+ | |||
+ | *Atrophy of nasal turbinates and distortion and shortening of the snout | ||
+ | *Caused by co-infection of the nasal mucosa with | ||
+ | **''[[Bordetella bronchiseptica]]'' | ||
+ | ***Appears to facilitate colonisation of nasal epithelium by the toxigenic ''Pasteurella'' | ||
+ | **Toxin-producing strain of [[Pasteurella multocida|''Pasteurella multocida'']] capsular type D (or sometimes A) | ||
+ | ***Experimental evidence shows that the toxin acts directly on bone cells of the nasal turbinates to cause bone loss, each pathogen can cause atrophy itself but greater damage when together | ||
+ | *Exacerbated by adverse dietary and managemental factors | ||
+ | *In rapidly growing young pigs (4-12 weeks old) | ||
+ | *Clinical signs | ||
+ | **Progressive facial deformity with [[Nasal Cavity Inflammatory - Pathology#Infectious causes of rhinitis|rhinitis]], catarrhal nasal discharge | ||
+ | **Sneezing, coughing, can progress to dyspnoea and anorexia | ||
+ | |||
+ | *Gross pathology | ||
+ | **Overlying skin on shortened snout is thrown into folds | ||
+ | **Deviation of the snout to most affected side | ||
+ | **Various loss of turbinate bone, ventral usually more affected | ||
+ | **Deviation of nasal septum away from affected chamber | ||
+ | **Inflammatory, haemorrhagic and ulcerative lesions in the nasal mucosa | ||
+ | *Micro pathology | ||
+ | **Reduction in the amount of bone in the turbinates | ||
+ | **No osteoid laid down between osteoblasts and existing bone | ||
+ | **Increased fibrous tissue | ||
+ | **Non-specific mucosal inflammation | ||
+ | |||
+ | *2 forms of the disease | ||
+ | **''''Progressive' atrophic rhinitis''' | ||
+ | ***Due to infection of the nasal turbinates by P.multocida strains carrying the toxA gene that encodes for an osteolytic toxin. [[Pasteurella multocida|''P.multocida'']] adheres poorly to mucous membranes, and therefore requires a predisposing nasal insult to assist colonisation eg: co-infection with [[Bordetella bronchiseptica|''B.bronchiseptica'']] or [[Cytomegalovirus|Porcine cytomegalovirus (inclusion body rhinitis)]] | ||
+ | ***Turbinate bone atrophy is permanent and progressive | ||
+ | **''''Non-progressive' atrophic rhinitis''' | ||
+ | ***Due to infection of the nasal turbinates by ''[[Bordetella bronchiseptica]]'' strains alone, that carry a gene that encodes for a dermonecrotic toxin. | ||
+ | ***Turbinate bone can regenerate by the time of slaughter | ||
+ | |||
+ | *''[[Bordetella bronchiseptica]]'' also causes [[Bronchi and Bronchioles Inflammatory - Pathology#Infectious causes of bronchitis or bronchiolitis|broncho]][[Lungs Inflammatory - Pathology#Infectious causes of pneumonia|pneumonia]] | ||
+ | |||
+ | ===Necrotic laryngitis in pigs=== | ||
+ | *As [[Respiratory Bacterial Infections - Pathology#In Cattle|in cattle]] | ||
+ | *Caused by infection with [[Fusobacterium|''Fusobacterium necrophorum'']] | ||
+ | |||
+ | ===Enzootic pneumonia of pigs=== | ||
+ | [[Image:Enzootic pneumonia of pigs.jpg|right|thumb|100px|<small><center>Enzootic pneumonia of pigs(Image sourced from Bristol Biomed Image Archive with permission)</center></small>]] | ||
+ | |||
+ | *Caused by ''[[Mycoplasma hyopneumoniae]]'' and ''[[Mycoplasma hyorhinis]]'' | ||
+ | *Also called '''mycoplasmal pneumonia''' | ||
+ | *Major cause of unthriftiness in young pigs | ||
+ | *[[Lungs Inflammatory - Pathology#Infectious causes of pneumonia|Pneumonia]] in weaned pigs | ||
+ | *Cough, reduced growth rate | ||
+ | *Attached to cilia - no [[Respiratory System General Introduction - Pathology#Mucociliary escalator|mucociliary clearance]] | ||
+ | *Usually non-fatal unless there is secondary infection (e.g. [[Pasteurella multocida|''Pasteurella multocida'']]) | ||
+ | *Gross pathology: | ||
+ | **Confluent consolidation of the cranioventral lung lobes | ||
+ | **In other areas there may be small red to grey focal lesions evident which indicate the bronchiolar orientation of the inflammatory process | ||
+ | *Histologically | ||
+ | **Changes result from a catarrhal [[Lungs Inflammatory - Pathology#Bronchointerstitial pneumonia|bronchointerstitial pneumonia]] | ||
+ | **In chronic cases, prominent accumulations of lymphoid cells can be seen around airways and blood vessels | ||
+ | |||
+ | ===''Actinobacillus pleuropneumoniae''=== | ||
+ | |||
+ | *Causative agent: ''[[Actinobacillus pleuropneumoniae]]'' | ||
+ | *Expolsive outbreaks of [[Lungs Inflammatory - Pathology#Infectious causes of pneumonia|pneumonia]] | ||
+ | *Spread by direct contact and aerosol | ||
+ | *Lesions | ||
+ | **Largely from toxin produced | ||
+ | **In diphragmatic lobes of the lungs | ||
+ | *Haemorrhage with [[Pleural Cavity & Membranes Inflammatory - Pathology|fibrinous pleuritis]] | ||
+ | *Usually localised, sometimes generalised | ||
+ | |||
+ | ===Pasteurellosis in pigs=== | ||
+ | |||
+ | *[[Pasteurella multocida|''Pasteurella multocida'']] can cause a severe acute fibrinous [[Bronchi and Bronchioles Inflammatory - Pathology#Infectious causes of bronchitis or bronchiolitis|broncho]][[Lungs Inflammatory - Pathology#Infectious causes of pneumonia|pneumonia]] in pigs | ||
+ | *The most significant disease here is that caused by ''P. multocida'' secondary to underlying [[:Category:Mycoplasmas|''mycoplasma'' pneumonia]], see above [[Respiratory Bacterial Infections - Pathology#Enzootic pneumonia of pigs|enzootic pneumonia of pigs]] | ||
+ | **This results in chronic suppurative [[Bronchi and Bronchioles Inflammatory - Pathology#Infectious causes of bronchitis or bronchiolitis|bronchopneumonia]] with abscessation and [[Pleural Cavity & Membranes Inflammatory - Pathology|pleuritis]] | ||
+ | *If there is considerable pleural involvement, it may be indistinguishable from lesions caused by ''[[Haemophilus pleuropneumonia]]'' (below) | ||
+ | *Also isolated from cases of meningitis and septicaemia in piglets | ||
+ | |||
+ | ===Contagious porcine pleuropneumonia=== | ||
+ | |||
+ | *Caused by [[Haemophilus pleuropneumonia|''Haemophilus (Actinobacillus) pleuropneumonia'']] | ||
+ | *Seen mainly between 6wks-6mths of age but will affect any age | ||
+ | *Highly pathogenic strains are capable of initiating disease on their own with high mortality in young pigs | ||
+ | *A fibrinonecrotic [[Bronchi and Bronchioles Inflammatory - Pathology#Infectious causes of bronchitis or bronchiolitis|broncho]][[Lungs Inflammatory - Pathology#Infectious causes of pneumonia|pneumonia]] with [[Pleural Cavity & Membranes Inflammatory - Pathology|pleurisy]] | ||
+ | *Foci of haemorrhagic consolidation or necrosis, mainly around major bronchi, tend to sequestrate | ||
+ | *Tending to spread throughout all lung lobes: therefore a cranioventral distribution may not be particularly evident | ||
+ | |||
+ | ===Glasser's disease=== | ||
+ | |||
+ | *Caused by ''[[Haemophilus parasuis]]'' | ||
+ | *May cause suppurative [[Bronchi and Bronchioles Inflammatory - Pathology#Infectious causes of bronchitis or bronchiolitis|broncho]][[Lungs Inflammatory - Pathology#Infectious causes of pneumonia|pneumonia]] and [[Pleural Cavity & Membranes Inflammatory - Pathology|pleuritis]] (as part of polyserositis) | ||
+ | *Stress of mixing, weaning and adverse environmental conditions are predisposing to the disease | ||
+ | |||
+ | ===Streptococcal pneumonia=== | ||
+ | |||
+ | *Caused by ''[[Streptococcus suis]]'' type II | ||
+ | |||
+ | ===Tuberculosis in pigs=== | ||
+ | |||
+ | *Pigs are susceptible to the [[:Category:Mycobacterium species|''Mycobacterium'' spp.]] causing tuberculosis [[Respiratory Bacterial Infections - Pathology#Tuberculosis|in cattle]] | ||
+ | *Rarely extends to lungs after haematogenous spread from ingested bacteria causing tubercles with various degrees of calcification, encapsulation and caseation | ||
+ | |||
+ | ==In Rabbits== | ||
+ | |||
+ | ===Snuffles=== | ||
+ | |||
+ | *Caused by [[Pasteurella multocida|''Pasteurella multocida'']], less commonly and/or ''[[Bordetella bronchiseptica]]'' | ||
+ | *Clinical signs (nasal discharge, sneezing) result from an acute to chronic [[Nasal Cavity Inflammatory - Pathology|rhinitis]] | ||
+ | |||
+ | ===''CAR bacillus''=== | ||
+ | |||
+ | *As [[Respiratory Bacterial Infections - Pathology#CAR bacillus|in cattle]] |
Revision as of 12:29, 12 June 2010
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In general
- Main clinical expression is as secondary invaders of previously damaged lung tissue due to viral or parasitic involvement or environmental stress
- Some are initial pathogens in their own right while others can damage the tract allowing invasion by more pathogenic types
In Dogs
Infectious canine tracheitis
- See Infectious canine tracheitis
- Synonym: Kennel cough
- Multiple agents implicated
Tuberculosis in dogs
- Dogs are rarely susceptible to Mycobacterium spp. causing tuberculosis in cattle, usually either from human or farm animal source
- Gross pathology:
- Multifocal nodules, firm, calcified with necrotic centres
- Usually caudal lung lobes
- Also granulomatous pleuritis and haemothorax
Nocardiosis
- Caused by Nocardia
- Grossly:
- Haemorrhagic purulent exudate in pleural cavity
- Yellow granules on pleural surface
- Possibly caused by penetrating awns of grass
- Mainly in sporting breeds
In Cats
Feline Chlamydiosis
- Persistent respiratory infection caused by Chlamydia psittaci (felis)
- Mild conjunctivitis, serous purulent rhinitis and conjunctivitis, in severe cases mild bronchointerstitial pneumonia - feline pneumonitis
Mycoplasma felis
- Can also cause mild respiratory infection
In Horses
- Overview of equine respiratory disease by N Chanter of the Animal Health Trust, taken from Equine respiratory diseases edited by P Lekeux. Chapters of this book are published by the International Veterinary Information Service (IVIS)
Strangles
Streptococcus equi subsp. zooepidemicus
Glanders
- Caused by Burkholderia (Pseudomonas) mallei
- Exists in eastern Europe and Asia
- Notifiable in UK
- Characterised by multiple small submucosal nasal nodules which liquefy and ulcerate
- Cores of neutrophils surrounded by a rim of macrophages and granulation tissue
- In addition may have similar nodules in lungs, lymph nodes and cutaneous lymphatics
- Clinical signs: fever and head/ neck lymphadenitis, rhinitis
Rhodococcus equi
- Causative agent Rhodococcus (Corynebacterium) equi
- Important cause of sever, often fatal granulomatous pneumonia in foals
- Clinical signs include depression, cough, weight loss, respiratory distress, diarrhoea, arthritis, subcutaneous abscesses
- Bacterium survives phagocytosis and multiplies
- Bacterial toxins -> caseous necrosis in lungs -> attracts inflammatory cells -> pyogranulomatous pneumonia
- Grossly:
- Multiple firm nodules, usually no encapsulation
- Partial atelectasis
- Histologically:
- Pyogranulomatous lesions
- Macrophages with ingested microorganisms in the alveoli
- Necrosis spreading through parenchyma
In Cattle
Necrotic laryngitis
- Synonyms: laryngeal diphtheria, calf diphtheria
- Common disease in cattle, and can occur in swine
- Caused by infection with Fusobacterium necrophorum
- Lesions may also be found in other parts of the oropharynx
- The bacterium usually gains entry through damaged mucosal surfaces e.g. after viral infections or injury following (poor!) use of dosing guns, coarse poor quality roughage
- Results in severe acute neutrophilic laryngitis
- Extensive accumulation of fibrin and necrotic cellular debris on the ulcerated mucosal surface
- Lesions appear as dry plaques of fibrinonecrotic exudate and ulceration on the laryngeal mucosa
- Inhalation of exudate and bacterial organisms may cause bronchopneumonia
- Death may result from toxaemia or asphyxiation
- Also may occur in pigs
CAR bacillus
- Causative agent: Cillia-associated respiratory bacillus
- An unclassified bacteria that can't be grown in culture
- Colonises ciliated epithelium in rodents and ruminants
- Associated with chronic lymphocytic rhinitis, tracheitis and bronchitis
- Clinical disease in rabbits and rodents
- Subclinical disease in ruminants
Pneumonic pasteurellosis
- Synonym: Shipping fever
- Caused by Manheimia haemolytica biotype A serotype 1 (90%) and Pasteurella multocida
- In young, growing cattle
- In clinically normal cattle Mann. haemolytica serotype 2 is present in low numbers, only in nasal cavity and tonsils
- Clinical signs: depression, anorexia, rapid shallow respiration, crusty nose with mucopurulent discharge, serous ocular discharge
- Acute bronchopneumonia and may progress to lobar pneumonia with toxaemia
- Pathology
- Lobar, cranioventral exudative pneumonia with fibrin, fibrinous pleuritis, areas of coagulative necrosis
- Histology
- Large numbers of bacteria are usually associated with necrotic lesions
Tuberculosis
- Caused by Mycobacterium bovis and M. tuberculosis
- Reside primarily within macrophages where they multiply and result in characteristic granulomatous inflammation (macrophages and giant cells, epithelioid cells)
- Cattle can be infected by inhalation of the organism or through milk
- The primary complex
- Describes the initial focus of infection at the portal of entry (lungs) plus involvement of regional lymph nodes
- 90% of cases exhibit the pulmonary form
- Grossly:
- Small tubercles in dorsocaudal subpleural areas which progress to larger confluent areas of caseous necrosis
- Usually start at bronchio-alveolar junction an progress to the alveoli
- Caseous lesions, may calcify or be encapsulated
- Multiple foci may coalesce
- Ulcers in trachea and bronchi due to coughed up bacteria
- Spreads into pleura
- Microscopically:
- Typical granulomatous inflammation
- Epitheliod and giant cells at centre of tubercles
- Macrophages with ingested bacteria, forming epithelioid cells - large vesicular nuclei, abundant pale cytoplasm
- Giant cells, formed by fusion of macrophages, with multiple nuclei
- Narrow layer of lymphocytes, mononuclear cells and plasma cells at the periphery of the tubercle
- With time, peripheral fibroplasia and central necrosis develop
- If the infection is not contained in the primary complex described above, the mycobacteria can disseminate via lymphatics to other organs and lymph nodes
- This can allow the development of miliary tuberculosis, i.e. numerous small foci of infection in many organs/ tissues
Contagious bovine pleuropneumonia (CBPP)
- Caused by Mycoplasma mycoides, small colony variant
- Causes a fibrinonecrotic pneumonia and fibrinous pleuritis
- Also affects caudodorsal areas
- Bronchopneumonia -> lobar pneumonia
- Sequestra are common
- NB: similarity to pneumonic pasteurellosis but CBPP has more pronounced marbled effect
- Interstitial septa are markedly widened by fibrinous exudate and the necrotic areas may have a fibrous capsule
- Large colony variant will cause a similar disease in goats
Enzootic pneumonia of calves
- Range of infectious agents together with managemental and environmental stress cause damage to the respiratory tract
- Causes unthriftiness in animals < 6 months old
- Usually the primary pathogen is a virus, secondary pathogens are bacteria and mycoplasmas
- Pathogens:
- Mycoplasmas
- Mycoplasmal bronchitis and pneumonia of calves is an important component of the syndrome of enzootic pneumonia
- On its own causes Mycoplasmal ("Cuffing") pneumonia responsible for bronchitis and bronchiolitis and bronchointerstitial pneumonia
- It is thought to pick up host antigens in order to prevent recognition by the body defences as foreign
- In uncomplicated mycoplasma infection, the lesions are generally mild and consist of patchy red/purple areas of atelectasis in the cranio-ventral lung lobes
- More confluent areas can develop with an underlying bronchointestitial pneumonia and resulting atelectasis
- M. bovis
- Most pathogenic
- Widespread lymphofollicular accumulations which contain germinal centres develop more slowly
- These lesions can result in narrowing of the bronchiolar lumina - this is the classical lesion of ‘cuffing pneumonia’
- M. dispar
- Ureaplasma sp.
- Viruses
- Bovine respiratory syncytial virus (BRSV) - can be primary, causes suppression of pulmonary immune response
- Parainfluenza- 3 (PI3) - can be primary, causes suppression of pulmonary immune response
- Bovine viral diarrhoea virus (BVDV) - suppression of pulmonary immune response
- Adenoviruses
- Calf coronavirus
- Bovine herpes viruses
- Bacteria
- Mycoplasmas
- All transmitted by aerosol and direct contact
- Gross pathology:
- Consolidation of the cranioventral areas which increases in volume with duration
- On cut surface, exudate in the main airway of affected lobules with thickening of the surrounding connective tissue
- Micro pathology:
- Substantial lymphoid tissue around the airways
- Even to proper follicle formation, some of which may be large enough to compress the lumen
- Mixed cell exudate in the airway lumen
- Partial alveolar collapse distal to the compression
- Alveolar exudate contains a mixture of inflammatory cells
- Slight thickening of the alveolar walls with lymphocytes
Acute exudative pneumonia
- Pneumonia in very young calves
- Arcanobacter pyogenes is most frequently isolated
- Cranio-ventral distribution
In Sheep
Laryngeal chondritis
- Caused by Fusobacterium necrophorum
- Infection of laryngeal cartilages
- Can be seen in short-necked breed, e.g. Texels, East Friesians and Southdowns
- Leads to extreme respiratory distress
- Laryngeal mucosa is necrotic and ulcerated
- Associated with laryngeal oedema
- Also may occur in young horses and calves
CAR bacillus
- As in cattle
Enzootic pneumonia of lambs
- Caused by Pasteurella (Manheimia) haemolytica, possibly together with Mycoplasma ovipneumoniae
- Mainly in late spring/early summer after environmental stress i.e. handling or moving
- May be acute with producing a fibrinonecrotic bronchopneumonia and associated pleuritis
- Or tending towards chronicity with abscessation and fibrous pleural adhesions
- A septicaemic form (mortality 5%) is reported to follow the stress of movement to new pasture in the autumn in weaned lambs.
- Foci of necrosis containing many bacteria are seen at the site of initial invasion in the pharynx and in the liver
- Meningitis in young lambs and mastitis in ewes are other expressions
Melioidosis (Pseudoglanders)
- Caused by Pseudomonas (Malleomyces) pseudomallei, Closely related to P. mallei in horses
- Causes disease in sheep, goats and pigs, occasionally other species
- Starts as a pyemia and localises in varius tissues, including the lung as abscessation
- Encapsulated abscesses contain yellow, caseous or creamy pus
- Pneumonia and arthritis are the most common presentation
In Pigs
Atrophic Rhinitis
- Atrophy of nasal turbinates and distortion and shortening of the snout
- Caused by co-infection of the nasal mucosa with
- Bordetella bronchiseptica
- Appears to facilitate colonisation of nasal epithelium by the toxigenic Pasteurella
- Toxin-producing strain of Pasteurella multocida capsular type D (or sometimes A)
- Experimental evidence shows that the toxin acts directly on bone cells of the nasal turbinates to cause bone loss, each pathogen can cause atrophy itself but greater damage when together
- Bordetella bronchiseptica
- Exacerbated by adverse dietary and managemental factors
- In rapidly growing young pigs (4-12 weeks old)
- Clinical signs
- Progressive facial deformity with rhinitis, catarrhal nasal discharge
- Sneezing, coughing, can progress to dyspnoea and anorexia
- Gross pathology
- Overlying skin on shortened snout is thrown into folds
- Deviation of the snout to most affected side
- Various loss of turbinate bone, ventral usually more affected
- Deviation of nasal septum away from affected chamber
- Inflammatory, haemorrhagic and ulcerative lesions in the nasal mucosa
- Micro pathology
- Reduction in the amount of bone in the turbinates
- No osteoid laid down between osteoblasts and existing bone
- Increased fibrous tissue
- Non-specific mucosal inflammation
- 2 forms of the disease
- 'Progressive' atrophic rhinitis
- Due to infection of the nasal turbinates by P.multocida strains carrying the toxA gene that encodes for an osteolytic toxin. P.multocida adheres poorly to mucous membranes, and therefore requires a predisposing nasal insult to assist colonisation eg: co-infection with B.bronchiseptica or Porcine cytomegalovirus (inclusion body rhinitis)
- Turbinate bone atrophy is permanent and progressive
- 'Non-progressive' atrophic rhinitis
- Due to infection of the nasal turbinates by Bordetella bronchiseptica strains alone, that carry a gene that encodes for a dermonecrotic toxin.
- Turbinate bone can regenerate by the time of slaughter
- 'Progressive' atrophic rhinitis
- Bordetella bronchiseptica also causes bronchopneumonia
Necrotic laryngitis in pigs
- As in cattle
- Caused by infection with Fusobacterium necrophorum
Enzootic pneumonia of pigs
- Caused by Mycoplasma hyopneumoniae and Mycoplasma hyorhinis
- Also called mycoplasmal pneumonia
- Major cause of unthriftiness in young pigs
- Pneumonia in weaned pigs
- Cough, reduced growth rate
- Attached to cilia - no mucociliary clearance
- Usually non-fatal unless there is secondary infection (e.g. Pasteurella multocida)
- Gross pathology:
- Confluent consolidation of the cranioventral lung lobes
- In other areas there may be small red to grey focal lesions evident which indicate the bronchiolar orientation of the inflammatory process
- Histologically
- Changes result from a catarrhal bronchointerstitial pneumonia
- In chronic cases, prominent accumulations of lymphoid cells can be seen around airways and blood vessels
Actinobacillus pleuropneumoniae
- Causative agent: Actinobacillus pleuropneumoniae
- Expolsive outbreaks of pneumonia
- Spread by direct contact and aerosol
- Lesions
- Largely from toxin produced
- In diphragmatic lobes of the lungs
- Haemorrhage with fibrinous pleuritis
- Usually localised, sometimes generalised
Pasteurellosis in pigs
- Pasteurella multocida can cause a severe acute fibrinous bronchopneumonia in pigs
- The most significant disease here is that caused by P. multocida secondary to underlying mycoplasma pneumonia, see above enzootic pneumonia of pigs
- This results in chronic suppurative bronchopneumonia with abscessation and pleuritis
- If there is considerable pleural involvement, it may be indistinguishable from lesions caused by Haemophilus pleuropneumonia (below)
- Also isolated from cases of meningitis and septicaemia in piglets
Contagious porcine pleuropneumonia
- Caused by Haemophilus (Actinobacillus) pleuropneumonia
- Seen mainly between 6wks-6mths of age but will affect any age
- Highly pathogenic strains are capable of initiating disease on their own with high mortality in young pigs
- A fibrinonecrotic bronchopneumonia with pleurisy
- Foci of haemorrhagic consolidation or necrosis, mainly around major bronchi, tend to sequestrate
- Tending to spread throughout all lung lobes: therefore a cranioventral distribution may not be particularly evident
Glasser's disease
- Caused by Haemophilus parasuis
- May cause suppurative bronchopneumonia and pleuritis (as part of polyserositis)
- Stress of mixing, weaning and adverse environmental conditions are predisposing to the disease
Streptococcal pneumonia
- Caused by Streptococcus suis type II
Tuberculosis in pigs
- Pigs are susceptible to the Mycobacterium spp. causing tuberculosis in cattle
- Rarely extends to lungs after haematogenous spread from ingested bacteria causing tubercles with various degrees of calcification, encapsulation and caseation
In Rabbits
Snuffles
- Caused by Pasteurella multocida, less commonly and/or Bordetella bronchiseptica
- Clinical signs (nasal discharge, sneezing) result from an acute to chronic rhinitis
CAR bacillus
- As in cattle