? 1.Chronic bronchitis
? 2.Pneumonia
? 3.Pneumoconiosis
? 4.Carcinoma of the respiratory
? Chronic bronchitis and emphysema (COPD)
almost always co-exist to some degree.
Together they rank fifth in the global
burden of disease; in the UK COPD affects
approximately 6% of men and 4% of
women over the age of 45.
? Chronic bronchitis is a clinical term
defined as chronic cough and sputum
for at least 3 months each year for 2
consecutive years.
?Emphysema is an anatomical term
defined as permanent
enlargement of airspaces distal to
the terminal bronchioles,together
with destruction of their walls.
Chronic bronchitis
? 1,Chronic bronchitis
? 2,Pulmonary emphysema
? 3,Cor pulmonale
? 4,Bronchiectasis
一,Chronic bronchitis
Aetiology
? 1,Cigarette smoking.
? 2,Air pollution
? 3,Low-grade bronchial infections
The earliest abnormality in chronic
bronchitis is thought to be a
respiratory bronchiolitis,affecting
airways of less than 2 mm in
diameter.
squamous metaplasia
? Bronchial abnormalities are
mainly mucus hypersecretion
with chronic inflammation;
these features produce the
typical cough and sputum.
? 1 Mucus hypersecretion with
chronic inflammation; these
features produce the typical cough
and sputum.
? 2 The metaplastic squamous
epithelium may become dysplastic
from persistent injury by smoking.
? Suffice to say
that all forms
of pulmonaty
emphysema
show
destruction
of distal lung
parenchyma.
This is normal lung microscopically,The alveolar walls
are thin and delicate,The alveoli are well-aerated and
contain only an occasional pulmonary macrophage (type
II pneumonocyte).
Microscopically at high magnification,the loss of alveolar
walls with emphysema is demonstrated,Remaining
airspaces are dilated.
The chest cavity is
opened at autopsy to
reveal numerous large
bullae apparent on the
surface of the lungs in
a patient dying with
emphysema.Bullae are
large dilated airspaces
that bulge out from
beneath the
pleura.Emphysema is
characterized by a loss
of lung parenchyma by
destruction of alveoli
so that there is
permanent dilation of
airspaces.
Pulmonary
emphysema
? Centrilobular (centriacinar) emphysema
involves airspaces in the center of lobules.
? Paraseptal (distal acinar) emphysema
involves airspaces at the periphery of the
lobules
? Interstitial emphysema is most commonly
due to traumatic rupture of an airway or
spontaneous rupture of an
emphysematous bulla.
Pulmonary emphysema
Pulmonary emphysema
bullae lung
? The cause of
the
bronchiectasis
is nearly always
severe distal
inflammation
leading to lung
fibrosis,then
dilatation of
airways and
damage to their
walls.
Cor Pulmonale
3,Pneumonia
Pneumonia is usually due to
infection affecting distal
airways,especially alveoli,
with the formation of an
inflammatory exudate.
Pneumonia may be classified
according to several criteria.
? The two anatomical patterns,
lobar and bronchopneumonia,
can result from infection by one
of several types of bacteria,
some of which have been
mentioned above.There are also
several other pathogens that
cause distinct types of
pneumonia.
Lobar pneumonia
? pneumonia typically affects
otherwise healthy adults
between 20 and 50 years of
age; however,lobar pneumonia
caused by klebsiella typically
affects the elderly,diabetics or
alcoholics,Symptoms include a
cough,fever and production of
sputum.
? The sputum appears purulent
and may contain flecks of
blood,socaIIed ‘rusty' sputum.
Fever can be very high (over
4O℃ ),with rigors,Acute
pleuritic chest pain on deep
inspiration reflects
involvement of the pleura.
? As the lung becomes
consolidated,the chest
signs are dullness to
percussion with increased
whispering pectoriloquy,
and bronchial breathing.
The dullness recedes with
resolution of the exudate.
The pathology of lobar pneumonia is a
classic example of acute inflammation,
Involving four stages:
? A,Congestion
? B,Red hepatisation.
? C,Grey hepatisation.
? D,Resolution.
① A,Congestion.
? This first stage lasts for about
24 hours and represents the
outpouring of a protein-rich
exudate into alveolar spaces,
with venous congestion,The
lung is heavy,oedematous and
red.
② B,Red hepatisation.
? In this second staged which lasts for
a few days,there is massive
accumulation in the alveolar spaces
of polymorphs,together with some
lymphocytes and macrophages,Many
red Cells are also extravasated from
the distended capillaries,The
overlying pleura bears a fibrinous
exudate,The lung is red,solid and
airless,with a consistency
resembling fresh liver.
Red hepatisation.
Grey hepatisation,The lung is now grey-brown and solid,A
closer view of the lobar pneumonia demonstrates the distinct
difference between the upper lobe and the consolidated lower
lobe,Radiographically,areas of consolidation appear as
infiltrates.
?This third stage also lasts a few days and
represents further accumulation of fibrin,with
destruction of white cells and red cells.
D,Resolution,
? This fourth stage occurs at about 8-
10 days in untreated cases,and
represents the resorption of exudate
and enzymatic digestion of
inflammatory debris,with
preservation of the underlying
alveolar wall architecture,Most
cases of acute lobar pneumonia
resolve in this way.
This is a lobar
pneumonia in which
consolidation of the
entire left upper lobe
has occurred,
1.Bronchopneumonia
? Bronchopneumonia has a
characteristic patchy distribution,
centred on inflamed bronchioles and
bronchi with subsequent spread to
surrounding alveoli,It occurs most
commonly in old age,in infancy and in
patients with debilitating diseases,such
as cancer,cardiac failure,chronic renal
failure or cerebrovascular accidents.
lobular pneumonia
The inflamed lung parenchyma can be
demonstrated by gently pressing on an affected
area;normal lung recoils like a sponge,whilst
pneumonic lung offers little resistance.
The cut surface of this
lung demonstrates the
typical appearance of a
bronchopneumonia with
areas of tan-yellow
consolidation,
Remaining lung is dark
red because of marked
pulmonary congestion,
Bronchopneumonia
(lobular pneumonia) is
characterized by patchy
areas of pulmonary
consolidation,
Bronchopneumonia may also occur in
patients with,
? 1.acute bronchitis,
? 2.chronic obstructive airways disease or
cystic fibrosis.
? 3.Failure to clear respiratory secretions,
such as is common in the post-operative
period,also predisposes to the
development of bronchopneumonia.
This radiograph
demonstrates patchy
infiltrates consistent
with a
bronchopneumonia from
a bacterial infection,
Typical organisms
include Streptococcus
pneumoniae,
Staphylococcus aureus,
Pseudomonas aeruginosa,
Hemophilus influenzae,
Klebsiella pneumoniae,
among others.
Another example of a
bronchopneumonia,
The lighter areas that
appear to be raised
on cut surface from
the surrounding lung
are the areas of
consolidation of the
lung.
? the pattern of patchy
distribution of a
bronchopneumonia is
seen,The consolidated
areas here very closely
match the pattern of
lung lobules (hence the
term "lobular"
pneumonia).
? A bronchopneumonia is
classically a "hospital
acquired" pneumonia
seen in persons already
ill from another disease
process,Typical
bacterial organisms
include,Staphylococcus
aureus,Klebsiella,E.
coli,Pseudomonas.
At the left the alveoli are filled with a neutrophilic exudate that
corresponds to the areas of consolidation seen grossly with the
bronchopneumonia,This contrasts with the aerated lung on the
right of this photomicrograph.
Seen here are two lung
abscesses,one in the upper
lobe and one in the lower
lobe of this left lung,An
abscess is a complication of
severe pneumonia,most
typically from virulent
organisms such as S,
aureus,Abscesses are
complications of aspiration,
where they appear more
frequently in the right
posterior lung.
? Affected areas of the lung tend to be
basal and bilateral,and appear
focally grey or grey-red at
postmortem, Histology shows
typical acute inflammation with
exudation,With antibiotics and
physiotherapy,the areas of
inflammation may resolve,or heal by
organisation with scarring.
Pneumoconiosis
? Silicates are inorganic minerals
abundant in stone and sand.
? Any industrial worker involved
in the grinding of stone or sand
will be at risk from silicosis.
? The lungs show
scattered minute
nodules of
hard,fibrous
tissue with
surrounding
irregular
emphysema.Adva
nced cases show
the typical
features of end-
stage diffuse
pulmonary
fibrosis,togather
with numerous
silicotic nodules.
Syndrome
?1.Tuberculosis of the lung
? 2,Cor pulmonale
4,Carcinoma of the
respiratory
?A,Nasopharyngeal carcinoma
?B,Carcinoma of the Lung
Nasopharyngeal carcinoma
Histological classification
? ① Squamous cell carcinoma.
? ② Adenocarcinomas
? ③ undifferentiated carcinomas
Squamous cell carcinoma.
Squamous cell carcinoma.
Squamous cell carcinoma.
㈡ Carcinoma of the Lung
Aetiology
Maior ask factors for the development of
lung cancer are,
? cigarette smoking;
? occupational h~s,e.g,inhalahon of
asbestos and other dusts,radioactive
gsses;
? pulmonary fibrosis.
2.Clinical features
? Weight loss,cough and haemoptysis are
common presenting features,Weight
loss is often severe and may be due to
humoral factors from the tumour.
? Dyspnoea and chest pain are also
common;the latter is often pleuritic and
due to obstructive changes.
This is a squamous cell
carcinoma of the lung
that is arising centrally
in the lung (as most
squamous cell
carcinomas do),It is
obstructing the right
main bronchus,The
neoplasm is very firm
and has a pale white
to tan cut surface.
Arising centrally in
this lung and
spreading extensively
is a small cell
anaplastic (oat cell)
carcinoma,The cut
surface of this tumor
has a soft,lobulated,
white to tan
appearance,The tumor
seen here has caused
obstruction of the
main bronchus to left
lung so that the
distal lung is
collapsed,
This is a peripheral adenocarcinoma of the lung.
There are four major types of lung
cancer,classified according to their
appearance on light microscopy; their
approximate incidences are:
? squamous cell carcinoma (SqCC),20-
30%
? small cell lung carcinoma (SCLC)
(including oat cell carcinoma) and
bronchial carcinoids,15-20%
? adenocarcinoma (AC),30-40%
? large cell undifferentiated carcinoma
(LCUC):10-15%.
Squamous cell carcinoma.
the bronchioloalveolar carcinoma is composed of columnar cells
that proliferate along the framework of alveolar septae,The cells
are well-differentiated,These neoplasms in general have a better
prognosis than most other primary lung cancers,
This is the microscopic pattern of a small cell anaplastic (oat cell)
carcinoma in which small dark blue cells with minimal cytoplasm
are packed together in sheets.
? Patients may present with,or ultimately
develop,metastases; common sites
include lymph nodes,
? bone,
? brain,
? liver
? adrenals.
Here is an oat cell
carcinoma which is
spreading along the bronchi,
The speckled black rounded
areas represent hilar lymph
nodes with metastatic
carcinoma,These
neoplasms are more
amenable to chemotherapy
than radiation therapy or
surgery,but the prognosis
is still poor,Oat cell
carcinomas occur almost
exclusively in smokers.
?
? Paraneoplastic effects are common and
are due to ectopic hormones:ACTH and
ADH from small cell lung carcinomas,PTH
from squamous cell carcinomas,Finger-
clubbing and hypertrophic pulmonary
osteoarthropathy are common.
This pattern is much less common than the
bronchopneumonia pattern,In part,this is due to
the fact that most lobar pneumonias are due to
Streptococcus pneumoniae (pneumococcus) and
for decades,these have responded well to
penicillin therapy so that advanced,severe cases
are not seen as frequently,However,
pneumoccoci,like most other bacteria,are
developing more resistance to antibiotics,Severe
pneumococcal pneumonia still occurs,even in
young to middle aged persons (not just the very
young and the very old) and has a mortality rate
of 20%!