Id 1Y1: Bacterial Pneumonia

Front 1

Common cause of pneumonitis

Back 1

acid aspiration; vasculitis; auto-immune process;

i.e. (includes NON-infectious processes)

Front 2

Normal respiratory flora (commensals)
that can cause pneumonia

Oropharynx: name organisms

Back 2

streptococci, anaerobes

Front 3

Normal respiratory flora (commensals)
that can cause pneumonia

Nasopharynx: name organisms

Back 3

streptococci, staphylococci, non-typeable haemophilus, moraxella species

Front 4

Normal respiratory flora (commensals)
that can cause pneumonia

Bronchopulmonary tree: name organisms

Back 4

sterile below the carina

Front 5

Exogenous pathogens present only transiently in respiratory tract that can cause pneumonia:

Back 5

Respiratory viruses, Streptococcus pneumoniae, Haemophilus influenzae (type b & others), Neisseria meningitidis, Streptococcus pyogenes, others

Front 6

Exogenous pathogens usually gain access to respiratory tract via ________________ or _______________

Back 6

droplet transmission (cough/sneeze)

or

contiguous spread (unwashed hands to face after touching items contaminated with respiratory secretions)

Front 7

What reflex prevents large particulate matter from reaching central airways?

Back 7

Epiglottic reflex

Front 8

What reflex causes material that reaches trachea or major bronchi to be expelled?

Back 8

Cough reflex

Front 9

What encourages turbulence and particle deposition on mucosal surfaces?

Back 9

Sharp angles of central airways

Front 10

Mucociliary escalator:
- covers which portion of respiratory tract?
- mucus contains which antimicrobial compounds?

Back 10

Cilia present on cells from nose to terminal bronchioles

Moves mucous up towards larynx where expelled

Mucus contains antimicrobial compounds (lactoferrin, lysozyme, secretory IgA)

Front 11

Host Defense: Alveoli

Alveolar lining fluid contains substances which are opsonins or are directly microbicidal:

Name them

Back 11

surfactant,
fibronectin,
immunoglobulin,
complement,
free fatty acid,
iron-binding proteins

Front 12

Host Defense: Alveoli

4 macrophage populations for phagocytosis, antigen processing, cytokine release:

Back 12

Alveolar macrophages – primary phagocyte

Interstitial macrophages

Dendritic cells

Intravascular macrophages

Front 13

T/F
1) No mucociliary defenses in the alveoli

T/F
2) T- and B-lymphocytes are not present in submucosa and nearby BALT

Back 13

1) True

2) False

Front 14

Host Defense: Immune Response
Non-immune lung:
- opsonization by?
- phagocytosis by?

Back 14

opsonization by complement from capillaries

phagocytosis by PMNs from capillaries or alveolar macs

Front 15

Host Defense: Immune Response
Immune lung:
- opsonization by?
- phagocytosis by?

Back 15

opsonization by IgA from plasma cells lining the respiratory epithelium or by IgG from capillaries

phagocytosis by PMNs from capillaries or alveolar macs

Front 16

Risk Factors for Pneumonia

Name 4 categories

Back 16

Disruption of mechanical/anatomical barriers

Inc. exposure to pathogens

Immune Deficiency

Iatrogenic manipulations

Front 17

Risk Factors for Pneumonia

1. Disruption of anatomical or mechanical barriers (cilia dysfunction, altered secretions, airway obstruction)

Give examples

Back 17

- Smoking (most common)
- Congestive heart failure
- COPD/asthma

Front 18

Risk Factors for Pneumonia

2. Increased exposure to pathogens

Give examples

Back 18

Crowding (jail, housing, day care, winter months)

Aspiration (in hospital, post-CVA, alcoholism, seizure disorder)

Front 19

Risk Factors for Pneumonia

3. Immune deficiencies

Give examples

Back 19

Lack of breastfeeding (infants)
Age – very young and elderly
Diabetes
HIV

Front 20

Risk Factors for Pneumonia

4. Iatrogenic manipulations - bypass host defenses

Give examples

Back 20

Bronchoscopy (even with most advanced hygiene control)

Sedation

Medical immunosuppression

Front 21

Pneumonia: Clinical presentation - symptoms:

Name "classic" acute CAP symptoms:

Name "other" less specific symptoms:

Back 21

Classic acute CAP:
Fever + SOB
Productive cough (80%)
Pleuritic chest pain (30-46%)

Other symptoms:
Fatigue (91%)
Anorexia (71%)
Sweats (69%)
Chills (40-70%)

Front 22

Pneumonia: Clinical presentation - signs

Name the signs:

Back 22

Fever (68-78%)
Tachypnea (45-69%)
Rales (78%) – (crackles) common;
Bronchial breath sounds suggesting consolidation (29%)
Leukocytosis with left shift

Front 23

Pneumonia: Clinical presentation - signs

What do you need to consider when taking a CXR of a patient with possible pneumonia?

Back 23

Infiltrate on CXR may be absent in the presence of volume deficit; high false negative rates for dry/volume depleted patients

Front 24

Clinical presentation:

Pneumonia in the elderly?

Back 24

non-specific complaints, delirium, dyspnea

Front 25

Clinical presentation:

Aspiration pneumonia?

Back 25

poor dentition,
history of loss of consciousness or poor airway control,
occurs in dependent lobes,
may be sudden onset after a meal,
often polymicrobial with anaerobes

Front 26

Clinical presentation:

Atypical pneumonia (chlamydia, mycoplasma, legionella)?

Back 26

“walking pneumonia”,
may have more gradual onset,
less sputum production,
more often diffuse infiltrates

Front 27

Clinical presentation:

Post-obstructive pneumonia?

Back 27

occurs distal to a bronchial obstruction (usually cancer),
more likely to be gram negative,
anaerobic and polymicrobial,
often recurrent unless obstruction is relieved

Front 28

Streptococcus pneumoniae

Predominant etiologic agent of children or adult CAP?

Gram _____ ?

Colonizes the ______of 5-10% of adults and 20-40% of children

What factors increase mortality?

Back 28

Predominant etiologic agent of adult CAP

Gram positive diplococcus

Colonizes the nasopharynx of 5-10% of adults and 20-40% of children

High mortality (15% overall; 30% in chronically ill patients)

Mortality increased with increased number of lobes involved, age, and associated comorbidities.

Front 29

Streptococcus pneumoniae

Virulence factors?

How does it cause most of its damage?

Back 29

Virulence factors
- Polysaccharide capsule (protects from opsonization & phagocytosis)

Produces few toxins; most of its damage is done by eliciting an intense inflammatory response

Front 30

Haemophilus influenzae pneumonia

Majority of isolates are type ___?

What disease is H. influenza pneumonia commonly associated with?

T/F
Resistance is common across all classes of beta-lactam

Back 30

Majority of isolates are either type b or unencapsulated

Associated with chronic lung disease (COPD)

F

Resistance is common through a beta-lactamase mechanism, creating resistance to penicillin, ampicillin, and 1st generation cephalosporins, but SUSCEPTIBLE to higher-level beta-lactams

Front 31

Moraxella (Branhamella) catarrhalis

What organism is this commonly confused with on gram stain?

Where does it commonly colonize?

To where is the infection known to spread?

T/F
Resistance is rising across all classes of beta-lactam

Back 31

Indistinguishable from Neisseria on gram stain

Colonization of nasopharyngeal mucosa; 66% of infants are colonized; 1-5% of adults are colonized

Contiguous spread to middle ear, sinuses or lower tract

F

Like H. influenzae, resistance by a beta-lactamase, making them resistant to penicillin, ampicillin, and 1st generation cephalosporins, but SUSCEPTIBLE to higher-level beta-lactams

Front 32

Staphylococcus aureus

What other infections is staph. aureus pneumonia commonly associated with?

T/F
In otherwise healthy children and adolescents, it is associated with a mild pneumonia

What toxin is associated with cavitation and tissue necrosis?

T/F
Pleural effusion and empyema are common

Initial treatment of choice?

Back 32

Associated with high rates of skin and soft tissue infection

False
Associated with severe, necrotizing pneumonia in otherwise healthy children and adolescents

PVL toxin (Panton-Valentin Leukocidin) is associated with cavitation and tissue necrosis

True
Pleural effusion and empyema are common

Initial treatment = vancomycin

Front 33

Atypical organisms

What 3 organisms are associated with atypical presentations of CAP?

What would a chest radiograph show?

Clinical presentation?

Treatments?

Back 33

Legionella pneumophila, Chlamydia pneumoniae, and Mycoplasma pneumoniae are the 3 organisms Associated with atypical presentations of CAP

Chest radiographs may show a diffuse interstitial infiltrate

Clinical presentation may be more indolent, with dry cough

Generally treatable with macrolide, fluoroquinolone, or doxycycline

Front 34

Which of the atypicals is associated with severe pneumonia with extrapulmonary manifestations?

Back 34

Legionella may be associated with more severe pneumonia with extrapulmonary manifestations

Front 35

Pleural effusion and empyema

T/F
Most are small, uncomplicated, and resolve without drainage.

Back 35

Most are small, uncomplicated, and resolve without drainage.

Front 36

Pleural effusion and empyema

What are indications for evaluating with thoracentesis?

Back 36

If its thickness is >1cm on a lateral decubitus film,
or

For persistent, unexplained fever

Front 37

Pleural effusion and empyema

How are they commonly evaluated if their thickness is >1cm on a lateral decubitus film or for persistent, unexplained fever?

Back 37

Thoracentesis

Front 38

Empyema

Definition?

What must you do if empyema is found?

What should be considered when pleural fluid pH is <7.0, glucose is <40, or gram stain is positive.

Back 38

The presence of pus in the pleural space.

Empyema must undergo chest tube drainage.

Chest tube drainage should also be considered when pleural fluid pH is <7.0, glucose is <40, or gram stain is positive.

Front 39

CAP Diagnosis

History?

Physical?

Back 39

History
Evaluate for risk factors

Physical examination
Include oxygen saturation by pulse oximetry

Front 40

CAP Diagnosis

Lab Data?

Back 40

Laboratory data:
- Blood and sputum culture
- HIV testing for patients age 15-54yo
- CBC

If hospitalized:
- Other blood chemistries
- Arterial blood gases in patients with more severe respiratory compromise
- Testing for etiology

Radiographic data
- Chest Radiograph, including decubitus film if effusion is present

Front 41

Testing for Etiologic Agents of Pneumonia

When do you test for blood cultures?

Back 41

Before antibiotics

At onset of illness; repeat if persistent fever

Yield: 15% among hospitalized patients

Front 42

Testing for Etiologic Agents of Pneumonia

Expectorated sputum (gram stain + culture)
- when do you test sputum?

Back 42

Before antibiotics for best yield

Front 43

You should only check induced sputum when you suspect what 2 organisms?

For what 2 reasons would you order a fiberoptic bronchoscopy?

Back 43

M. tuberculosis and P. carinii

1) For detection of anatomic lesions in suspected postobstructive pneumonia

2) For deep culture +/- biopsies for non-resolving pneumonia or when unusual pathogens are suspected

Front 44

Testing for Etiologic Agents of Pneumonia II

This test is acceptable adjunct; it can make diagnosis faster than culture in most cases; Sensitivity about 75%, specificity about 90%

It can make diagnosis even when cultures negative (i.e. when antibiotics started prior to cultures)

What test is this?

Back 44

S pneumoniae urinary antigen

Front 45

CAP Treatment:

What 2 major categories of treatment are often used?

Back 45

Supportive (BP support / Ventilator)
Antibiotics (Empiric, Pathogen-directed)

Front 46

Empiric adult CAP treatment: preferred antibiotics

Outpatient ?

General medical ward ?

Intensive care unit ?

Back 46

Outpatient:
- macrolide
- fluoroquinolone with enhanced activity against S. pneumo (e.g. levo/ moxi/gatifloxacin)
- doxycycline

General medical ward:
- (ceftriaxone or cefotaxime) plus macrolide
- (amp-sulbactam or pip-tazo) plus macrolide
- enhanced fluoroquinolone

Intensive care unit
- (ceftriaxone or cefotaxime or amp-sulbactam or pip-tazo) plus (macrolide or enhanced fluoroquinolone)

Front 47

Prevention of CAP

4 strategies?
Which is most important?

Back 47

Hand hygiene (VERY important)

Active Immunization (Hib for H. influ b, Prevnar, Pneumovax -adults, Influenza - adults+peds)

Passive Immunization – breast milk

Avoid exposures that thwart defense mechanisms of the respiratory tract (tobacco smoke, crowding, etc.)

Front 48

Hospital-acquired pneumonia

Onset?

Factors which compromise defenses? (name 6)

Which class of bacteria predominate?

Back 48

Onset 48-72hrs after admission

Factors which compromise host defenses:
- Altered mental status
- Poor nutritional status
- Decreased clearance of secretions
- Respiratory tract obstruction
- Diminished lung expansion
- Endotracheal intubation, bypassing host defenses

Altered host commensal flora, with gram-negative predominance

Increased presence of drug-resistant bacteria

Mortality 20-70%

Front 49

Hospital Acquired Pneumonia

Which organism is of interest because of its rise in resistance?

Back 49

Acinetobacter

Front 50

HAP Prevention

What are some prevention strategies?

Back 50

- Hand washing / careful cleaning of equipment

- Aspiration precautions
- Avoidance of unnecessary sedation
- Head of bed elevation in high-risk patients

- Aggressive healthcare worker influenza vaccination

- Avoidance of unnecessary gastric acid blockade