082-083-web

1Airways

82. Catarrhal, fibrinous (croupous) andaspiration (ichorous) pneumonia (in

general)

Structure of the lobule

Bronchiolus terminalis

Bronchuli respiratorii

Ductulialveolares

InfundibulumAlveolus

ACINUS

Structure of the alveolus

Basement membrane pneumocyte I.

respiratory cell pneumocyte II.

surfactant (anti-atelectaticfactor)

participant in regeneration pneumocyta III.

dog, rat cell of the

vegetative/autonomic nervous system

alveolar macrophage alveolar pores capillary network

Environment ofthe alveoli

United basement membrane inbetween to ease the gas exchange

Blood and air barrier

Pneumonias in animals Mostly caused by microorganisms

viruses, bacteria fungi, parasites other causes

allergy, inhalation of hot gases, aspiration Age special features

fetuses newborns sucking animals young animals adults

Pneumonias in fetuses Pathogens

Viruses: transplacental infection Bacteria, fungi: first inducing placentitis, infection of

the amniotic fluid, infection of the fetus and the lung calf

BHV-1 (bovine rhinotracheitis), PI-3-virus infection Brucella abortus, Listeria monocytogenes,

Chlamydophila psittaci, Actinomyces pyogenes, Mycoplasma sp., Ureaplasma sp. stb.

Aspergillus sp. foal

EHV-1 (equine rhinopneumonitis) dog

CHV-1 (canine herpesvirus infection) Mycoplasma canis, Chlamydophila psittaci

2Pneumonia in newborns(perinatal pneumonias)

neonatal pneumonia (collective category) Aerogenous infection before the newborn got the

colostrum (in state of hypogammaglobulinaemia) inhalation of different bacteria

calf, foal, goat Streptococcus sp. piglet Streptococcus sp., E. coli birds E. coli

Local process continues often to septicemia meconium aspiration syndrome

aspiration during parturition, typical or obturation, or pneumonia due to pathogens

Forms of pneumonias definition

inflammatory process in the parenchyma of the lung often accompanied with the lesions of the smaller or larger bronchi

Forms bronchoalveolar

serous, desquamative, catarrhal, suppurative, fibrinous (croupous)

interstitial granulomatous embolic-metastatic aspiration special

Bronchopneumonias:Inflammation hyperaemia, edema neutrophils, macrophages epithelial gaps, vascular permeability plasma fluid, proteins airspaceSerous bronchopneumonia

Desquamative bronchopneumonia

Desquamative bronchopneumonia Desquamative bronchopneumonia

3Serousbronchopneumonia

Normal shape, slightly enlarged, darker, gland-like by palpation, doesnt crepitate when cut, clear liquid oozes to the cut surface

Catarrhalbronchitis

Desquamative pneumonia

Bronchoalveolar pneumonia(bronchopneumonia)

Extension: lobules - lobularlobes - lobalfocal - pseudolobular

Fibrinous (croupous) pneumonia spreads quickly entire lobes are affected - Lobar pneumonia Development

Congestion, hemorrhage, massive exudation, fibrin accumulation Fibrin pleural surface = sero-fibrinous pleuritis

Appearance intense redness, firmer texture, consolidation, hepatization (red~, gray~). Dilation and thrombosis of lymph vessels edema thick septae marbled

appearance Focal coagulative necrosis. Sequestra. Histology

massive exudation fluid obliterates airspace. Neutrophils, macrophages. Fibroblasts

Stages initial phase

stadium incrementi s. hyperaemicum phase of hepatisation (std. hepatisationis)

red hepatisation (std. h. rubrae) grey hepatisation (std. h. griseae) yellow hepatisation (std. h. flavae)

phase of resolution (std. resolutionis) nasal discharge: mucoid or mucopurulent (P. m., B. b., Str.)

Croupous (fibrinous) pneumonia Croupous (fibrinous) pneumonia

4Croupous pneumonia Croupous pneumonia stadium incrementi

Croupous pneumonia - hepatisation Grey hepatisation

Croupous pneumonia hemorrhagic character Healing of the croupous pneumonia restitutio ad integrum

if the integrity of the tissue structure is maintained freed enzymes of the degenerated neutrophils cause fibrinolysis

partially absorbtion (lymph vessels) partially expectoration

epithel layer of the acini regenerates restitutio cum defectu

connective tissue proliferation from the wall of therespiratory ducts

carnificatio pulmonum

5Croupous pneumonia Due to direct (thrombotic) effect of the pathogen

Smaller or larger necrotic foci Sometime hemorrhagic character Secondary ichorous pneumonia on the affected areas

Cause of death: Suffocation or heart failure Following croupous pneumonia

Metastatic foci focal necrotizing-purulent-ichorouspneumonia

Allergic reaction in horses Hemorrhagic purpura, septic pododermatitis,

uveitis, urticaria

Croupous pneumonia

Pathology of the croupous pneumonia

shape maintained enlarged marbled liver-like (in stages of hepatisation) No crepitation on cutting! cut surface

mottled, homogenous dry, uneven, granular

Aspiration pneumonia

Different aspirated substances amniotic fluid milk, saliva, food, drinking water, blood fluid used for gastric lavage, contrast medium used for

filling the GI tract eructated or vomited gastric content

Consequences are different according to what type of material and what amount is aspirated where did the substance go if there where any putrefactive bacteria present

Aspiration pneumonia Aspiration pneumonia

6Aspiration pneumonia Aspiration pneumonia

Putrid bronchitis Putrefactive bacteria colonize in the mucous membrane

of the bronchi the mucous membrane necrotizes accompanied with putrid smell, the tissue debris

becomes soft fluid all the layers of the bronchi are affected

if there is enough time, the lungs also become affected usually the animal dies because of the absorbed

toxins

Ichorous pneumonia Way of infection:

Aerogenous infection (aspiration) putrid bronchitis first, than spreading to the lungs starts from the airways

lympho-haematogenous infection may occur disseminated foci from the blood vessels of the interstitium

Due to putrefactive bacteria coagulation necrosis secondary softening in the necrotized areas

putrid smell, histolytic tissue debris causing intoxication (sapraemia)

acute ichorous abscess, ichorous cavern (cavity) Slow, delayed demarcation

Ichorous pneumonia

83. Interstitial, suppurativeand embolic pneumonias

(in general)

Interstitial pneumonia Majority of the lesions

In the interstitium Most typical lesions:

acute, subacute, chronic proliferative inflammation besides proliferative processes immunpathological

processes, accumulation of immune cells Appearance:

intralobular (interalveolar) interlobular between the lobules peribronchial around the small bronchi

7Intralobular (interalveolar) interstitial pneumonia Mild proliferation of the alveolar interstitiumIntralobular (interalveolar) interstitial pneumonia

Severe proliferation of the alveolar interstitiumIntralobular (interalveolar) interstitial pneumonia

Immunpathologic processIntralobular (interalveolar) interstitial pneumonia

Peribronchial interstitial pneumonia Interstitial pneumonia

Proliferative processes in the alveoli Epithelisation

pneumocyta II. Pseudoepithelisation

alveolar macrophages Age of the process

acute histiocyte and macrophage proliferation subacute pronounced cell proliferation chronic severe fibrosis

8Pathogen has an effect inside the alveoliIntralobular (interalveolar) interstitial pneumonia Epithelisation

Pseudoepithelisation Chronic interstitial pneumonia

Suppurative pneumonia(pneumonia purulenta)

Typically embolic or metastatic If hematogenous:

Purulent process somewhere in the body distributed abscesses in the lung (no surrounding inflammation)

If bronchiogenous: First catarrhal or croupous pneumonia occurs and

secondary purulent foci are formed Pathogens:

cattle/pig Arcanobacterium (Actinomyces) pyogenes rabbit Staphylococcus aureus horse Streptococcus equi, Rhodococcus equi

Purulent bronchopneumonia

9Purulent bronchopneumonia

Pneumonia with granulome formation Accompaying other disease

Lympho-hematogenous metastasis Embolic-metastatic pneumonia Possible nodules

necrotic foci purulent (ichorous) abcesses ichorous foci

Appearance: solitaer focus (smaller - larger) evenly disseminated foci foci of the same age / or prolonged form

Necrotic pneumonia Sequestrum formation after necrotic pneumonia

Mass of necrotic lung parenchymaseprated from viable lung tissue bypurulent exudate and usuallyencased in a fibrous capsule

10

Embolic-metastatic pneumonia Chronic purulent abscess formation(cut surface)

Port of entry Purulent-ichorous pneumonia

Granulomatous pneumonia Granulomatous pneumonia

11

Granulomatous pneumonia Locus minoris resistanciae

Special pneumonias Actinobacillus pleuropneumonia

serous-hemorrhagic-proliferative-necrotizing in hours, death in 1-2 days pronounced macrophage proliferation extended demarcation

sero-fibrinous pleuritis perifocal edema

Anthrax Aerogenous infection (piglet inhales the spores) Serous, hemorrhagic, necrotizing pneumonia Spore reaches the deep areas of the lung, starts to

proliferate rapid course