Path of Acute Pulmonary Infections Flashcards
What is Laryngeotracheitis?
It is a heterogenous group of illnesses that affect the larynx, trachea, bronchi, bronchioles, and lung parenchyma.
What is the etiology of laryngeotrachietis?
MC caused by viral (parainfluenza)
What is the pathogenesis of Laryngotrachietis?
There is viral infection –> interstitial inflammation of the upper airway with edema formation and infiltration of inflammatory cell –> smooth muscle thickening to produce wet cough–> narrowing of vocal cords + subglottic airway (inspiratory strifdor-larynx obstruction) and increased work of breathing
can lead to ARDS with hyaline membranes
atelectasis
What are the clinical features of laryngeotracheitis?
The clinical features of laryngeotrachietis is that is affects children, gradual onset (barking cough, inspiratory stridor–> worse at night
For croup, what happens in moderate to severe cases?
In moderate to severe cases, there is subcostal and intercostal retractions –> respiratory hypoxia/death
What is acute bronchitis?
Self limiting inflammation of the bronchi due to URI
What is the etiology of acute bronchitis?
It is parainfluenza, influenza A and B
What is the pathogenesis of Acute Bronchitis?
It is caused by bronchial inflammation –> ciliary inhibition and mucous production. Necrotic Epithelium sheds into pus, dead PMNs slough into mucus, and yellow green sputum is coughed up.
What is the morphology found in acute bronchitis?
Macroscopically: there is mucosal airway that is inflamed and congested.
Microscopically: There is small lobular bronchi/bronchioles filled with purulent exudate ( protein rich fluid and many neutrophils)
What are the clinical features of the Acute Bronchitis?
It is basically when there is cough lasting for more than 5 days ( 1-3 weeks) asscoiated with sputum production.
The treatment is supportive care.
What is the definition of pneumonia?
The definition of pneumonia is when there is inflammation of the lung parenchyma and is classified by etiological agent to determine tx.
What are the different types of pneumonia?
Community acquired pneumonia Health care associated Hospital Acquired Aspiration Necrotizing pneumonia and lung abscess Immunocompromised host pneumonia Chronic pneumonia
Community Acquired (CAP) is what?
Outside hospital in otherwise healthy with no health care association.
MCC bacterial strep pneumo. Atypical pneumonia ( mycoplasma pneumoniae), viral (COVID-19) legionella
Health Care-Associated
Nursing facility or outpatient hospital visit in last 30 days
MCC staph aureus (usually MRSA)
Hospital Acquired
HAP–> life threatening
Hospital stay usually first 48 hours. MCC staph aureus + strep pneumo+ pseudomonas (gram negative)
Aspiration
anaerobic flora
Necrotizing pneumonia and lung abcess
Staph aureus
Immunocompromised host pneumonia
CMV, Pneumocystis jiroveci
Chronic pneumonia
Mycobacterium tuberculosis
What are the clinical features of the pneumonia?
Fever, Sputum could indicate type of infection, and we cough, and depends on bug
What are the patterns of bacterial pneumonia?
Patchy consolidation.
Multilobar or bilateral.
Macroscopic: well developed lesions, elevated, dry grey-yellow, poor margins, centered around bronchiole
Microscopic: Neutrophil rich exudate fills bronchi/bronchiole and adjacent space
What is lobar pneumonia?
consolidation of lobe. Containes to one lobe.
Macro/micro findings depends on stage of the inflammatory response (high yield) -next slide
Look at the chart and memorize for the patterns of bacterial pneumonia (lobar)
look at chart
What is interstitial pneumonia?
Pathogenesis is alveolar type 1 cell damage –> edema–> hyaline membrane formation + ACE receptor stimulation –> causes hyperplasia of Type 2 cells + interstitial inflammation/capillary dilation/ recruitment of monocytes –> interstitial edema –> usually resolves spontaneously w/ supportive care or can cause fibrosis /ARDS/death
What is Mycoplasma Pneumonia and whom is it found in mostly?
It is walking pneumonia and is mainly found in children
What is the morphology of Mycoplasma Pneumonia?
What is the microscopic findings in mycoplasma pneuomoniae?
Congested, patchy, no pleuritis.
It is bronchiolitis, interstitial and some intra-alveolar involvement.
What is a lung Abcess?
Local suppurative/pus process that produces necrosis of lung tissue
What is the etiology of Lung abcess
Aerobic bacteria (S.Aureus and Strep) and anaerobes from oral cavity.
What is the common cause of lung abcess?
It can be caused by aspiration of infected material (RLL upright, RUL/ML if recumbant
Post pneumonic: after lung infection –> multiple, basal and diffusely scattered
Primary cryptogenic
Neoplasia (post-obstructive pneumonia)
Septic Emboli (multiple and diffusely scattered)
What is the pathogenesis of lung abcess
infection –> pneumonia–> damage–> necrosis
What is the morphology of pneumonia?
Microscopic is suppurative destruction of the lung tissue within a central area of cavitation –> gangrene –> fibroblastic proliferation –> fibrous wall
What are the clinical features of lung abcess?
Copious amounts of foul smelling sputum
What are the three types of chronic fungal pneumonias?
They are basically histoplasma capsulatum, coccidioides immitis, and blastomyces dermatitidis
What are the clinical features of chronic fungal/systemic mycosis?
It is basically a true pathogen–> infects healthy people, but more common in immunocompromised
