pulmonology Flashcards
def negative predictive value? how do you calculate it? relation to dz prevalence
- probability that pt truly does not have disease given a negative result
- d/ [(c+d)] (true negatives/total negative tests)
- varies inversely based on disease prevalvence
calculate specificity and sensitivity
spec-d/(b+d) (true negatives/total disease negatives)
sens- a/(a+c) (true positives/total disease positives)
codon vs frameshift mutation
codon has to be multiples of 3
frameshift can insertion or deletion of bases that are not multiples of three
frameshift vs point mutations
frameshift is insertion or deletion that results in new reading frame
point mutations aka base substitutions do not affect the reading frame
pt with killed viral vaccine will cause? not destruction by T-lymphoncytes because
hummoral response (i.e. impaired entry of influenza entry into cells by targeting HA). not cell-mediated b/c it’s a killed vaccine instead of attentuated
cell type found in respiratory tract, nose, paranasal sinuses, nasopharynx, most of larynx and trachobronchial tree? cell type found in oropharynx, laryngopharynx, anterior epiglottis, upper half of posterior epiglottis and vocal folds (true vocal cords)
- pseudostratified columnar, mucus secreting epithelium
- stratified squamous epithelium
mediators of granuloma formation/cellular response
vs
mediators of humoral responses
- IL-2, ad IFN-gamma which stimulate Th1 type CD4+ helper cells, and macrophage activation respectively
- mediated by Th2 type CD4+ helpers cells- produce IL-4 to activate IgE antibody production by B-cells, and Il-5 which promotes eosinophil activation and iGA synthesis from b-cells
pts neutrophils fail to turn blue upon nitroblue tetrazolium test indicates what type of infection?inheritance? role of the enzyme missing? which bacteria are resistant?
chronic granulomatous disease (CGD)- results from a deficiency in NADPH oxidase (produces reactive oxygen species “oxidative burst” that reduce nitroble tetrazolium to make blue pigment). X-linked. bacteria that have catalase are resistant neutrophils
alpha 1-antitrypsin deficiency definition. pulmonary and liver complications
alpha1-AT is a serum elastase inhibitor, without it elastin is disproportionately degraded.
associated with emphysema and liver cirrhosis.
tell pts to avoid smoking
mech of N-acetylcysteine in CF patients
cleaves disulfide bonds within mucus glycoproteins- loosening thick sputum
which antifungal drug acts on cell wall vs cell membrane?
echinocandins (caspofungin and micafungin), inhibits synthesis of polysaccharide glucan (essential component of fungal CELL WALL) vs membrane with other anti-fungals
-amp B and nystain bind ergosterol and form pores in cell membrane
is there a HIV vaccine? what is used as maternal prophylaxis during pregnancy? mech of action?
NO! nucleoside analog zidovudine (ZDV,AZT), a retroviral reverse transcriptase inhibitor.
in pts with COPD at what RR is work of breathing minimized? in increased elastic resistance?
work of breathing is minimized in pts with increased elastic resistance when RR is high and tidal volume is low (fast, shallow breaths)
vs pts with diseases that increase air flow resistance (COPD, asthma) work of breathing is minimized when rate is low and tidal volume is higher (slow deep breaths)
minute ventilation=
what happens if one of the two variables change?
tidal volume*RR.
if tidal volume changes body with change RR to maintain constant minute vent and save energy
i.e COPD increases TV or RR decreases
Restrictive pulomonary disease decreases TV and increases RR
hypoventilation has what A-a gradient?
normal
binding of O2 in lungs does what to H+ levels and CO2 levels? what is this called?
increases RBC release of H+ and CO2
-Haldane Effect
HHb-H+ + Hb (Hb is free to attach to O2)
H+ + HCO3-=H2CO3=H2O +CO2 (via carbonic anhydrase)
high concentrations of CO2 and H+ does what to O2 on Hb? what is this called?
causes release of O2- Bohr effect
H+ Hb (hemoglobin is released from O2)-HHb
CO2 +H2O=H2CO3=H+ + HCO3
when taking inhaled glucocorticoids pt should be warned to
rinse mouth, b/c of association with oropharyngeal candidiasis
which gas is major stimulator of respiration?
PaCO2
what happens to respiratory drive in prolonged hypercapnea? why should physicians be careful to replenish O2 in these pts
drive to breath is stimulated by hypoxia b/c hypercapnia no longer stimulates the respiratory drive
-rapid increased in the fraction of inspired O2 can lead to respiratory failure in these patients.
minute time vs alvelolar ventilation equations
minute vent= tidal vol* RR
alv=(TV-dead space vol) *RR
infection that causes cold agglutins resulting in agglutination at low temps
mycoplasma pneumoniae,
EBV
and hematology malignancy
phosphatidylcholine and phosphatidylglycerol are components of? which rises more sharply after 30 wks? 36 wks? which is known as lecithin and used in an pulmonary function ratio? value of ratio?
surfactant-dipalmitoyl phophatidylcholine aka lecithin (L)-phosphatidylglycerol-lecithin/sphingomyelin ratio should be above 2 for adequate surfactant production
which bacteria have polysaccaride capsules and can have their capsule components be bound to protein carriers to be used as a vaccine.
streptococcus pneumoniae, neisseria meningitidis, and Haemophilus influenzae type b (Hib)
commonly bound to diphtheria toxoid
lamellar bodies of type II pneumocytes-action, complication if deficient, example
store and release surfactant, deficiency can cause patchy alveolar atelectasis as is seen in neonatal respiratory distress syndrome
which measurement is resistance to outliers in a dataset
mode
structures in bronchi vs terminal bronchioles (globlet cells, cartilage, smooth muscle, pseudostratified ciliated columnar cells)
- cartilage and goblet cells extend to end of bronchi
- pseudostratified columnar ciliated epithelium extend to beginning of terminal bronchi then transition to cuboidal cells
- smooth muscle extend to end of terminal bronchi
treatment for severe asthma if oral and inhaled steroids and long acting beta agonist don’t work? not H1 histamine receptor antagonist because?
- give anti IgE antibodies-Omalizumab (IgG1 antibody that binds IgE to inhibit it’s action on mast cells)
- treats chronic urticaria and allergic symptoms but not asthma
proteases in intra-alveolar fluid are derived from what pulmonary cell
alveolar macrophages or infiltrating neutrophils. can cause emphysema if secretion is unchecked by anti-trypsin
Clara cells secrete? purpose of this secretory product?
clara cell secretory protein (CCSP)-inhibits neutrophil recruitment and activation
prolonged ACTH stimulation causes hyperplasia to what level of adrenal gland? why not hypertrophy?
- zona fasciculata and reticularis
- hyperplasia not hypertophy is primary feature of increased ACTH
condition associated with hyperplasia of
- glomerular layer
- fasciculate/reticularis layer
- adrenal medulla
- atrophy of cortex
- Conn’s syndrome (increased aldo)
- Cushing’s syndrome (increased cortisol)
- rare-pheochromocytoma or neuroblastoma can sometimes occur here
- Addison’s disease. medulla is spared
why is fructose rapidly metabolized in glycolytic pathway?
b/c it bypasses PFK-1 which is rate limiting step in glycolysis.
fructose-fructose 1-phosphate (via fructokinase)
F-1-P to dihydroxy acetone phosphate (DHAP) and glyceraldehyde (aldolase B)
glyceradehyde to G3P (via trioskinase)
galactose enters glycolysis where? mannose?
-glucose 6 phosphate-fructose 6 phosphate
4 major causes of hypoxemia (low PaO2)? what is A-a gradient used for? normal value
alveolar hypoventilation, ventilation-perfusion mismatch, diffusion impairment, and right to left shunting
-if normal than alveolar hypoventilation is only reason for hypoxemia (normal 10-15; PAO2-paO2)
how are macrophages activated? describe their role in granuloma creation?
T- helper cells produce IFN-gamma to mature macrophages. macrophages produce TNF to recruite monocytes. monocytes differentiate into epithelioid histiocytes to cluster around invading pathogen.
Potter syndrome
pulmonary hypoplasia Oligohydraminios (trigger) Twisted facies (low set-ears, retrognathia) Twisted skin Extremity defects Renal agenesis
hyper IgM syndrome-def, causes (2)
inability of B-lymphocytes to class switch from IgM to other isotypes (IgD, IgG, IgE, IgA genes are arranged in this order on DNA) -genetic absence of CD-40 ligand on T-lymphocytes or deficiency in enzymes responsible for DNA modification in isotype switching
most common mutation in cystic fibrosis
3-base pair deletion that removes phenylalanine at a.a position 508. leads to mistakes in postranslational protein modifications causing early degredation of protein before is can be transported to the cell surface.
pt with bacterial pneumonia secondary to viral infection has what bacteria? not listeria monocytogens because
- listeria monocytogens is a occasional cause of septicemia and purulent meningitis in neonates
- pathogens most often responsible are Strep pneumo, staph aureus, and haemophilis influ
s.pneumoniae is sensitive to optochin and? appearance on gram stain?
bile.
- “lancet-shaperd gram positive diplococci”
name 5 materials needed to perform PCR
DNA template, 2 primers (must know flanking sequence not entire sequence to make these), DNA polymerase (thermostable ones like Taq), deoxynucleotide triphosphates
measurement used to determine alveolar ventilation-normal, if decreased, if increased, equation
- PaCO2 (normal 33-45mmHg)
- hyocapnia implies hyperventilation
- hypercapnia implies hypoventilation
- PaCO2=basal metabolic rate/alveolar ventilation
when is pulmonary vascular resistance the lowest? not at end of maximal expiration or maximal inspiration because?
- functional residual capacity (at end of normal expiration) (balance between intra and extra alveolar blood vessels)
- end of maximally expiration compress extra-alveolar blood vessels by reducing radial traction (force opening vessels from extra cellular space) from adjacent tissues
- end of maximal inspiration compresses interstitial alveolar blood vessels
overview of legionella pneumonia clinical features (4) lab findings (3) diagnosis (1) treatment (2)
-high fever with relative bradycardia
-HA and confusion
-watery diarrhea*
lab -hyponatremia, sputum stain with many neutrophils by no organisms
diagnosis
-legionella urine antigen test
-respiratory fluoroquinolones (levofloxacin) or macrolides (azithromycin)
ratio of CD4+/CD8+ in sarcoidosis vs interstitial lung disease vs lymphocytic interstitial pneumonitis (AIDS pts)
these three diseases have similar presentations
can use bronchoalveolar lavage to rule out sarcoidosis
-CD4+/CD8+ ratio is increased in sarcoidosis (granulomas) but decreased in the other two diseases
organ most likely removed during laparotomy in pt with abdominal trauma from motor vehicle accident? pt is susceptible to which type of infection?
spleen from splenic rupture. pt is susceptible to encapsulated species (SHiN bacteria)
what factor affects cerebral blood flow?
PCO2 , decrease cerebral vascular resistance leading to increased cerebral perfusion and ICP.
which nerve mediates cough reflex? location? damaged how?
internal laryngeal nerve
above vocal cords, deep to piriform recess
-foreign bones (fish, chicken) can cause damage or efforts to retrieve them
abestos exposure leads to increased risk of? which is more likely? HY!!
- bronchogenic carcinoma and mesothelioma
- bronchogenic carcinoma!!!
which antibiotics cause bacteria to lose the ability to survive osmotic stress?
the ones that attack the cell wall. penicillins, cephalosporins, vancomyocin
name P-450 inhbitiors- what is mnemonic?
A cute gentleman “Cipped” Iced Grapefruit Juice Quickly And Kept Munching on Soft Cinammon Rolls
Acute alcohol abuse, gemfibrozil, ciprofloxacin, isoniazid, grapefruit juice, quinidine, amiodarone, ketoconazole, macrolides, sulfonamides, cimetidine, ritonavir
which antibiotics work by degrading cell wall. which bugs is resistant to them? treat instead with what?
- penicillins, cephalosporins, carbapenems, and vanc
- all organisms of mycoplasma genus
- treat instead with anti-ribosomal agents (tetracycline and erythromycin)
when should advanced car planning for end of life issues be discussed?
- best during outpatient visits with primary care docs
- must also be readdressed during admission process for acute admissions
- pt with multiple co-morbidities after completing history, physical and stablization
how to treat individuals with IL-12 receptor deficiency?
- IL-12 is required for T-helper cell transformation to TH1.
- TH! then secretes IL-12, IFN-gamma and lympotoxin beta to activate mac, CD8+ Tcells and mediate delayed type hypersensitivity
- so give IFN gamma
histological appearance of bronchioloalveolar carcinoma. benign or malignant? location? pt pop
- tall columnar cells that line alveolar septa without evidience of vascular or stromal invasion
- malignant
- lung periphery
- nonsmoker
most common benign lung tumor? presentation? histo?
- hamartomas
- asymptomatic
- mature hylaine cartilage mixed with connective tissue, smooth muscle, and fat
what happens 1 wk after TB infection. not epithelioid transformation of monocytes b/c? what else happens during this time?
- intracellular bacterial proliferation that due to phagocytosis by macs
- granuloma formation doesn’t occur without signaling (interferon release) form T-helper (type 1) cells which come 2-4 wks after initial infection this created ghon focus
- b cell are activated by TH2 helpers cells to make antibodies but they are not as effective as TH! signaling
types of pneumonia
- bronchopneumonia-patchy inflammation of a number of lobules
- interstitial-inflammatory infiltrate confined to alveolar walls
- lobar-entire lung
stages of lobar pneumonia
-congestion (1st 24 hrs)
red hepatization (2-3 days)
gray hepatization (4-6 days)
resolution
describe macro and micoscopic appearance of congestion red hepatization gray hepatization resolution
- macro:affected lobe is red, heavy and boggy. micro: vascular dilation, alveolar exudations contain bac
- macro: red-firm lobe,like liver. micro: alvelolar exudate has RBCs, neutrophils, and fibrin
- macro: gray-brown firm lobe micro: RBCs disintegrate, alvelolar contains neutrophils and fibrin
- macro: restoration of normal architecture micro: enzymatic digestion of exudate
presentation of anaphylaxis. marker for mast cell activation? not 5-hydroxyindoleacetatic acid b/c
- urticaria, with or w/o cutaneous angioedema, laryngeal edema (causing dyspnea)
- tryptase
- this is breakdown product of serotonin used to screen for carcinoid tumors
treatment for pt with PHTN not due to diabetes or CHF. mech?
anything that will vasodilate vessels
-bosentan is a competitive antagonist of endothelin receptors used for treatment of primary (idiopathic pulm arterial HTN)
etanercept-mech, uses (3)
humanized monoclonal antibody that binds TNF thereby decreasing its concentration in serum
-anti-inflammatory agent used for RA, psoriasis, and psoriatic arthritis
PE leads to what metabolic disturbance?
- hypoxemia leads to hyperventilation causing decreased CO2 and O2 and metabolic alkalosis
- bicarb compensates late and determines pH
normal ranges for PaO2, PaCO2, HCO3-
- 80-95
- 35-45
- 22-26
an unaffected individual with sibling with an autosomal disease has what chance of passing on allele to offspring? not 2/4 because?
2/3 chance of being a carrier. not 2/4 b/c we already know that person is does not have disease so that only leaves 3 options not 4.
which ion is used to determine cause of metabolic alkalosis? what are expected levels in 3 types?
- urinary Cl
- vomiting (decreased urinary Cl; can be corrected with saline)
- loop diuretics and furosemide (increase urinary Cl (follows Na+); can be corrected with saline and chloride)
- primary hyperaldosteronism (Conn syndrome) (increased urinary Cl concentration; does not correct with chloride or saline)
- role of antibiotic in protein syntheis
- streptomycin
- chloramphenicol
- clindamycin/erythromycin
- tetracycline
- aminoglycosides
- linezolid
- binds 30S and prevents formation of initation complex (can also cause misreading of RNA)
- binds 50S aminoacyl-tRNA binding
- bind 50S and prevent translocation
- binds 30S and prevent amionacyl-RNA to A site binding
- binds 50S and blocks binding of initiator tRNA (step before aminoglycoside)
HR and BP in tension pneumothorax, location of lung apices
- above level of clavicle and first rib through superior thoracic aperture (lateral to manubrium sterni)
- HR increases, BP decreases
how to injury ansa cervicalis? carotid body? not near clavicle b/c
- trauma to neck superior to cricoid cartilage
- this lies at birfircation of CCA just inferior to hyoid bone
- trauma near clavicle can lead to pneumothorax
multiple linear regression
used to compare linear relationship between a dependent variable and 2 or more independent variables
what give elastin it’s plasticity and ability to recoil upon release of tension?
- demosine crosslinking between 4 different lysine residues on four different elastin chains
- accomplished by action of extracellular lysl hydroxylase
compare and contrast elastin and collagen
- both have non polar residues
- collagen proline and lysine are hydroxlyated while elastin is not
- triple helix is formed in collagen but not in elastin
- triple helix is initiated by hydroxylation, glycosylation, and interchain disufide bridges at C-terminus of procollagen. these modifications are not seen in elastin molecules
- collagen crosslinking is mediated by lysyl oxidase and elastin crosslinking is mediated by lysyl hydroxylase
which anti TB drug works best in acidic environment
pyranzinamide
- works intracellularly (inside macs where it’s acidic)
- other anti-TB drugs work better extracellularly
which viruses utilize eukaryotic ribosomes for protein synthesis by production of a polyprotein product from a single mRNA transcript?
-positive sense mRNA, which non segmented genomes (picorno, calci, hepes, flavi, toga, retro, corona)
which anti TB drug needs catalase-peroxidase to be active? coded by which gene? mech of drug?
- isoniazid
- KatG
- decrease synthesis of mycolic acids
equation for ARR
event rate (control)-event rate (treatment)
levels of HCO that indicate acute vs chronic respiratory acidosis
30 chronic
-usually take 3-5 days to have maximal effect
location of left ventricle vs other heart chambers vs lung
- reaches as far at 5th intercostal space at left midclavicular line
- all other chambers lie medical to left clavicular line.
- lungs overlap much of anterior surface of heart
spec and sens of methacholine challenge test
- test for asthma
- high sensitive but low spec
- good for ruling out?