March 17 - Pulmonary Flashcards
Four stages of lobar pneumonia: timing, macro and micro findings
- Congestion: Seen in first 24 hours. Macro: red, heavy, boggy lobe. Micro: vasodilation, exudate full of bacteria
- Red hepatization: Seen in days 2-3. Macro: red and firm. Micro: exudate with red cells, PMNs, fibrin.
- Gray hepatization: Seen in days 4-6. Macro: grey-brown firm lobe. Micro: disintegrated RBCs, exudate with PMNs and fibrin.
- Resolution: Enzymatic digestion of exuate. Return to normal
Three pneumonia types
Bronchopulmonary: patchy inflammation of multiple lobules
Interstitial: inflammatoyr infiltrate of aveolar walls
Lobar: involves entire lobe of lung
Three ways to diagnose CF
- Increased sweat chloride (can be normal in mild disease.)
- Nasal potential difference measurements (more negative than normal)
- Genetic testing for CFTR mutations
Pathophysiology of CF in respiratory and gastric glands
Normal: CFTR increases Na+ and water content by secreting Cl-. Na+ stays extracellular for charge balance rather than being reabsorbed by ENAC channels.
CF: CFTR is impaired. Cl- can’t be secreted so Na+ reabsortpin is increased through the ENAC channels. Water follows resulting in viscous mucus.
Pathophysiology of CF in sweat glands
Normal: CFTR reabsorbs Cl-. Na+ follows through ENAC channels. Low salt content in sweat
CF: CFTR can’t reabsorb Cl- so high Cl- in sweat. Na+ follows for charge balance resulting in salty sweat
Nystatin
Polyene that inhibits ergosterol similar to amphotericin B. Given as swish and swallow agent for thrush (not absorbed in stomach)
Histoplasma vs coccidioides vs cryptococcus in clinical specimens
Histoplasma: Oval or round yeasts within macrophages
Coccidioides: large thick walled spherules containing endospores
Cryptococcus: Extracellular encapsulated yeast
Clearance of respiratory contaminants
Airways through the terminal bronchioles: mucociliary system
Distal to terminal bronchioles: alveolar macrophages
Airway anatomy: cartilate, goblet cells, epithelium types, smooth muscle, gas exchange
Cartilage: Present in trachea and bronchi
Goblet cells: Present in trachea and bronchi
Pseudostratified ciliated columnar epithelium: Trachea through terminal bronchioles
Cuboidal epithelium: Respiratory bronchioles
Simple squamous epithelium: Aveoli
Smooth muscle: Present through terminal bronchioles (in the conducting airways)
Gas exchange: respiratory bronchioles and aveoli; through the terminal bronchioles is conducting zone
Basis of ESR
Fibrinogen, an acute phase reactant, causes erythrocytes to form stacks that sediment faster. TNF-alpha, IL-1, and IL-6 stimulate production of acute phase reactants by liver, stimulating the systemic inflammatory response.
Airway resistence
Highest in medium sized bronchi, then drops dramatically as airways branch more
Elastin structure
Mostly nonpolar amino acids with proline and lysine like collagen but unlike collagen, not hydroxylated. Lysine deaminated, allowsing for desmoline cross links to form which gives elastin its rubber like properties
Aspiraiton pneumonia: locations
Supine: posterior segment of RUL, superior segment of RLL
Upright: basilar segments of lower lobes
Chediak-higashi presentation
Oculocutaneous albinism
Pyogenic infections
Neurologic dysfunction
Wiskott Aldrich syndrome: presentaiton and cause
Presentation: recurrent infections that worsen with age, easy bleeding, eczema
Cause: abnormal cytoskeleton, B and T cell dysfunction
Polyribosyl-ribitol-phosphate (PRP)
component of H flu capsule, immunogenic
Nocardiasis: cause, presentation, transmission
Cause: infection with Nocardia - branching gram pos rod that is partially acid fast
Transmission: spore inhalation or skin inoculation. Bacteria present in soil
Presentation: Pneumonia, brain abscess in elderly/immunocompromised
Listeria vs nocardia
Both gram pos rods. Listeria has tumbling motility; nocardai has branching filaments.
Listeria causes meningoencephalitis but not pulmonary disease. Nocardia causes pulmonary disease and brain abscess
Hamartoma: imaging and path
Most common benign lung tumor. Contains mature hyaline cartilage, fat, smooth muscle lined by respiratory epihtlieum. Coin shaped lesion on imaging.
Distinguishing between alpha hemolytic strep
Strep pneumo: optochin sens, bile soluble
Viridans strep: optochin resistance, bile insoluble
Bacteria asociated with hyponatremia
Legionella
Fungus associated with cave exploration
histoplasma
Langerhans giant cells
Multiple nuclei in horseshoe chape. Nonspecific finding in granulomatous inflammation. Form of activated macrophages
DHR flow cytometry
Alternative method to diagnose CGD. In CGD see absence of green fluorescence.