Path 2 - Resp Quick 2

drraythe's version from 2016-04-11 03:11

Lungs Dzs/ Pneumonia

Question Answer
**What is Atelectasis? What are the 2 types?Meaning empty alveoli which do not contain air
Can be congenital or acquired
**What are 2 reasons for CONGENITAL (present at birth) Atelectasis?(1) Obstruction of airways due to meconium, aspirate, amniotic fluid
(2) Hyaline Membrane Dz (foals & piglets)
**What are 2 reasons for AQUIRED Atelectasis?(1) Compressive (pneumothorax, hydrothorax, bloat, neoplasm) (outside of lung)
(2) Obstructive (exudate, parasites, neoplasms, foreign material) (Inside of lung)
**What is the gross appearance of Atelectasis?The lung tissue in Atelectasis is dark red, flabby & depressed below the surface of surrounding lung
No air inside!
*What is the microscopic appearance of Atelectasis?Microscopically, the alveolar walls are congested & are in close opposition
*What is Emphysema? What are the 2 types?There is air trapped in the tissues
2 types are alveolar & interstitial
*Explain what is going on in Alveolar Emphysema? Gross appearance?Excessive air in the alveoli, czing abnormal & permanent enlargement of alveoli w/ destruction of alveolar walls
Emphysematous areas are raised, pale or white, dry & can be easily compressed w/ finger. It usually alternates areas of Atelectasis
*What is the cz of Alveolar Emphysema?It develops under the pressure of inhaled air → due to incompletely obstructed bronchioles
***Explain the difference in the bronchioles btwn Atelectasis & EmphysemaIn Atelectasis, there is NO AIR & the bronchioles are completely obstructed (FYI there are 3 types: Resorptive (complete blockage), Compressive (alveoli cannot open due to comression pressure from pleural cavity, ie: hydrothorax), Contractive (fibrotic changes, ie scarring))
In Emphysema, there IS AIR & bronchioles are incompletely obstructed (Alveoli are miss-shapen from dmg, but can still open & fxn a little)
***Explain Interstitial Emphysema. How does it appear grossly?Air collects in the connective tissue of lungs:
Interalveolar septa
Interlobular septa
Below the pleura around the bronchi & blood vessels
- Septa becomes thick, shiny, filled w/ bubbles
- Violent/traumatic type of Emphysema
*Who gets Interstitial Emphysema the most & why?Mostly seen in cattle, bc of developed interlobular septa & lack of collateral ventilation in adjacent lobules
*What are the 3 conditions which cz Interstitial Emphysema?Forced respiratory efforts, seen in following conditions:
(1) When death is followed by violent efforts in anoxia (Attempted CPR)
(2) During quick loss of blood in trauma, slaughter of fully conscious animal
(3) Death after protracted illness (air going in, animal is weak/sick, cant expel the air)
**What are the 2 types/czs of Pulmonary Edema?NON-INFLAMMATORY: Czd by factors that ↑ capillary hydraulic (formerly hydrostatic) pressure
INFLAMMATORY: Czd by factors that ↑ permeability of the air-blood barrier
*What are some factors that ↑ capillary hydraulic (formerly hydrostatic) pressure czing Non-Inflammatory Pulmonary Edema? (3)(1) ↑ left atrial pressure in left sided or bilateral cardiac failure (cardiogenic edema)
(2) Excessive fluid transfusion (Fluid therapy overload)
(3) Pulmonary venous occlusion
*What are some factors that ↑ permeability of the air-blood barrier czing Inflammatory Pulmonary Edema? (4)(1) Inhalation of corrosive gases - SO2, Cyanides, smoke (dmg to epithelial cells)
(2) Infectious agents (mycoplasma, viruses) (dmg to endothelial cells)
(3) Systemic toxins (dmg to endothelial cells)
(4) Anaphylaxis in certain species like the horse & cow (dmg to epithelial cells)
**Whats the prognosis of Pulmonary Edema?Poor/Grave, it is usually fatal
*Acute Respiratory Distress Syndrome (ARDS) → why does this happen? (3)Bc of diffuse alveolar dmg…. Due to:
(1) Systemic dzs
(2) Direct injury to lungs
(3) Lesions in other organ systems, like sepsis, multiple trauma, extensive burns & pancreatitis
***Explain the pathogenesis of ARDS (Acute Respiratory Distress Syndrome)Systemic dz/direct injury/lesions like sepsis, multiple traumas, extensive burns, pancreatitis → diffuse alveolar dmg & this triggers a large amt of macrophages to be released → they release a large amt of cytokinesCytokines prime neutrophils stationed in the lung capillaries to release enzymes & free radicals → Which czs diffuse endothelial/epithelial dmg → permeability edema → accumulation of inflammatory cells, formation of hyaline membrane & fibrosis, all of which results in Pulmonary edema
**Pulmonary hypertension → due to a what?An ↑ in pulmonary vascular resistance
Almost always 2⁰ to something else
**What are some cardiac dzs which lead to 2° pulmonary hypertension? (3)(1) Left sided heart failure
(2) Septal defects such as Mitral Insufficiency or Stenosis, Subaortic Stenosis, Cardiomyopathy
(3) Left to right shunt - Ventricular Septal Defect, Patent Ductus Arteriosus
**Sustained pulmonary hypertension results in??↑ pressure load to right ventricle w/ compensatory *right ventricular hypertrophy* & ultimately Rt CHF
**Infectious Bronchopneumonia occurs when...The risk factors tip the balance: Exposure, crowding, dehydration, other infxns & chronic dz.....**STRESS!!*
**What are the 2 main TYPES of CZS of Bronchopneumonia?(Aerogenous route)
(1) Bacteria & Mycoplasma
(2) Aspiration of feed & gastric contents
**Which dz has a CRANIO-VENTRAL distribution in the lungs?BRONCHOPNEUMONIA
**What are the 2 TYPES of Bronchopneumonia (& their alternative name)(1) Suppurative/lobular (suppurative is usually lobULAR) resolves in a week
(2) Fibrinous/LOBAR (fibrinous is usually lobAR)
*Bronchopneumonia is irregular consolidation of___region of lungCranioventral
**SUPPURATIVE Bronchopneumonia → where in the lungs is affected? What kinda exudate? What’s the pattern like? How would you describe the appearance of it?CRANIOVENTRAL part of lungs. Suppurative OR mucopurulent exudate. LobULAR in pattern, w/ a MOSAIC appearance (w/ red & grey color)
**Which type of Bronchopneumonia results from more severe injury bc of strong pathogens?FIBRINOUS bc it is LOBAR (affected entire lobes)
***What are 3 STRONG pathogens in CATTLE which can result in Fibrinous Bronchopneumonia?M. hemolytica (Pneumonic Pasteurellosis)
Mycoplasma mycoides subsp mycoides
Hemophillus somnus
**What are 2 STRONG pathogens in PIGS which can result in Fibrinous Bronchopneumonia?P. multocida
Actinobacillus pleuropneumoniae
**What are 2 STRONG pathogens in sheep/goats which can result in Fibrinous Bronchopneumonia?M. hemolytica
M. mycoides subsp mycoides (latter mainly in goats)
*INTERSTITIAL Pneumonia is confined to what structures?Alveolar walls & alveolar interstitium
(THE CT!!)
**What are the 2 routes of injury which can lead to INTERTITIAL Pneumonia?(1) Aerogenous injury to alveolar epithelium
(2) Hematogenous injury to alveolar capillaries
**Acute Interstitial Pneumonia usually begins w/ injury to what? This leads to what stage 1st? What is the stage following this?Starts w/ damage to either the Type I Pneumocyte (alveolar capillary endothelium) which results in exudation into the alveolar lumen, dubbed the EXUDATIVE Stage. The acute exudative stage is followed by the Proliferative stage where there is hyperplasia of Pneumocyte II
*What are the 5 major hallmarks of Chronic Interstitial Pneumonia?(1) Accumulation of mononuclear inflammatory cells in the interstitium & occasionally in the alveoli & bronchi
(2) Alveolar fibrosis
(3) Persistence of hyperplastic type II Pneumocyte
(4) Formation of microscopic granulomas
(5) Hyperplasia of smooth muscles in airways or pulmonary vasculature
***What are 5 important features of interstitial pneumonia?(1) Failure of lungs to collapse on opening of thoracic cavity
(2) Occasional presence of rib impressions on the lungs
(3) Lack of visible exudate in the lung & have meaty appearance
(4) Lungs are heavy & texture is elastic or rubbery
(5) Color varies from diffusely red to pale gray
***Abscesses in lung → describe what the abscesses look like when they are metastatic from septic emboli arrested in pulmonary vessels?Abscesses are small, multiple & widely distributed in whole lung, seen spreading from blood vessels. A careful search should be made to locate the source of emboli
**What are 4 main sources of septic emboli?(Result in embolic pneumonia)
(1) Rupture of hepatic abscesses (cattle)
(2) Infected jugular catheter
(3) Valvular endocarditis
(4) Other localized infxns
**What are the 3 main FUNGI CZS of Granulomatous Pneumonia?Coccidioides immitis
Blastomyces dermatidis
Histoplasma capsulatum
**What are the 2 main HIGHER BACTERIA CZS of Granulomatous Pneumonia?Mycobacterium spp.
Rhodococcus equui
**Which VIRUS can cz Granulomatous Pneumonia?FIP
*Enzootic Pneumonia of calves (Calf Pneumonia) is czd by?A VARIETY of etiological agents. Usually starts w/ a VIRAL infxn, but later bacterial contaminants like:
H. somnus
Actinomyces pyogenus
- produce a SUPPURATIVE Bronchopneumonia. (Lesions depend on stage of the dz!!)
*Enzootic Pneumonia of calves (calf pneumonia) is common at what age for what kind of cattle?1-4 month old dairy cattle
*Shipping Fever (transit fever, pneumonic Pasteurellosis) is a dz important in who, where?Important in feedlot cattle (usually calves/young cattle) in North America
**What is the etiological agent of Shipping Fever (aka transit fever aka Pneumonic Pasteurellosis)?Mannheimia hemolytica serotype 1 is believed to be etiological agent, which colonize the nasopharynx of normal! Calves. Agent, which colonize the nasopharynx of normal calves. ~Weaning, transport, crowding, starvation & viral infxns predispose for the condition
**When is Shipping Fever seen in calves?Dz is seen in calves 3 days to 3 weeks after exposure to unfavorable conditions of stress
***What are the CS & lesions of Shipping Fever?They are of Acute Fibrinous Bronchopneumonia!!!! (Severe congestion, hemorrhages & exudation of fibrin which accumulates on pleural surfaces, septa, alveoli & thoracic cavity. Remember its the more severe one, as compared to suppurative. Marbled appearance, Foci of coagulative necrosis encapsulated by connective tissue (sequestrum) are common)
**What are the lesions of respiratory Histophilosis?Fibrinous Bronchopneumonia (he didn't emphasize, but rest of lesions section said: Similar to pneumonic Pasteurellosis. A mixed infxn by H. somnus, M. hemolytica & mycoplasma is common)
*What is the etiological agent of Contagious Bovine Pleuropneumonia? Where does this dz geographically occur?Mycoplasma mycoides subspecies mycoides (small colony)
(Eradicated from North America!!!)
**What are the lesions of Contagious Bovine Pleuropneumonia?Fibrinous Bronchopneumonia, which is usually unilateral restricted to caudal lobes
*Mycoplasma bovis has what 2 manifestations???(1) As a component of Enzootic Pneumonia in young calves
(2) In Chronic Pneumonia & Polyarthritis in feedlot cattle
**What are the lesions M. bovis czs in the resp system?*Suppurative Bronchopneumonia.*! (He pointed out that all other mycoplasma cz Fibrinous Bronchopneumonia - except for this one)
*Hypersensitivity Pneumonitis (extrinsic allergic alveolitis) czs what kind of lesions?**Interstitial pneumonia**
*VIRAL pneumonia → Infectious Bovine Rhinotracheitis → (how is it usually xmitted?) WHERE are the lesions & WHAT are the lesions?(Usually aerosol) Gross lesions are usually restricted to nasal cavity, larynx & trachea. It is rare to have pulmonary lesions from this virus, however young calves may develop bronchointerstitial pneumonia!!
*VIRAL pneumonia → Bovine Respiratory Syncytial Virus (BRSV) → what is the kind of pneumonia this czs??Fatal Bronchointerstitial Pneumonia
*Haemophilus pneumonia → what is the ETIOLOGICAL agent?Haemophilus parasuis. Usually carried in the nasopharynx of normal pigs & following *******stress develops pneumonic lesions. (NOTE: (Cz of Glasser`s dz - Pericarditis, Pleuritis, Peritonitis, Polyarthritis & Meningitis in pigs)
*Haemophilus pneumonia → what are the LESIONS czd by this dz (& what's the agent again?)(Haemophilus parasuis) Czs ****Suppurative Bronchopneumonia
**Which porcine dz is a serious zoonosis czing meningitis, deafness & death in butchers & pig farmers?Streptococcal pneumonia (Streptococcus suis type II)
*What is the etiology of Chronic Enzootic Pneumonia? Which age does it affect?MULTIFACTORIAL!!
Affects YOUNGER SHEEP <1yr
**Caprine Arthritis Encephalitis presents in what 3 forms?(1) Non-Suppurative Encephalitis in young goats
(2) Arthritis & Synovitis in adult goats
(3) ******Chronic Interstitial Pneumonia**** & mastitis
*Rhodococcosis affects who, at what age & what is the etiological agent?HORSES specifically 2-4mo old foals, czd by Rhodococcus equi
NOTE: czs cervical lymphadenitis in cattle, goats, cats, dogs, pigs & immunocompromised humans
**Which horse dz can be zoonotic?Rhodosocciosis (Rhodococcus equi) can affect immunocompromised ppl
*Rhodococcosis (horses) czs what kinda pneumonia? What are other hallmark CS?*Bronchopneumonia (Pyogranulomatous Pneumonia) & acute death!
Also seen is weight loss, arthritis, diarrhea & subcutaneous abscess