Download ii. pyaemic lung abscesses

Bronchiectasis &
Suppurative Lung Diseases
1. Bronchiectasis.
2. Lung abscess.
3. Empyema.
1. Bronchiectasis
* Def: persistent dilatation of medium sized bronchi
accompanied by suppurative inflammation of their
walls.
* Etio-pathogenesis:
I. Weakening of the bronchial wall by;
a. Chronic suppurative inflammation: due to recurrent
septic bronchopneumonia.
b. Congenital weakness: leads to congenital
bronchiectasis.
II. Bronchial obstruction: by foreign body, bronchial
secretion or tumor.
* N/E:
- Dilated bronchi:
 Cylindrical, fusiform or saccular
 Bilateral.
 Basal.
 Has patchy distribution.
 The bronchial lumen contains pus.
 The bronchial mucosa: ulcerated.
- The surrounding alveoli are: fibrotic and
collapsed.
- The pleura shows: pleurisy
- Draining hilar L. nodes: enlarged
* Complications:
1. Spread of infection: direct, lymphatic and blood.
2. Hemoptysis.
3. Lung abscess (post-bronchiectatic lung abscess).
4. 2ry amyloidosis.
5. Lung fibrosis.
6. Bronchogenic carcinoma (squamous cell
carcinoma).
2. Lung abscess
* Definition: A localized suppurative inflammmation
due to pyogenic bacteria.
* Types:
1. inhalation (aspiration) lung abscess.
2. Pyaemic lung abscesses.
3. post-pneumonic lung abscess.
4. lung abscess complicating other conditions.
I. INHALATION (ASPIRATION) LUNG
ABSCESS
* Etiology:
• Inhalation or aspiration of septic material
from upper respiratory tract, or vomitus in
persons under general anaesthesia or in coma.
* Morphology:
• The Rt. lung is commonly affected.
• Single, related to a peripheral bronchus.
• Two forms; acute abscess & chronic abscess.
Lung abscess
Lung abscess
* Complications:
• Spread of infection: Direct, lymphatic & blood.
• Rupture leads to hemoptysis and
bronchopleural fistula.
• Lung gangrene (due to putrifaction by
saprophytic bacteria.
• Lung fibrosis leads to pulmonary hypertension.
• 2ry Amyloidosis: in chronic lung abscess.
II. PYAEMIC LUNG ABSCESSES
– Are multiple abscesses due to pulmonary pyaemia
i.e arrest of septic emboli in the pulmonary
vasculature.
* Morphologically:
•
•
•
•
Multiple.
Affect both lungs, usually peripheral (subpleural).
Related to small blood vessels.
Uniform in size & shape.
III. POST-PNEUMONIC LUNG ABSCESS
• Single or multiple abscesses complicating
pneumonia.
IV. LUNG ABSCESS COMPLICATING
OTHER CONDITIONS
• Follow Bronchiestasis.
• Secondary infected bronchogenic carcinoma.
• Infected hydatid cyst.
• Spread from subdiaphragmatic abscess.
• Penetrating chest injury.
* Clinical Course:
• The manifestations of pulmonary abscesses
are much like those of bronchiectasis and are
characterized principally by cough, fever, and
copious amounts of foul-smelling purulent or
sanguineous sputum.
• Fever, chest pain, and weight loss are
common. Clubbing of the fingers and toes may
appear within a few weeks after the onset of
an abscess.
• Diagnosis of this condition can be only
suspected from the clinical findings and must
be confirmed by chest X.ray.
• Whenever an abscess is discovered, it is
important to rule out an underlying carcinoma
because this is present in 10% to 15% of cases.
• The course of abscesses is variable. With
antimicrobial therapy, most resolve with no
major sequelae.
3. Empyema
* Definition: accumulation of purulent pleural
exudate in the pleural space due to bacterial seeding.
* Source of infection:
• Most commonly, this seeding occurs by contiguous
spread of organisms from intrapulmonary infection,
but occasionally, it occurs through lymphatic or
hematogenous dissemination from a more distant
source.
• Rarely, infections below the diaphragm, such
as the subdiaphragmatic or liver abscess, may
extend by continuity through the diaphragm
into the pleural spaces, more often on the
right side.
* Morphology:
Empyema is characterized by loculated, yellowgreen, creamy pus composed of masses of
neutrophils admixed with other leukocytes.
Although empyema may accumulate in large
volumes (up to 500 to 1000 mL), usually the
volume is small, and the pus becomes localized.
Empyema
* Course:
• Empyema may resolve, but this outcome is less
common than organization of the exudate,
with the formation of dense, tough fibrous
adhesions that frequently obliterate the pleural
space or envelop the lungs; either can seriously
embarrass pulmonary expansion.