Respiratory Pathology Flashcards
Pulmonary Embolism
-Fat: associated w/ long bone fx & liposuction
-Air: injection
-Thrombus
-Bacteria
-Amniotic Fluid: Can lead to DIC post-partum
-Symptoms: Chest pain, tachypnea, and dyspnea
-About 95% arise from deep leg veins
-Diagnose w/ D dimer and Helical CT
-Tumor
-
Deep Vein Thrombosis
- Predisposed by Virchow’s Triad:
- Stasis
- Hypercoagulability: defect in coagulative cascade proteins
- Endothelial damage: exposed collagen=clotting cascade
- Can lead to pulmonary embolism
- Homan’s sign: dorsiflexion of foot
- Tender calf muscle
Obstructive Lung Disease (COPD)
- Obstruction of air flow
- Results in air trapping in lungs
- Airways close prematurely at high lung volumes
- Increased residual volume
- Decreased Forced Vital Capacity
- Substantial decrease in Forced expiratory Volume 1
- Decreased FEV1/FVC ratio <80%
Chronic Bronchitis
- Blue bloaters
- Hypertrophy of mucus-secreting glands in bronchioles
- Reid Index: gland depth/total bronchial wall thickness
- In COPD Reid index >50%
- Productive cough >3 consecutive months in >2years
- Disease of small airways
- Findings:
- Wheezing and crackles
- Cyanosis (early hypoxemia due to shunting)
- Late onset dyspnea
Emphysema
- Pink Puffers
- Barrel-shaped chest
- Enlarged air spaces
- Decreased recoil
- Due to destruction of alveolar walls
- Increased compliance
- Increased elastase activity
- Increased lung compliance due to loss of elastic fibers
- Exhale thru pursed lips to increase airway pressure & prevent airway collapse
Asthma
- Bronchial hyperresponsiveness
- Causes reversible bronchoconstriction
- Smooth muscle hypertrophy
- Curschmann’s Spirals: shed epithelium from mucus plug
- Can be triggered by viral URI, Allergens and stress
- Test w/ methacholine challenge
- Findings: cough, wheezing
- tachypnea, dyspnea, hypoxemia
- Decreased I/E ratio
- Pulsus paradoxus
- Mucus plugging
Bronchiectasis
- Chronic necrotizing infection of the bronchi
- Permanently dilated airways
- Purulent sputum
- Recurrent infections
- Hemoptysis
- Associated w/ bronchial obstructions, poor ciliary motility
- Kartagener’s syndrome
Restrictive Lung Disease
- Decreased Lung Volumes
- Decreased FVC and Decreased TLC
- FEV1/FVC ration > 80%
- Poor breathing mechanics
- Poor muscular efforts: polio, myasthenia gravis
- Poor structural apparatus: scoliosis, morbid obesity
- Interstitial Lung Disease
- ARDS
- Neonatal RDS (Hyaline membrane disease)
- Pneumoconioses
- Sarcoidosis
- Idiopathic pulmonary fibrosis
- Goodpasture’s Syndrome
- Wegener’s granulomatosis
- Eosinophilic granuloma
- Drug toxicity
Coal Miner’s Pneumoconioses
- Associated w/ coal mines
- Can result in cor pulmonale
- Caplan’s syndrome: combo w/ rheumatoid arthritis
- Affects upper lobes
Silicosis
- Associated w/ foundries, sandblasting, and mines
- Macrophages respond to silica
- Release fibrogenic factors-> Fibrosis
- Silica may disrupt phagolysosomes & & impair macrophages
- Increases susceptibility to TB
- Affects upper lobes
- Eggshell calcification of hilar lymph nodes
Asbestosis
- Associated w/ ship building, roofing, & plumbing
- Results in ivory white calcified pleural plaques
- Increased incidence of bronchogenic carcinoma and mesothelioma
- Affects lower lobes
- Asbestos bodies: golden brown fusiform rods
- resemble dumbbells
- Located inside macrophages
Neonatal Respiratory Distress Syndrome
-Surfactant deficiency
-Leads to increased surface tension
-Alveolar collapse
-Type II pneumoncytes make surfactant at 35th week gestation
-Lecithin:sphingomyelin ratio in amniotic fluid
-Measures lung maturity
<1.5 in neonatal RDS
-Persistent low O2 tension risk of PDA
-O2 can cause retinopathy of prematurity
-Risk Factors: prematurity
-Maternal diabetes (elevated insulin)
-C-section (Decreased fetal glucocorticoids)
-Treatment: maternal steroids before birth
-Artificial surfactant for infant
-Thyroxine
Acute Respiratory Distress Syndrome
- Causes: trauma, sepsis, shock, gastric aspiration, uremia
- Acute pancreatitis or amniotic embolism
- Diffuse alveolar damage leads to Increased capillary permeability
- Protein-rich leakage into alveoli
- Results in formation of intra-alveolar hyalin membrane
- Initial damage due to release of neutrophilic substances
- toxic to alveolar wall
- Activation of coagulation cascade
- Oxygen derived free radicals
- Histology shows alveolar fluid and hyaline membranes
General Lung Cancer
- Presentation: cough, hemoptysis, wheezing
- Bronchial obstruction
- pneumonic ‘coin’ lesion on X-ray
- Noncalcified nodule on CT
- Mets from breast, colon, prostate, & bladder most common
- Mets to adrenal, brain, bone, liver
- Complications:
- Superior vena cava syndrome (bronchogenic carcinoma)
- Pancoast tumor
- Horner’s Syndrome (posis, myosis, anhydrosis)
- Paraneoplastic syndrome
- Recurrent laryngeal symptoms
- Effusions
Small Cell Carcinoma
- Central location
- undifferentiated: very aggressive
- Often ectopic ACTH or ADH
- May lead to Lambert-Eaton Syndrome
- Autoantibodies to calcium channels
- muscle weakness of limbs
- Responsive to chemotherapy
- Inoperable
- Neoplasm of neuroendocrine Kulchitsky cells
- Enterochromaffin cells in epithelium or lungs
- Small dark blue cells
Bronchial Adenocarcinoma
- Peripheral location
- Develops in site of prior pulmonary inflammation/injury
- Most common lung cancer in nonsmoker females
- Clara cells->type II pneumocytes
- Multiple densities on CXR
Bronchioalveolar Adenocarcinoma
- Peripheral location
- Not linked to smoking
- Grows along airways
- Can present like pneumonia
- Can result in hypertrophic osteoarthropathy
- Clara cells->type II pneumocytes
- Multiple densities on CXR
Squamous cell carcinoma
- Central location
- Hilar mass arising from bronchus
- Cavitation
- Clearly linked to smoking
- parathyroid like activity
- Keratin pearls
- Intracellular bridges
Large cell carcinoma
- Peripheral location
- Highly anaplastic undifferentiated tumor
- Poor prognosis
- less responsive to chemo
- Removed surgically
- Pleomorphic giant cells
- Leukocyte fragments in cytoplasm
Carcinoid Tumors
- Secretes serotonin
- Cause carcinoid syndrome
- Flushing, diarrhea, wheezing, salivation
- Fibrous deposits in RT heart valves
- Tricuspid insufficiency
- Pulmonary stenosis
- RT heart failure
Mesothelioma
- Malignancy of pleura
- Associated w/ asbestosis
- Results in hemorrhagic pleural effusions
- pleural thickening
Pancoast Tumor
- Carcinoma in apex of lung
- Affects cervical sympathetic plexus
- Causes Horner’s Syndrome
- ptosis
- Miosis
- Anhidrosis
Superior Vena Cava Syndrome
- Obstruction of SVC
- Impairs blood drainage from the head (Facial Plethora)
- JVD
- Upper Extremity edema
- Caused by neoplasms and thrombosis
- Can raise intracranial pressure
- headaches & dizziness
- Increased risk of aneurysm/ rupture of cranial arteries
Lobar Pneumonia
- S. pneumonia
- Klebsiella
- Intra-alveolar exudate
- Causes consolidation
- May involve entire lung
Bronchopneumonia
- S. aureus
- H. influenzae
- S. pyogenes
- Acute inflammatory infiltrates
- From bronchioles into adjacent alveoli
- Patchy distribution involving more than one lobe
- Neutrophils in the alveolar spaces
Interstitial (atypical) pneumonia
- Viruses: RSV, and adenoviruses
- Mycoplasma
- Legionella
- Chlamydia
- Diffuse patchy inflammation
- localized to interstitial areas of alveolar walls
- Distribution involves >1 lobe
- More indolent course than bronchopneumonia
Lung Abscess
- Localized collection of pus w/in parenchyma
- Caused by:
- bronchial obstruction
- aspiration of oropharyngeal contents (Alcoholics)
- Air-fluid level seen on CXR
- S. aureus or anaerobes
Transudate
- Pleural effusion w/ low protein content
- CHF
- Nephrotic syndrome
- Cirrhosis
Exudate
- Pleural effusion w/ high protein content
- Malignancy
- Pneumonia
- Collagen vascular disease
- trauma in states of increased vascular permeability
- Must be drained in light of risk of infection
Lymphatic Pleural Effusion
- Chylothorax
- Milky appearing fluid
- Increased triglycerides
Spontaneous Pneumothorax
-Accumulation of air in pleural space
-Most frequently in tall thin young males
-Rupture of apical blebs
-Tracheal deviation toward affected lung
-Symptoms:
Chest pain
Dyspnea
Unilateral chest expansion
Decreased tactile fremitus
Hyperresonance
Decreased breath sounds
Tension Pneumothorax
-Usually occurs in trauma or lung infection
-Air capable of entering pleural space but not exiting
-Trachea deviates away from affected lung
-Symptoms:
Chest pain
Dyspnea
Unilateral chest expansion
Decreased tactile fremitus
Hyperresonance
Decreased breath sounds
