B4.057 - Obstructive Pulmonary Disease Flashcards
pulmonary hypertension, a complication of COPD
histo of chronic bronchitis
thick walled bronchi, abundant mucous glants, goblet cell metaplasia, chronic inflammation
what is centriacinar emphysema
central/proximal portions of acini affected (resp bronchioles) but distal alveoli are spared if severe affects entire acinus worse in upper lobes smoking >95% of clinical cases
how does CF cause bronchiectasis
inherited ion transport defect leads to defective mucociliary action and airway obstruction by thick viscous secretions. predisposes to chronic infections causing airway damage and descruction of smooth muscle and elastic tissue
pathogenesis of atopic asthma
complex and mulitfactorial
Th2 and IgE response to environmental allergens in genetically prediosposed individuals
exaggerated Th2 response
left - normal
right - primary ciliary dyskinesia
loss of dynein arms in fibure b
what are the classes of triggers of asthma
seasonal
exercise induced
drug induced
occupational
asthmatic bronchitis in smokers
panacinar emphysema
acini are uniformly enlarged from respiratory bronchiole to alveoli entire acinus, not entire lung worst at bases Alpha1 antitrypsin deficiency
what is emphysema
abnormal permanent enlargement of the airspaces distal to the terminal bronchiole and destruction of their walls without obvious fibrosis, but may see fibrosis in small airways/bronchioles
bronchiectasis
epidemiology of chronic bronchitis
chronic irreversible obstruction of airflow
affects all people all ages
common in longtime smokers, polluted urban areas
more common over 45
more common in men
describe atopic asthma clinical scenario
most common type
begins in childhood
triggers: environmental antignes, dusts, pollens, animal dander, foods
positive family Hx of atopy
allergic rhinitis, urticaria, eczema
environmental factors predisposing to asthma
rhinovirus type C, respiratory syncytial virus
chracot leyden crystals
eosinophils
histo of asthma
represent breakdown products of eosinophils composed of an eosinophil protein called galectin 10
epidemiology of emphysema
men and women, men more common smoking major cause develops gradually clinically significant symptoms at any age, 40+ in smokers although ventilatory deficits seen earlier
sub pleural bullae seen in emphysema
pathogenesis of bronchiectasis
normal clearing mechanisms are impaired –> pooling of secretions distal to the obstruction –> secondary infection and inflammation
CF induced bronchiectasis
what percentage of smokers develop COPD
50%
chronic bronchitis
productive cough of unknown cause, ocurring for 3 or more months in at least 2 successive years
what is the mechanism of disease in emphysema
functional airflow obstruction
normally small airways are tethered open by elastic recoil in the walls of surrounding alveoli
loss of elastic tissue in aleolar walls allows th erespiratory bronchioles to collapse during expiration
inflammation also plays a role
types of emphysema
centriacinar panacinar distal acinar/paraseptal irregular
panacinar emphysema alpha 1 antitrypsin deficiency
ruptured alveolar septae (red arrow)
pathogenesis of emphysema
smoking
increased oxidative stress, inflammatory cells/mediators, protease/antiprotease imbalance
all lead to alveolar wall destruction
bronchiectasis
dilated bronchile wiht stasi of mucus secretions and inflamed walls
surrounding fibrosis
epidemiology of asthma
ocurrs in 5% of pop
any age
most common in children, decreases with puberty, increases with age
increasing incidence
pink puffer
emphysema
barrel chested, dyspneic, prolonged expiration, hunched over position, breathes through pursed lips
centriacinar emphysema
what percentage of people with COPD smoke
80%
blue bloater
chronic bronchitis
cough, DOE, hypercapnea, hypoxemia, mild cyanosis
asthma
chronic disorder of conducting airways, usually caused by an immunological reaction
episodic bronchodilation due to increased airway sensitivity to a variety of stimuli
inflammation of bronchial walls
increased mucus secretion
atopic astham mediated by
IgE type 1 HS
skin test using offentig antigen –> immediate whela and flare reaction
high serum IgE
presence of RAST: detects presence of IgE Abs specific for individual allergens
compare and contrast chronic bronchitis and emphysema
chronic bronchitis
anatomic compartment
etiology
pathogenesis
anatomic compartment - bronchus
etiology - chronic irritation by inhaled substances like tobacco smoke
pathogenesis - hypersecretion of mucous, metaplasia, hypertrophy and remodeling of small airways, inflammation
bronchiectasis
destruction of airway muscle and elastic tissue resulting in permanent dilation of bronchi and bronchioles, often by chronic necrotizing infections
occupational asthma causes
fumes, dusts, gases, other chemicals
repeated exposure to chemicals results in minute quantity stricturing attakcs
mechansism include: T1 reactions, direct reslease of bronchoconstrictors, unknown HS reponses
initiating factors of chronic bronchitis
exposure to noxious inhaled substances: tobacco smoke, dust
mucus hypersecretion in airways (IL13)
inflammation
infection - maintains disease process and causes exacerbations
what is an alpha 1 antitrypsin deficiency and the genetics behind it
loss of an antiprotease that leads to emphysema
PiMM - normal
PiMZ - heterozygous
PiZZ - homozygote - highest risk for emphysema
clinical features of bronchiectasis
cough, expectoration of copious amounts of foul smelling purulent sputum.
hemoptysis
recurrent acute infective exacerbations that can lead to sever lung function and impairment and respiratory failure
dyspnea, wheezing
what is asthma characterized by
bronchial hyperresponsiveness triggered by allergens, infection etc.
distal acinar/paraseptal empysema
distal acinus is predominantly involved adjacent to the pleura, along the septa next to fibrosis, scarring or atelectasis worse in upper lung spontaneous pneumothorax
pts with bronchiectasis are at higher risk of what hypersensitivity
aspergillosis
Th2 recruit eosinophils and other leukocytes
high serum IgE and serum antibodies to aspergillus
goblet cell metaplasia of bronchial epithelium seen in chronic brochitis
what do bc and ad refer to
bc - thicknessof the mucous galnd layer
ad - thickness of the bronchial wall between the epithelium and cartilage
irregular emphysema
acinus is irregularly involved scarring occurs in small foci, is clinically insignificant
symptoms of aspergillosis
inflammation and formation of mucus plugs, which play a primary role in pathogenesis
bronchiectasis
dilated airways with inflamed walls
thickened basement membrane - bottom left
smooth muscle hypertrophy - bottom right
respiratory epithelium - top
green arrowhead - goblet cell hyperplasia
eosinophilic inflammation - yellow arrowhead
seen in asthma
bullae seen in emphysema
susceptibility locus for asthma
chromosome 5q (codes interleukins IL13)
mucus plugs (left)
chronic inflammation in bronchiolar wall (right)
seen in chronic bronchitis
drug induced asthma causes
aspirin (+recurrent rhinitis, nasal polyps)
NSAIDs - inhibit COX pathway decreasing PGE2 –> release inhibition of enzymes that generate pro inflammatory mediators LTs
symptoms of asthma
recurrent episodes of wheezing, breathlessness, chest tightness, cough particulary at night and early morning
at least partly reversible
inflammation causes an increase in airway responsiveness to a variety of stimuli
airway remodeling
thickening of airway wall
hypertrophy and hyperplasia of bronchial wall muslce
obstructive lung diseases cause what and what are some examples
increased resistance to airflow due to partial or complete obstruction at any level Decreased FEV1 emphysema, chronic bronchitis, asthma, bronchiectasis
50% of pts with primary ciliary dyskinesia have what
kartageners syndrome - situs inversus all organs are on flip side
sinusitis
bronchectasis
treatment of bronchiectasis
treat underlying cause
chest physical therapy
antibiotic therapy
panacinar emphysema
unique complication of emphysema
pneumothorax
types of asthma
atopic - evidence of allergen sensitization and immune activation, often with rhinitis and eczema
non atopic - no evidence of allergen sensitization
bronchiectasis
complications of bronchiectasis
cor pulmonale
amyloidosis
metastatic brain abcesses
how do tobacco and infection contribute to chronic bronchitis
tobacco interferes with ciliary action, directly damages airway epithelium, inhibits ability of white blood cells to clear bacteria. Infections maintain but do not initiate chronic bronchitis
causes of bronchiectasis
idiopathic
post infection
congenital - CF, sequstration of lung, ciliary dyskinesia
obstruction of bronchioles
collagen vascular diseaes, inflammatory bowel disease, post transplant
what are bullae
large cystic dilated airspaces seen in emphyema
what is status asthmaticus
acute severe asthma, can be fatal, continuous symptoms
mucus plug - left
surshmann spiral - right - coiled pragment of inspissated mucus
gross
what is the reid index
the ratio and thickness of the mucous gland layer to the thickness of the bronchial wall between the epithelium and cartilage
non atopic asthma causes
triggered by respiratory tract (viral) infection
rhinovirus, parainfluenza, respiratory syncytial viurus
ihaled air pollutantts
cold or exercies
negative skin test
COPD complications
cor pulmonale, HF, pneumothorax (emphysema), superimposed acute infections (CB)
when do symptoms present in emphysema
1/3 of functioning lung parenchyma impaired
how does primary ciliary dyskinesia lead to bronchiectasis
autosoma recessive syndrome
defect in ciliary motor protien dynein which inhibits bacterial clearance in sinuses and airways
