Respiratory system

Question 1

at what week in utero does pneumocytes start to develop?

Answer 1

week 26 up until birth

Question 2

embryo pathogenesis of bronchogenic cysts?

Answer 2

caused by abnormal budding of the foregut and dilation of terinal or large bronchi

Question 3

what are club cells (aka clara cells)?

location? function?

Answer 3

nonciliated, low comunar/cuboidal cells with secretory granules.
located from bronchioles to respiratory bronchioles
fx: secrete component of surfactant, degrade toxins, act as reserve cells

Question 4

most important lecithin in surfactant?

Answer 4

DPPC. Dipalmitoylphosphatidylcholine

Question 5

Supplemental O2 of infant can result in: RIB

Answer 5

Retinopathy/blindness
Intraventricular hemorrhage
Bronchopulmonary dysplasia

Question 6

what value on L/S ratio in amniotic fluid is predictive of NRDS? (neonatal respiratory distress syndrome)

Answer 6

Lecithin : Sphingomyelin ratio.
2+ is healthy
<1.5 is predictive of NRDS

Question 7

2 complications of neonatal respiratory distress syndrome?

Answer 7

PDA (b/c of less O2 tension)

necrotizing enterocolitis. idk why

Question 8

increase in what things results in right shift/decreased Hb O2 affinity? (5)

Answer 8

increased Cl-, H+, CO2, 2,3-BPG, temperature

Question 9

how is it that fetal Hb (2alpha, 2gamma) has higher affinity for O2 than adult Hb, thereby driving diffusion of O2 across placenta from mother to fetus?

Answer 9

b/c it has decreased affinity of 2,3-BPG

Question 10

is taut form or relaxed form of Hb increased or decreased O2 affinity

Answer 10

taut form -> right shift -> decreased O2 affinity

relaxed form = left shift = increased O2 affinity

Question 11

How do you induce methemoglobinemia (to treat CN- poisoning)?

how to treat methemoglobinemia?

Answer 11

induce: nitrites followed by thiosulfate
treat: methylene blue and vitamin C

Question 12

Nitrates cause CN poisoning but what other drug does too?

Answer 12

Benzocain (thiosulfate does too but i guess it’s not a drug in and of itself?)

Question 13

pt comes in with cyanosis and chocolate covered blood. dx?

Answer 13

methemoglobinemia

Question 14

posterior nose bleeds are from _____ artery, a branch of _____ artery

Answer 14

sphenopalatine artery. branch of maxillary artery

Question 15

Virchow’s triad of thrombosis: SHE

Answer 15

Stasis
Hypercoagulability
Endothelial damage

Question 16

HPV is associated w/ what type of cancer?

Answer 16

oropharyngeal

Question 17

what lab test has high sensitivity to rule out DVT?

Answer 17

D dimer

Question 18

where does CO2 bind to Hb?

Answer 18

N terminus

whereas O2 binds to heme part

Question 19

what type of hypersensitivity rxn is Hypersensitivity penumonitis?

Answer 19

MIXED type III/IV

Question 20

patient comes in with diffuse fibrosis, intrapulmonary nodules, pneumoconiosis, and RHEUMATOID ARTHRITIS.
what do they have?

risk factor?

Answer 20

Caplan syndrome = pneumoconiosis + RA

coal workers! carbon dust. can also get from silica and asbestos exposure, but mainly coal/carbon dust.

Question 21

location in lung of the 4 pneumoconioses

Answer 21

Asbestosis is in base of lungs (it was used in roofing, but is located in base of lungs)

other 3 are in upper lobes of lungs

Question 22

Pneumoconioses:

noncaseating granulomas in lung, hilar lymph nodes, and systemic organs

Dx and increased risk for what?

Answer 22

Berylliosis, seen in aerospace industry workers

increased risk for lung cancer.

Question 23

Pneumoconioses: eggshell calcification of hilar lymph nodes. fibrotic nodules in upper lobes

Dx and increased risk for what?

Answer 23

Silicosis. seen in sandblasters and silica miners and those casting metal

increased risk for TB, since silica impairs phagolysosome formation by macrophages.

Question 24

fibrosis of lung AND PLEURA (ivory white calicified plaques), lower lobes. may have golden brown fibers associated w/ iron

Dx? seen in who?
and increased risk for what?

Answer 24

Asbestosis

shipyard and construction workers, plumbers, roofing

inc risk for bronchiogenic cancer > mesothelioma (cancer of pleura

Question 25

what is Anthracosis

Answer 25

when only mild exposure to carbon -> collections of carbon laden macrophages. not clinically significiant

Question 26

what 2 things are present in Mesotheliomas? is smoking a risk factor?

Answer 26

``` Psamomma bodies on histology calretinin positive (negative in most carcinomas) ``` smoking is NOT a risk factor!

Question 27

what gene is mutated in familial pulmonary HTN? what is its function?

Answer 27

BMPR2 gene mutated (inactivated). normally inhibits vascular SM proliferation

Question 28

pt has decreased breath sounds, dull percussion, decreased tactile fremitus. +/- tracheal deviation away from side of lesion

Answer 28

Pleural effusion

Question 29

pt has decreased breath sounds, dull percussion, decreased tactile fremitus. tracheal deviates toward side of lesion

Answer 29

Atelectasis (bronchial obstruction)

Question 30

pt has decreased breath sounds, hyperresonant percussion, decreased tactile fremitus.

Answer 30

pneumothorax note: trachea deviates TOWARDS spontaneous pneumothorax (collapsed lung), and AWAY from tension pneumothorax (air in pleural space)

Question 31

increased tactile fremitus

Answer 31

consolidation (pneumonia, edema)

Question 32

natural history of lobar pneumonia days 1-2: days 3-4: days 5-7: days 8+

Answer 32

days 1-2: congestion. red-purple. exudate w/ mostly bacteria days 3-4: red hepatization. red/brown. exudate w/ fibrin, bacteria, RBCs, WBCs days 5-7: gray hepatization. exudate full of WBCs and fibrin days 8+: resolution. enzymes digest components of exudate

Question 33

looks like SVC syndrome but unilateral. which structure is compressed?

Answer 33

brachiocephalic vein

Question 34

horner syndrome can occur from invasion of cervical sympathetic chain by pancoast tumor, but can also occur from compression of what?

Answer 34

Stellate ganglion

Question 35

where does lung cancer like to metastasize to? (4)

Answer 35

adrenals, brain, bone (pathologic fracture), liver (jaundice, hepatomegaly)

Question 36

metastasis to lung is more common than primary lung neoplasms. most common primary sites? (4)

Answer 36

breast, colon, prostate, bladder

Question 37

Amplication of what oncogenes is common in small cell/oat cell lung carcinoma?

Answer 37

myc oncogenes

Question 38

small cell/oat cell lung carcinoma is a neoplasm of what kind of cells? stain positive for? location in lung?

Answer 38

neuroendocrine Kulchitsky cells -> small dark blue cells chromogranin A positive, neuron-specific enolase positive located in central portion of lung

Question 39

adolescent male comes in with profuse nose bleeds. what is the most likely cause?

Answer 39

angiofibroma: benign tumor of nasal mucosa composed of large blood vessels and fibrous tissue

Question 40

EBV -> nasopharyngeal carcinoma w/ enlarged cervical lymph nodes. what biopsy and stain of the carcinoma show?

Answer 40

"pleomorphic keratin-positive epithelial cells (poorly differentiated squamous cell carcinoma) in a background of lymphocytes"

Question 41

myxoid/degenerative connective tissue on true vocal cords (usually bilaterally) what is it?

Answer 41

singer's nodule. just need to rest voice

Question 42

2 modifiable risk factors for laryngeal carcinoma

Answer 42

alcohol and smoking

Question 43

2 most common causes of lobar pneumonia

Answer 43

Strep pneumo | Klebsiella pneumo

Question 44

common organisms causing 2ndry pneumonia, community acquired, and pneumonia superimposed on COPD

Answer 44

Haemophilus influenzae Moraxella catarrhalis Legionella

Question 45

2 complications of mycoplasma pneumoniae | what groups of ppl are at higher risk?

Answer 45

affects young adults. military recruits and college students in living in dorm complications: autoimmune cold hemolytic anemia (IgM against I antigen on RBCs) ; erythema multiforme

Question 46

pneumonia + hepatitis

Answer 46

Q fever | coxiella burnetii

Question 47

PiZZ homozygotes are at significant risk for what?

Answer 47

panacinar emphysema (A1AntiTrypsin deficiency), and cirrhosis

Question 48

lay out the immuno pathway of asthma what type of hypersensitivity rxn is it?

Answer 48

type I hypersensitivity - Th2 CD4 helper cells. IL4,5,10 - reexposure to allergen -> IgE mediated activation of mast cells - early rxn = histamine, leukotrienes - delayed rxn = eosinophils release MBP

Question 49

mediator of idiopathic pulmonary fibrosis pathogenesis

Answer 49

TGF-beta from injured pneumocytes induces fibrosis

Question 50

immune mediators of sarcoidosis

Answer 50

TH1 cells, secrete IL-2 and IFN-gamma

Question 51

causes of bronchiectasis (5)

Answer 51

1. cystic fibrosis 2. Kartagener syndrome/primary cilia defective (dynein) 3. foreign body 4. necrotizing infection 5. allergic bronchopulmonary aspergillosis

Question 52

why do you get hyper vit D-> hypercalcemia in sarcoidosis?

Answer 52

1-alpha hydroxylase activity of epithelioid histiocytes of granulomas converts vitamin D to its active form

Question 53

what cell mediates ARDS?

Answer 53

neutrophils. release protease and ROS to damage pneumocytes -> intra-alveolar hyaline membrane formation

Question 54

the 3 main risk factors of lung cancer

Answer 54

1. cigarette smoke (polycyclic aromatic hydrocarbons and arsenic esp) 2. radon (accumulates in closed spaces e.g. basements, uranium miners at risk) 3. asbestos (shipyard workers, roofing, plumbing, construction workers)

Question 55

which lung cancer can produce PTHrP? (-> hypercalcemia)

Answer 55

squamous cell carcinoma male smokers keratin pearls or intercellular bridges of desmosomes on histology central lung

Question 56

the official term for digital clubbing

Answer 56

hypertrophic osteoarthropathy

Question 57

what can small cell lung carcinoma cause besides paraneoplastic stuff and lambert eaton syndrome?

Answer 57

can produce neurons -> paraneoplastic nyelitis, encephalitis, subacute cerebellar degeneration

Question 58

"polyp like mass in the bronchus"

Answer 58

carcinoid tumor. chromogranin positive

Question 59

which lung cancer is more peripherally located and can metastasize to involve pleura

Answer 59

adenocarcinoma (but large cell carcinoma and carcinoid tumor can also be peripheral, those can be anywhere)

Question 60

EGFR mutation in lung cancer (adenocarcinoma) is commonly seen in what group of ppl? tx?

Answer 60

Asian females | tx: erlotinib

Question 61

ALK translocation in lung adenocarcinoma. tx?

Answer 61

crizotinib

Question 62

PD-L1 expression in a non-small cell lung carcinoma. tx?

Answer 62

pembrolizumab

Question 63

tumor encasing lung = mesothelioma. biggest risk factor?

Answer 63

asbestos

Question 64

Sildenafil treats pulmonary HTN and erectile dysfunction. MOA?

Answer 64

inhibit PDE-5 -> increase cGMP -> prolong NO effect

Question 65

major side effect of bosentan, an endothelin-1 receptor antagonist used for pulm HTN?

Answer 65

hepatotoxicity. increased LFE's

Question 66

PGI2 analogs (2)

Answer 66

Epoprostenol, iloprost

Question 67

Pt is using Dextromethorphan as an antitussive (antagonizes NMDA glut receptors). what 2 things do u need to look out for?

Answer 67

1. can act like opioid in over dose -> treat with Naloxone | 2. serotonin syndrome if combined w/ other drugs

Question 68

MOA of Montelukast, zafirlukast, and Zileuton

Answer 68

Zileuton = inhibit 5-LOX Montelukast, Zafirlukast = leukotriene receptor blockers (CysLT1)

Question 69

Theopylline (a methylxanthine) MOA

Answer 69

inhibit PDE -> increase cAMP-> bronchodilation. also blocks action of adenosine used for asthma/lung stuff

Question 70

Is Methacholine M1, M2, or M3 agonist?

Answer 70

M3 (smooth muscle)

Question 71

where are M1, M2, and M3 receptors found?

Answer 71

M1 is brain M2 is heart M3 is glands and SM

Question 72

Omalizumab MOA

Answer 72

binds unbound serum IgE and blocks binding to FceRI. good for atopic asthma where IgE level is high