pneumonia

Question 1

PNEUMONIA definition

Answer 1

infection of the lung parenchyma
• Due to infection affecting distal airways and alveoli, with
the formation of an inflammatory exudate.
• Caused by a wide variety of infective pathogens

Question 2

Bronchopneumonia

Answer 2

There is patchy
consolidation involving the
lung

Question 3

Lobar pneumonia

Answer 3

Whole lobe of the lung is

affected

Question 4

Bronchopneumonia PREDISPOSING CONDITIONS

Answer 4

• Extremes of age: infants and elderly
• Debilitating diseases: cardiac failure, chronic renal failure, CVA
• Pre-existing lung conditions: acute bronchitis, chronic obstructive
airway disease , cystic fibrosis.
• Failure to clear respiratory secretions: post-operative.
• Manifestation 2º to viral infection: influenza, measles

Question 5

bronchopneumonia AETIOLOGICAL AGENTS

Answer 5

Streptococcus pneumoniae
• Klebsiella pneumoniae
• Staphylococcus aureus
• Streptococcus pyogenes
• Haemophilus influenzae
• Pseudomonas aeruginosa
• Legionella pneumophila

Question 6

bronchopneumonia CLINICAL FEATURES

Answer 6

Fever
• Reduced consciousness
• Crackles (crepitations) on auscultation
• Septicaemia

Question 7

bronchopneumonia PATHOGENESIS

Answer 7

Organisms colonise the
bronchioles to cause
bronchiolitis.
• Inflammation spreads
through the wall of a
bronchiole into surrounding
alveoli.
• There may be significant
damage to bronchiolar
walls

Question 8

bronchopneumonia GROSS MORPHOLOGY

Answer 8

Patchy consolidation
• Basal and bilateral
lesions
• Initially focal, involving
one or more lobes
• Post mortem findings:
• grey or grey-red lung
• little resistance when
gently pressing on
affected area

Question 9

bronchopneumonia MICROSCOPIC FEATURES

Answer 9

Neutrophil-rich exudate that
fills the bronchi,
bronchioles, and adjacent
alveolar spaces.
• Ciliated epithelium of
bronchioles is damaged.
• Capillaries are congested

Question 10

LOBAR PNEUMONIA PREDISPOSING CONDITIONS

Answer 10

Adults ages 20-50
• Male predominance
• Elderly, diabetics, alcoholics

Question 11

LOBAR PNEUMONIA AETIOLOGICAL AGENTS

Answer 11

Streptococcus pneumoniae infection common

• Klebsiella pnumoniae

Question 12

LOBAR PNEUMONIA CLINICAL FEATURES

Answer 12

• -Acute onset
• -Fever, rigors
• -Dry cough
• -Rusty sputum
• -Pleuritic chest pain

Question 13

LOBAR PNEUMONIA PATHOGENESIS

Answer 13

Organism inhaled into bronchial tree and reaches alveoli.
• Bacteria cause an inflammatory exudate which is initially watery.
Later, there is exudation of fibrin and neutrophils in the alveoli.
• Alveoli filled with exudate = consolidation.
• Exudate flows directly into the next alveolus via pores of Kohn,
carrying bacteria with it. Infection spread is through lumen rather
than through walls. This is important in that the damage to
bronchioles is much less than in bronchopneumonia

Question 14

Four stages of lobar pneumonia

Answer 14

1. Congestion
2. Red hepatization
3. Grey hepatization
4. Resolution

Question 15

COMPLICATIONS OF PNEUMONIA

Answer 15

1. Healing with fibrosis leading to bronchiectasis
2. Lung Abscess
3. Empyema
4. Spread of inflammation

Question 16

Community-acquired Atypical

Pneumonias

Answer 16

characterized by patchy inflammatory
changes in the lungs, largely confined to the alveolar septa and
pulmonary interstitium

Question 17

Community-acquired Atypical Pneumonias examples

Answer 17

Mycoplasma pneumoniae
• Particularly common among children and young adults.
• Occur sporadically or as local epidemics in closed communities
(schools, military camps, prisons).
Chlamydia pneumoniae
• Milder pneumonia
• Relatively common in asthmatics
Legionella pneumophila
• Causes severe pneumonia
• Legionnaires’ disease

Question 18

Viral pneumonia

Answer 18

• Influenza
• Human metapneumovirus
• Coronavirus

Question 19

Influenza

Answer 19

Single-stranded RNA virus, bound by a
nucleoprotein that determines the virus type (A,
B, or C)

Question 20

Human metapneumovirus

Answer 20

Paramyxovirus
• Common in young, elderly, immunocompromised
• Can develop severe infection

Question 21

NOSOCOMIAL INFECTIONS

Answer 21

known as hospital-acquired, pneumonias are defined
as pulmonary infections acquired in the course of a hospital
stay.

Question 22

ASPIRATION PNEUMONIA

Answer 22

Aspiration pneumonia occurs in debilitated patients or those who aspirate
gastric contents either while unconscious (e.g. after a stroke) or during
repeated vomiting.
Abscess formation is a common complication.

Question 23

LUNG ABSCESS

Answer 23

A localized area of
suppurative necrosis within
the pulmonary
parenchyma, resulting in
the formation of one or
more large cavities.
• More common on right side
following aspiration
• More common basally and
bilaterally in pneumonia

Question 24

The causative organism may be introduced into the lung by any of the following
mechanism

Answer 24

• Aspiration of infective material
• Antecedent primary lung infection
• Septic embolism.
• Neoplasia.
• Miscellaneous.

Question 25

CHRONIC PNEUMONIA

Histoplasmosis capsulatum

Answer 25

Warm, moist soil contaminated
by droppings from bats and
birds containing fungal spores
• More common in
immunocompromised
• Cause granulomatous
inflammation in lung
• Yeast forms: round to oval, 2 to
4 μm in diameter.

Question 26

Blastomyces dermatitidis

• Three clinical forms:

Answer 26

• Pulmonary blastomycosis
• Disseminated blastomycosis
• Rare primary cutaneous form
(from direct inoculation of
organisms into the skin)

Question 27

Common bacterial

pathogens

Answer 27

 S. pneumonia
 H. influenza
 S. aureus
 M. tuberculosis

Question 28

Fungi

Answer 28

• Pneumocystis jirovecii
• C. neoformans
• H. capsulatum
• C. immitis
• Aspergillus spp.

Question 29

Protozoa

Answer 29

• T. gondii
• Cryptosporidium
• Strongyloides stercoralis

Question 30

Viruses

Answer 30

Cytomegalovirus

Question 31

Mucormycosis

Answer 31

Caused by Rhizopus and Mucor

fungi of the Zygomycetes class