Pathology - respiratory

Question 1

Bacterial rhinosinusitis superimposed on viral URI

Answer 1

S. pneumo
H. flu
Morazella catarrhalis

Question 2

Keisselbach plexus vs. posterior segment of nostril

Answer 2

Benign vs. life-threatening hemorrhages (which come from sphenopalatine artery, a branch of the maxillary artery)

Question 3

Origin of DVTs

Answer 3

proximal deep veins of lower extremitiy

dorsiflexion of foot = calf pain

use heparin for short term ppx and tx, then warfarin/rivaroxaban for long term tx

Question 4

Pathophysiology of pulmonary emboli

Answer 4

V/Q mismatch –> hypoxemia –> respiratory alkalosis

Lines of Zahn - interdigitating lines of pink (platelets/fibrin) and red (RBCs) found only in thrombi formed BEFORE death (indicates a pre-mortem thrombus)

Question 5

6 types of emboli in PE

Answer 5

Fat, Air, Thrombus, Bacteria, Amniotic fluid, Tumor (FATBAT)

fat - long bone injury
amniotic fluid - seen w/ DIC
air - ascending divers

Question 6

PFTs in obstructive lung disease

Answer 6

decr. FEV1/FVC ratio***

decr. FEV1 (airways close prematurely at high lung volumes)

Question 7

Hyperplasia of mucus-secreting glands in bronchi

Answer 7

Chronic bronchitis (b = blue bloater)

Reid index = thickness of bronchial wall, >50%

cough: 3 mos/yr, for >2 yrs

Question 8

Enlargement of air spaces, decr. recoil, decr. diffusion capacity for CO, destruction of alveolar walls

Answer 8

Emphysema (p = pink puffer)

incr. elastase activity = loss of elastic fibers

exhalation through pursed lips = incr. airway pressure, prevent airway collapse

Question 9

Two main aspects of asthma

Answer 9

Bronchial hyperresponsiveness –> bronchoconstriction

Smooth muscle hypertrophy

Look for mucus plugging, pulsus paradoxus, decr. I:E ratio

Question 10

Chronic necrotizing infection of bronchi

Answer 10

Bronchiectasis

Permanently dilated airways, purulent sputum, recurrent infections, hemoptysis

Question 11

PFTs in restrictive lung disease

Answer 11

normal FEV1/FVC ratio

decr. FVC

Question 12

Etiologies of restrictive lung disease

Answer 12

1. ) poor breathing mechanics (normal A-a gradient)

2. ) interstitial lung disease (decr. diffusion capacity, incr. A-a gradient)

Question 13

Hypersensitvity pneumonitis

Answer 13

Type III/IV rxn

Question 14

Cor pulmonale, Caplan syndrome (RA + intrapulmonary nodules)

Answer 14

signs of pneumoconioses

Question 15

Supradiaphragmatic and pleural plaques

Answer 15

Asbestosis

incr. risk of cancer (bronchogenic carcinoma > mesothelioma)

absestos bodies = golden-brown rods that look like dumbbells, found in sputum

Question 16

Macrophages laden with carbon, inflammation and fibrosis

Answer 16

Coal workers’ pneumoconiosis

Upper lobes affected

anthracosis - similar, but found in urban people with pollution

Question 17

Mechanism of silicosis

Answer 17

Macrophages respond to silica and release fibrogenic factors, leading to fibrosis. Eggshell calcification of hilar lymph nodes

Affects upper lung lobes

Silica may disrupt phagolysosomes and impair macrophages, incr. susceptibility to TB! also, incr. risk of bronchogenic carcinoma

Question 18

Therapeutic O2 in neonatal RDS complications

Answer 18

1. ) retinopathy
2. ) intraventricular hemorrhage
3. ) bronchopulmonary dysplasia

Question 19

Risk factors for neonatal RDS

Answer 19

Prematuriy, maternal diabetes, C-section delivery

Lecithin:sphingomyelin ratio <1.5

Persistently low O2 levels can lead to risk of PDA

Question 20

Damage mediators in ARDS

Answer 20

1. ) neutrophils
2. ) activation of coagulation cascade
3. ) oxygen-derived free radicals

lead to diffuse alveolar damage, leading to incr. alveolar capillary permeability, then protein-rich leakage into alveoli and pulmonary edema

Question 21

Vascular changes in pulmonary hypertension

Answer 21

Arteriosclerosis
Medial hypertrophy
Intimal fibrosis of pulmonary arteries

Question 22

Causes of pulmonary artery hypertension

Answer 22

***hereditary: BMPR2 gene, normally inhibits vascular smooth muscle proliferation

Question 23

Increased fremitus

Answer 23

consolidation!

lobar pneumonia, pulmonary edema

Question 24

Hyperresonant breath sounds

Answer 24

Pneumothorax

Question 25

TGs in pleural fluid

Answer 25

Lymphatic pleural edema (chylothorax)

thoracic duct injury from trauma or malignancy

Question 26

Atypical pneumonias

Answer 26

Viruses, mycoplasma, legionella, chlamydia

diffuse patchy inflammation localized to interstitial areas at alveolar walls

Question 27

Two causes of lung abscess

Answer 27

Aspiration of oropharyngeal contents

Bronchial aspiration

Question 28

Face/arm edema, JVD, swollen collateral veins on chest, shortness of breath, coughing

Answer 28

SVC syndrome, sometimes seen with Pancoast tumor

Medical emergency, can lead to headaches, dizziness, rupture of aneurysm/intracranial arteries (incr. ICP)

Question 29

Lung cancer complications

Answer 29

SPHERE: SVC syndrome, Pancoast tumor, Horner, Endocrine, Recurrent laryngeal nerve compression, Effusions

Question 30

Two centrally located lung cancers

Answer 30

Squamous cell

Small cell

Question 31

Three main neoplastic syndromes with small cell lung cancer

Answer 31

ACTH - Cushing syndrome
SIADH
Abs against pre-synaptic Ca channels - Lambert-Eaton

Look for neuroendocrine cells - Kulchitsky cells

Question 32

Lung cancer assoc. w/ clubbing, glandular pattern on histology

Answer 32

Adenocarcinoma

activating mutations: KRAS, EGFR, ALK

Question 33

Lung cancer w/ cavitation, cigarettes, hypercalcemia (PTHrP)

Answer 33

squamous cell carcinoma

hilar mass arising from bronchus

look for keratin pearls and intercellular bridges

Question 34

Highly anaplastic undifferentiated lung cancer

Answer 34

Large cell carcinoma

pleomorphic giant cells, can secrete b-hCG

Question 35

Phases of lobar pneumonia

Answer 35

congestion –> red hepatization –> gray hepatization –> resolution

Question 36

Progression of tuberculous infection

Answer 36

Granulomatous with caseous necrosis

Caseous: T-cell mediated delayed hypersensitivity (Th1 stimulation of macs and CD8 T cells)