Interstitial Pneumonia

interstitial pneumonia

_____________ Inflammation of the alveolar walls

alveolar septa, Type I pneumocytes, pulmonary capillaries

Damage and inflammatory response in interstitial pneumonia is centered on the _________, including _____________ and _________________.

restrictive disease

Interstitial pneumonia is considered a ________________________ due to the thickening and infiltration of the alveolar walls.

fluid, fibrin, inflammatory cells, reduced diffusion, hypoxia

Due to the restrictive nature of interstitial pneumonia:

Reduced compliance is due to the influx of ______, _________ and ___________.

Gas exchange is impaired due to __________ (increased wall thickness), and this results in __________

alveolar wall damage

Interstitial pneumonia is initiated by _____________________.

fibrin

Interstitial pneumonia timeline:

After the initial damage, __________ leaks into the alveolar space.

inflammatory cells, surfactant, hyaline membranes

Interstitial pneumonia timeline:

After fibrin enters the alveolar space, ____________ begin to infiltrate and fibrin reacts with _________ forming __________ over the old damage.

exudative phase

____________________: The phase of interstitial pneumonia where the alveolar septae are expanded and hyaline membranes are formed by fibrin and surfactant.

hyaline membranes

______________: glassy, protein-rich layers of dead cells and debris that line the alveoli (air sacs), blocking oxygen exchange and causing severe respiratory distress.

macrophages, type II pneumocytes, alveolar

Interstitial pneumonia timeline:

After hyaline membranes are formed, ___________ clean up the fibrin and debris, and ___________________ proliferate to cover the damage. But now the _______ is left thickened by inflammatory cells and edema.

true

true/false: interstitial pneumonia can either be resolved and the thickened walls differentiate and heal... or the lungs fail to collapse again and become swollen, and diffusely dark and rubbery

false, type I pneumocytes

true/false: Type II pneumocytes are extremely delicate and are a prime target cell for many viruses

cool

"When we think about septicemia, remember that the pulmonary capillary bed is the largest of such in the body. Septic bacterial pathogens are filtered through the lung, causing an inflammatory response centered on the capillaries in the septal wall."

Cool?

Type I epithelium, endothelium

•Histopathology of acute interstitial pneumonia centers on injury to _______________- or ___________________

exudative phase

Which interstitial pneumonia phase looks like this histologically?:

-Fluid and hyaline membranes fill the alveoli.

-Inflammatory cells, fibrin and edema thicken alveolar walls.

proliferative phase

Which interstitial pneumonia phase looks like this histologically?:

-Hyperplasia (mitosis) of type II pneumocytes.

-Fibrosis occurs with chronicity.

because it's usually not bacterial, EXCEPT SEPTICEMIA

Why is interstitial pneumonia typically diffuse?

aerogenous, hrmatogenous exposure

what is the typical route of exposure of interstitial pneumonia?

respiratory airway, alveolar epithelial cells, inflammatory, immune, alveolar wall

Viruses replicate in the _________ and ___________, causing damage and inducing a ______ and _________ response.

Inflammation is focused on the _________________

type I alveolar epithelium, fluid, protein, fibrin, hyaline membrane

Early response to viral damage to alveolar epithelium includes swelling and sloughing of _____________________ and the leakage of ________, ______ and ______ into the alveolar space, with the potential for _________ formation

fetalization

Chronic or persistent damage to alveolar walls leads to __________________ (persistent type II pneumocytes that don't differentiate to type I)

acute respiratory distress syndrome

_____________________: is a form of interstitial pneumonia with classic features like acute severe respiratory distress, pulmonary edema, and typically fatal outcome.

generalized systemic disease, injury to lungs, injury to other organs

What three categories of issues are conditions commonly associated with ARDS?

Viremia, Septicemia with endotoxemia, extensive burns and pancreatitis

What are some generalized systemic diseases typically associated with ARDS

aspiration of gastric contents, diffuse pulmonary infections

What are some things that cause injury to lungs and are associated with ARDS?

true

true/false: >50% of human ARDS are associated with mechanical trauma, sepsis, diffuse pulmonary infections and gastric aspiration.

sepsis, toxemia, pancreatitis

In veterinary medicine, see pulmonary edema very frequently in animals dying of ________, ___________ and ___________

cytokines, pulmonary capillaries, enzymes, free radicals

In ARDS, macrophages produce abundant ________ and activate neutrophils within __________ causing release of _______ and __________

alveolar, endothelial, edema, fibrin, hyaline membranes, fibroblasts, fibrosis

Ultimate outcome of ARDS intersitital pneumonia:

Diffuse _________ and __________ damage.

Abundant alveolar _________ and _________ exudation, with the formation of ______________.

____________ use the membranes as a scaffold for deposition of connective tissue leading to extensive ______________>

cool

Im choosing to ignore the histo description on slide 54 of the "lecture 8 and 9" ppt. You can look at it if you want... main thing, more type II pneumocytes than type I.

Cool?

diffuse, type I pneumocytes, type II pneumocytes, fibrin

the ultimate outcome of interstitial pneumonia:

_______ distribution.

damage to _________, persistence of __________ and deposition of ______ all impair gas exchange

Viruses act as primary pathogens with secondary bacterial infections

Bronchointerstitial pneumonia is the most common type of pneumonia seen in veterinary medicine.

Why?

aerogenous, virus with secondary bacterial infection

What is the route of bronchointerstitial pneumonia exposure?

What are the causes?

the causative agent, can avoid or persist better in tissues. Think fungus or foreign body. The immune system really struggles to clear this

Granulomatous pneumonia is an interstitial pneumonia with what important consideration?

Fungi, less often bacteria, virus or foreign material

What are the causes commonly of a granulomatous pneumonia?

Aerogenous or hematogenous

What is the route of exposure of a granulomatous pneumonia?

IV delayed type hypersensitivity

What type of hypersensitivity reaction is associated with a granulomatous pneumonia?

Multiple firm nodules, focal or multifocal

What are the gross lesions seen in a granulomatous pneumonia

Blastomyces dermatiditis., Mycobacterium sp. (Tuberculosis), Rhodococcus equi., Silicosis.

What are some common pathogens that cause granulomatous pneumonia?

airway, inhalation foreign material, bacteria, stomach acid

What is the route of exposure in aspiration pneumonia, and what causes it? (generally)

iatrogenic, dysfunctional pharync, meconium aspiration

What are three more specific reasons for aspiration pneumonia?

Cranioventral distribution, May be unilateral., Hemorrhage and atelectasis

What are the gross lesions associated with aspiration pneumonia?

Severe necrosis, Suppurative exudate., Aspirated material may be seen in airways.

What can be seen on histo with aspiration pneumonia?

hematogenous, bacterial emboli, lungs filter out septic emboli from the blood

What is the route of exposure of embolic pneumonia?

The cause?

And the pathogenesis? (How)

abscesses in ALL areas of the lung (all vs some tells this apart from bronchopneumonia)

What are the gross lesions associated with embolic pneumonia?