Pneumonia
Definition
Pneumonia is an acute infection of lung parenchyma including alveolar spaces
and interstitial tissue.
• Involvement may be confined to an entire lobe -Lobar pneumonia
• A segment of a lobe-Segmental or lobular pneumonia
• Alveoli contiguous to bronchi - Bronchopneumonia
• Interstitial tissue - Interstitial pneumonia
PREDISPOSING FACTORS
Preceding respiratory viral infections • Alcoholism
• Cigarette smoking
• Underlying diseases such as Heart failure, COPD
• Age extremes
• Immunosuppressive therapy and disorders
• Decreased consciousness, comma , seizure etc
• Surgery and aspiration of secretions
The usual mechanisms to develop pneumonia are either to inhale droplets small
enough to reach the alveoli, or to aspirate secretions from the upper airways.
Other means include hematogenous dissemination, via the lymphatics, or
directly from contiguous infections
CAUSATIVE AGENT of pneumonia
Community acquired
Community-
Aspiration Pneumonia in Hospital-acquired
acquired
pneumonia: Immunocompromised pneumonia:
pneumonia
hosts:
Streptococcus occurs when Immunocompromised : a patient is said to
pneumoniae large amount of hosts such as transplant have hospital
Mycoplasma oropharyngeal or recipients, HIV infected acquired pneumonia
pneumoniae gastric contents patients, and patients if the symptoms
Pneumonia 1
, o Chlamydia are aspirated into on Chemotherapy etc. begin 48 hours after
pneumoniae the lower are prone to develop hospital admission
o Haemophilus respiratory tract. pneumonia. The and not incubating at
influenza Aspiration occurs etiologic agents are the time of
o Oral anaerobic more frequently in Common bacterial admission. Common
bacteria patients with: causes of CAP : St. organisms that cause
Staphylococcus • Decreased level Pneumoniae , hospital-acquired
aureus of consciousness H.influenzae, pneumonia are:- o
oMycobacterium (alcoholism, Mycoplasma Gram Gram-negative bacilli
tuberculosis seizure, strokes negative organisms : including
or general enterobacteriaceae Pseudomonas
anesthesia) o Funguses such as K.pneumoniaeo
• Neurologic Pneumocystis carinii, Staphylococcus
dysfunction of C.neoformans aureus ( may ne drug
oropharynx and Histoplasmosis , resistant ) o Oral
swallowing Aspergillus anaerobes.
disorders. oMycobacterium
• People with tuberculosis o Viruses :
periodontal HSV , CMV
disease are
affected more.
Common Etiologic
agents of
Aspiration
pneumonia:
It is often
polymicrobial
o Anaerobic
organisms in the
oral cavity
o Enterobateriace
o S. pneumoniae
o S.aureus
Clinical Presentation of community acquired pneumonia
1. Community acquired pneumonia can have typical or atypical presentations.
The “typical” Community acquired pneumonia: is characterized by:
1. Sudden onset with a single shaking chill. This is followed by high grade
fever
2. Cough productive of purulent, blood streaked or rusty sputum
Pneumonia 2
Definition
Pneumonia is an acute infection of lung parenchyma including alveolar spaces
and interstitial tissue.
• Involvement may be confined to an entire lobe -Lobar pneumonia
• A segment of a lobe-Segmental or lobular pneumonia
• Alveoli contiguous to bronchi - Bronchopneumonia
• Interstitial tissue - Interstitial pneumonia
PREDISPOSING FACTORS
Preceding respiratory viral infections • Alcoholism
• Cigarette smoking
• Underlying diseases such as Heart failure, COPD
• Age extremes
• Immunosuppressive therapy and disorders
• Decreased consciousness, comma , seizure etc
• Surgery and aspiration of secretions
The usual mechanisms to develop pneumonia are either to inhale droplets small
enough to reach the alveoli, or to aspirate secretions from the upper airways.
Other means include hematogenous dissemination, via the lymphatics, or
directly from contiguous infections
CAUSATIVE AGENT of pneumonia
Community acquired
Community-
Aspiration Pneumonia in Hospital-acquired
acquired
pneumonia: Immunocompromised pneumonia:
pneumonia
hosts:
Streptococcus occurs when Immunocompromised : a patient is said to
pneumoniae large amount of hosts such as transplant have hospital
Mycoplasma oropharyngeal or recipients, HIV infected acquired pneumonia
pneumoniae gastric contents patients, and patients if the symptoms
Pneumonia 1
, o Chlamydia are aspirated into on Chemotherapy etc. begin 48 hours after
pneumoniae the lower are prone to develop hospital admission
o Haemophilus respiratory tract. pneumonia. The and not incubating at
influenza Aspiration occurs etiologic agents are the time of
o Oral anaerobic more frequently in Common bacterial admission. Common
bacteria patients with: causes of CAP : St. organisms that cause
Staphylococcus • Decreased level Pneumoniae , hospital-acquired
aureus of consciousness H.influenzae, pneumonia are:- o
oMycobacterium (alcoholism, Mycoplasma Gram Gram-negative bacilli
tuberculosis seizure, strokes negative organisms : including
or general enterobacteriaceae Pseudomonas
anesthesia) o Funguses such as K.pneumoniaeo
• Neurologic Pneumocystis carinii, Staphylococcus
dysfunction of C.neoformans aureus ( may ne drug
oropharynx and Histoplasmosis , resistant ) o Oral
swallowing Aspergillus anaerobes.
disorders. oMycobacterium
• People with tuberculosis o Viruses :
periodontal HSV , CMV
disease are
affected more.
Common Etiologic
agents of
Aspiration
pneumonia:
It is often
polymicrobial
o Anaerobic
organisms in the
oral cavity
o Enterobateriace
o S. pneumoniae
o S.aureus
Clinical Presentation of community acquired pneumonia
1. Community acquired pneumonia can have typical or atypical presentations.
The “typical” Community acquired pneumonia: is characterized by:
1. Sudden onset with a single shaking chill. This is followed by high grade
fever
2. Cough productive of purulent, blood streaked or rusty sputum
Pneumonia 2
