Pulmonary Pathology Flashcards
How much do the lungs weigh?
200-250 grams each
Which lung is slightly larger?
right
True or False: The lungs have a dual blood supply.
True
What are the two sources of blood to the lungs?
pulmonary
bronchial
What is the major function of the lungs?
gas exchange
What is/are involved in the act of respiration?
upper respiratory tract
diaphragm
accessory muscles
neural regulation
Describe the pulmonary defenses of the upper and lower respiratory tract.
upper = filtering function (hairs) lower = mucociliary apparatus (clear debris through wavelike motions)
The vocal cords are lined by _______ epithelium.
stratified squamous
The large airways are lined by _______ epithelium. What are “large” airways?
pseudostratified, ciliated, columnar
larynx, trachea, and bronchi
What do the large airways contain within their walls?
mucus glands (mucosal and submucosal) neuroendocrine cells cartilage
How many types of alveoli are lining the alveolar space? How prevalent are each of them?
Two types:
Type I Pneumocytes (flat) = 95%
Type II Pneumocytes (cuboidal, surfactant) = 5%
Other than hairs and mucociliary mechanisms, how does the pulmonary system protect itself?
- Lymphoid Tissues (in URT and LRT): provides cellular immunity and humoral immunity
- Alveolar Macrophages: collect particles of dust, infectious agents, etc.
What is the humoral immunity that lymphoid tissues provide?
mucosal IgA secretion
How far does cartilage extend through the pulmonary exchange vessels?
Trachea…Bronchi (c-shaped rings)…Small Bronchi (plaques of cartilage)….
(bronchioles contain no cartilage)
What is the difference between an immune and nonimmune lung?
immune: antibodies (IgA), Macrophages, Lymphocytes, PMN recruitment and opsonization
non-immune: mucus glands, complement proteins, neutrophils
What is hemoptysis?
coughing up blood
What is dyspnea?
difficulty breathing, perception of needing to breath deeper and faster (shortness of breath)
What is atelectasis?
collapse of lung volume; inadequate expansion of air spaces
What is a pneumothorax?
air in the pleural space OR CAVITY; leads to collapse of the lung
Describe pleural effusion.
fluid within the pleural space
-it can be either transudate or exudate
What is transudate?
low protein fluid, caused by increased VENOUS pressure (CHF for example)
What is exudate?
high protein fluid, with or without inflammatory cells, caused by increased vascular PERMEABILITY (damage), pneumonia is an example
________ is suppuration in the pleural cavity; often related to bacterial infection.
Empyema
Pulmonary edema is the accumulation of ________.
Fluid in the lungs
With pulmonary edema, where does fluid accumulate first?
in the interstitial tissues…then into the distal air spaces
What are the three causes of pulmonary edema?
- increased intravascular pressure (CHF)
- hypoproteinemia (low protein)- associated with liver/kidney diseases
- vascular damage (infections, autoimmune diseases)
What is the problem with pulmonary edema?
- fluid inhibits normal oxygen exchange
- predisposes to infection (fluid become a food source for bacteria such as pneumonia)
Pulmonary thromboemboli usually originate in the _____.
deep veins of the legs or pelvis
What are the different effects of small, large, and very large emboli?
small: may only cause minimal damage
large: may causes hemorrhage or infarction
very large: may lodge at the bifurcation of pulmonary arteries and cause a saddle embolus= can causes sudden death
Name four predisposing factors to pulmonary thromboemboli.
- chronic illness
- prolonged bed rest (immobility)
- hypercoagulable state (factor V leiden)
- deep vein thrombophlebitis
There are four classes of _________ that result in airflow limitation or obstruction. What are the four?
Obstructive Pulmonary Diseases
- emphysema
- chronic bronchitis
- bronchiectasis
- asthma
True or False: Overlap among the obstructive pulmonary diseases is common.
True (emphysema + chronic bronchitis = COPD)
What is emphysema?
“alveolar wall destruction and overinflation”
- permanent enlargement of the small air spaces due to destruction of alveolar septae (alveoli start as a bunch-of-grapes but as the walls breakdown, they form one large airspace which lowers the total surface area available for gas exchange = trouble exhaling and trapping of “old air”)
- imbalance between PROTEASE and ANTI-PROTEASE enzymes
- coughing, prolonged exhalation, shortness of breath
What is the major cause of the imbalance seen in emphysema? What is the imbalance?
Major cause = smoking (breakdown of alveoli parenchyma)
-imbalance between protease and anti-protease enzymes
What are the two types of emphysema?
- centriacinar
(upper lobes effected, involves central portion of acini) - panacinar
(lower lobes usually effected, involves entire acinar unit from the respiratory bronchioles to terminal alveoli)
Panacinar emphysema is seen in patients with ______ deficiency.
alpha-1 Antitrypsin (alpha-1-AT)
Which type of emphysema is most closely related to smoking?
centriacinar (upper lobes!)
What happens: smaller “balloons/acini” of respiration no longer have elastic recoil and therefore the larger “balloons/acini” must work harder to squeeze enough air through
What are the two main clinical symptoms of chronic bronchitis?
cough AND sputum production
What causes chronic bronchitis?
chronic irritation (smoking) and infections
What are the criteria for becoming “chronic” bronchitis?
(cough + sputum) for 3 consecutive months…over 2 consecutive years
Patients with emphysema are called “______” and those with chronic bronchitis are called “______ .”
“pink puffers” -they look oxygenated
“blue bloaters” -hypoxic and cyanotic looking
What is the pathogenesis and pathology of chronic bronchitis?
pathogenesis: chronic irritation and infections (same as emphysema)
pathology: increased mucus gland layer, chronic inflammation, fibrosis and narrowing of the airways
True or False: The predisposing factors for emphysema and chronic bronchitis are the same.
True:
- cigarette smoking
- atmospheric pollutants
- infections
- genetic factors (CF, alpha-1-AT deficiency)
* although a1AT is most closely related to emphysema*
Histologically, what are two signs of chronic bronchitis?
INCREASED mucus glands (2-3 times normal)
squamous metaplasia
Narrowing of the airways occurs in ________, but dilation of the airways occurs in ________.
bronchitis (narrowing)
bronchiectasis (dilation)
True or False: Bronchiectasis is not a disease.
True, it is the RESULT of disease (permanent dilation due to fibrosis is secondary to obstruction, infection, or both)
How does bronchiectasis present clinically?
severe cough
bloody mucoid expectoration
dyspnea
fever
What are the possible implications of bronchiectasis?
abscess, pneumonia, bronchopleural fistula, and empyema
Lungs that suffer from bronchiectasis will show dilation of the distal airways. What will be grossly visible in these lungs?
fibrosis
mucus plugs
What is asthma?
increased irritability and prominence of SMOOTH MUSCLE in bronchi and bronchioles
(results in episodes of contraction and constriction)
=wheezing, long exhalation, hyperinflation of lungs
What are the common initiating factors for asthma?
allergies infection exercise drugs emotions
How common is asthma?
affects 5% of adults
affects 7 to 10% of children under 15
True or False: Asthma is more common in inner city children.
True
What are the types of asthma?
- Atopic
2. Non-atopic
______ asthma is extrinsic/allergic and is associated with Type I hypersensitivity (mediated by IgE).
Atopic
True or False: Atopic asthma commonly has a positive family history.
True
What is non-atopic asthma?
intrinsic
-initiated by viruses, or air pollutants
True or False: Either type of asthma can be triggered by emotional stress, exercise or cold temps
True
Describe the pathology of asthma.
increased mucus glands
smooth muscle hypertrophy
inflammation
What types of cells are associated with the asthma induced inflammation?
eosinophils
type 2 helper T cells
How does asthma develop (pathogenesis)?
- antigen binds to surface IgE on mast cells
- release of mediators
- mediators = histamine and leukotrienes
How is asthma treated?
- attacks may subside spontaneously
- inhalation bronchodilators can provide immediate relief (albuterol)
- control medications (corticosteroids)
The airways in asthma patients will present with thicker layers of ______ and ______.
smooth muscle
eosinophils/mucus
_______ is one of the leading causes of death (often complicates other debilitating diseases) and is caused by bacteria, virus, fungi, or parasites.
Pneumonia
What are the predisposing factors to bacterial pneumonia?
- loss of cough reflex
- injury to cilia
- immunocompromised condition
- decreased phagocytosis
- pulmonary edema (fluid = food for bacteria)
Bacterial pneumonia is associated with “productive” coughing. What does this mean?
sputum production (blood or blue-green-gunk)
What are the two major types of bacterial pneumonia?
- Bronchopneumonia = patchy, begins in small bronchi
2. Lobar pneumonia = entire lobe
Bronchopneumonia (patchy) is common in ______ or _____.
very young
very old
Lobar pneumonia occurs in healthy adults and is most commonly (90%) associated with _____ _____.
streptococcus pneumoniae
What are the stages of pneumonia?
- Congestion (increased RBC and WBC)
- Red Hepatization (purulent exudate, RBCs)
- White Hepatization (exudate with fibrin /macrophages)
- Resolution (not normal, but functioning)
If resolution and scarring does not occur, what are possible complications of bacterial pneumonia?
- abscess/empyema
- fibrinous pleuritis
- pericarditis
- bacteremia (vascularization, shock, and DIC)
Atypical (interstitial) pneumonia is caused by viruses and __________.
mycoplasma pneumoniae
How does atypical pneumonia differ clinically from bacterial pneumonia?
DRY cough***
other symptoms are variable, but include: headache, fever, myalgia
What is the pathology associated with atypical pneumonia (also called interstitial or walking pneumonia)?
INTERSTITIAL inflammation
mononuclear cells
congestion
hyaline membranes (alveolar damage is variable)
What are the “hyaline membranes” associated with interstitial pneumonia?
- thickening of interstitium that can be seen histologically as thick bands around airspaces
- also called “diffuse alveolar damage”
True or False: ARDS has the same histologic features as interstitial pneumonia.
True, acute respiratory distress syndrome shows a thickened hyaline cartilage as is seen with interstitial pneumonia
True or False: ARDS develops insidiously over the course of about 2 months.
False, very rapid…could cause death within 2-3 days
What are the causes of ARDS?
shock infection trauma drug overdose irritants aspiration fat embolism many others
ARDS presents with increased _______ ________ due to injury to the _______ and alveolar epithelium.
endothelial permeability (leaky) endothelium
Aspiration is a common predisposing factor for _____ ______.
Pulmonary Abscess
Describe the course (development) of a pulmonary abscess.
scar
cavitate
progressively enlarge
True or False: there is purulent exudate associated with pulmonary abscess.
True
How is tuberculosis spread?
inhalation
Tuberculosis infects about ____ of the world population and accounts for approximately ______ deaths per year.
1/3
3 million
most common infectious cause of death in the world
True or False: There is a higher rate of TB in immigrant and inner city populations.
True, crowing/poor living are predisposing factors
__________ tuberculosis is a bacillus, ________ that is slow-growing and ________.
Mycobacterium
aerobe
non-motile
How does M. tuberculosis resist acid destaining (making it an “acid fast bacillus”)?
its waxy coat is resistance
What is the classic tissue reaction of M.tuberculosis?
CASEATING (cheesy) granulomatous inflammation
A _____ lesion is seen at the site of early TB infection.
Ghon…. remember it’s cheesy!
What is a Ghon Complex?
parenchymal lung lesion + hilar lymph nodes
How often do primary cases of TB resolve?
90-95%
What are three possible courses for TB infections?
- inactivates (may reactivate many years later if immunity wanes)
- disseminates (involves many other organs, ex: miliary TB)
- Reactivation and induction of type IV hypersensitivity (results in tissue necrosis)
Cavitary TB is characteristic of “secondary” or “adult-type” tuberculosis and is associated with extensive ______ in the ______ of the lung.
necrosis/cavitation
apex or upper portion
How can Cavitary TB produce a tuberculosis bronchopneumonia?
- Cavities form when necrosis involves the wall of an airway
- the semi-liquid necrotic material is discharged into the bronchial tree from where it is usually coughed up
- This infected material may seed other parts of the lung via the airways to produce a tuberculous bronchopneumonia
What is Miliary TB?
- spread of TB through lymphatics or blood results in infection of other organs or systems (CNS, Kidneys, adrenals, bones, bone marrow, liver, spleen)
- looks like “millet seeds”
Granulomatous inflammation is found in processes other than TB. It is associated with _______ or fungal infections such as ______ (which is common in the Ohio River Valley)
sarcoidosis (growth of tiny collections of inflammatory cells in different parts of the body)
histoplasmosis
What is the leading cause of cancer death in the US for both men and women?
Lung Cancer
What are the risk factors for Lung Cancer?
cigarette smoking***** asbestos radon gas nickel/chromates pollutants lung scarring
Why is there such a high rate of death associated with lung cancer?
late-stage detection
True or False: Some lung tumors produce hormones.
True, or hormone-like substances (ADH, ACTH, PTH, etc.) = paraneoplastic syndromes
What is a paraneoplastic syndrome?
- a syndrome that is the consequence of cancer in the body that is not due to the local presence of cancer cells
- These phenomena are mediated by humoral factors (by hormones or cytokines) excreted by tumor cells or by an immune response against the tumor.
How does lung cancer present clinically?
cough weight loss chest pain hemotysis dyspnea
What are the two most common types of lung cancer?
Squamous Cell Carcinoma (25-30%)
Adenocarcinoma (30-35%)
True or False: There is a “small cell” and a “large cell” lung cancer.
True,
small cell (oat cell) accounts for 20-25%
large cell is less common at 10-15%
What is the prognosis for Lung Cancer?
5 year survival for all types= 16%
localize when found (however, it is hard to see it coming) = 45% survival
______ is a group of lung disorders caused by inhalation of dust or particles.
Pneumoconioses
What are important factors in pneumoconioses particles?
size
shape
concentration
What size particles are most dangerous?
1 - 5 micrometers in diameter
go figure, cigarette smoke produces particles of ~1-5 micrometers
What does pneumoconiosis do to the lungs?
inhaled particles induce fibrosis/scarring
What is a common occupation that is associated with pneumoconioses?
Coal Workers’s
- nodular or diffuse fibrosis with coal macules
- “progressive massive fibrosis” = ongoing fibrosis and lung destruction
What is the most prevalent form of occupational disease worldwide?
silicosis
_______ disorders result in reduced lung capacities. Examples include: ARDS, interstitial lung disease, and others.
Restrictive Lung
Asbestos bodies in the lungs are covered with which element?
iron
