Emphysema is a lung disease characterized by abnormal enlargement of the air spaces in the lungs. There are several types of emphysema including centriacinar, panacinar, distal acinar, and irregular emphysema. The main pathogenesis involves an imbalance between protease enzymes like elastase released by smoke exposure and antioxidant proteins like alpha-1 antitrypsin that normally inhibit these enzymes. This imbalance leads to destruction of lung elastic tissue and enlargement of the air spaces. Patients may present as "pink puffers" with barrel chests and prolonged expiration or "blue bloaters" with hypoxia and cor pulmonale. Diagnosis involves spirometry showing reduced FEV1 and imaging

1. Emphysema
Presented By:
Aamir Sharif
M.Phil Human Pathology & Microbiology
SMC

2. Definition
• Emphysema is abnormal permanent
enlargement of air spaces distal to terminal
bronchioles accompanied by destruction of
their walls without obvious fibrosis
• Emphysema may be pure but in majority of
cases it is accompanied by chronic bronchitis

3. Types
Centriacinar emphysema
• The central parts of acini
formed by respiratory
bronchioles are affected
• Most common in upper
lobes in smokers
Panacinar emphysema
• Acini are uniformly enlarged
from resp . Bronchiole to
alveoli
• Tend to occur more commonly
in lower lung lobes in @1-
antitrypsin deficiency.

4. Types Cont..
Distal acinar emphysema
(paraseptal)
• The proximal portion of the
acinus is normal but distal part
is involoved.
• Localized along the pleura,
adjacent to perilobular septa
• More severe in upper half of
lung
• Bullae formation (multiple,
contigous, enlarged airspaces
<0.5 mm>2.0 cm cyst like
structure)
irregular emphysema
• Acinus is irregularly
involved.
• Associated with scarring
• Resulting from healed
inflammatory disaese.
• Often asymptomatic

5. PATHOGENESIS
PROTEASE -ANTI PROTEASE
IMBALANCE
• In serum proteinase inhibitors are present
esp. antielastase (alpha 1 antitrypsin encoded
by genes chr. 14.) which prevent the
destruction of elastic tissue by the enzyme
elastase
• This hypothesis is based on observation that
more than 80% of individuals with @1
antitrypsin deficiency develop emphysema.

6. Cont..
• In smokers , macrophages and
neutrophils accumulate in alveoli
which are rich in elastases.
• Nicotine and reactive oxygen
species in smoke deplete
antioxidants and activate IL-8,
LTB4, TNF
• Activated granules release
 Elastase
 Proteinase 3
 Cathepsin G
• Smoking also inhibit alpha 1
antitrypsin & thus decreases net
antielastase activity in smokers.

7. GROSS
MORPHOLOGY
• Panacinar emphysema
when well developed
produces Pale voluminous
lungs
• The lungs are Deeper pink,
less voluminous
• Upper two thirds of lungs
are more severely affected
Panacinar

8. MORPHOLOGY
• Histologically, there is thinning and destruction of
alveolar walls.
• With advanced disease adjacent alveoli become
confluent, creating large airspaces.
• Terminal and respiratory bronchioles may be
deformed bc of loss of septa.
• Small airways tend to collapse during expiration
due to loss of elastic tissue in septa which reduces
radial traction on the small airways.(an important
cause of chronic airflow obstruction in severe
emphysema)

9. CLASSIC PRESENTATION
• Individuals who have no bronchitic component
are barrel shaped chest and dyspnea , with
prolonged expiration.
• Patient over ventilate & remain well oxygenated,
called Pink Puffer
• Characteristic posture…sitting forward in
hunched over position attempting to
squeeze air out of lungs with each expiratory
effort.

10. • Patients WITH BRONCHITIC COMPONENT
have less prominent dyspnea and respiratory
drive ,so they become hypoxic , retain
CO2,and are often cynotic.
• Often they seek help after onset of
cor pulmonale and associated edema.
Patients with this clinical picture are called
BLUE BLOATERS.

11. Diagnosis
Spirometry
Reduced FEV1 with normal or
near normal FVC
CXR shows
1. A chest X-ray demonstrating
severe COPD. Note the small size
of the heart in comparison to
the lungs.
2. A lateral CXR of a person with
emphysema. Note the barrel
chest and flat diaphragm
3. Lung bulla as seen on CXR in a
person with severe COPD
associated with anti 1
antitrypsin deficiency
4. Bullous emphysema
5. Bullus emphysema as seem on
CT

12. A chest X-ray demonstrating severe COPD. Note the
small size of the heart in comparison to the lungs.

13. A lateral CXR of a person with emphysema. Note the
barrel chest and flat diaphragm

14. Lung bulla as seen on CXR in a person with severe
COPD associated with anti 1 antitrypsin deficiency

15. Bullous emphysema

16. Bullus emphysema as seem on CT