Lower Respiratory Tract Infections

Question 1

MC infections involving the lower respiratory tract

Answer 1

bronchitis
bronchiolitis
pneumonia

Question 2

Bronchitis

Answer 2

inflammation of the walls of the bronchi and bronchioles –> narrowing

effects large elements of tracheobronchial tree

acute: all ages
chronic: adults

Question 3

Bronchiectasis

Answer 3

widening of bronchi and bronchioles

excessive mucus production narrows bronchial tree

Question 4

Bronchiolitis

Answer 4

affects small elements of the tracheobronchial tree

disease of infancy

Question 5

Acute Bronchitis

Answer 5

MC caused by respiratory viruses

self limiting

avoid antibiotics

rare indications for cough suppressants

sx:
lethargy, malaise
fever (ibuprofen, acetaminophen)
dehydration (fluids)

Question 6

Acute Bronchitis: pathogens

Answer 6

common cold viruses: rhinovirus, coronavirus

majority: influenza, adenovirus
children: parainfluenza

secondary bacterial infections may be involved

bacterial: mycoplasma pneumoniae
also: chlamydophila pneumoniae, b pertussis, s pneumoniae, streptococcus, staphylococcus, haemophilus, moraxella catarrhalis, mycobacterium tuberculosis

Question 7

Acute Bronchiolitis

Answer 7

respiratory synctial virus (RSV)

infants: 0-1yr

self limiting

Question 8

Acute Bronchiolitis: treatment (outpatient)

Answer 8

treat fever
oral fluids
observe for deterioration

Question 9

Acute Bronchiolitis: treatment (severe)

Answer 9

oxygen therapy
IV fluids

aerosolized bronchodilators

ribavirin

• AAP does not recommend routine use
• may benefit pts with bronchopulmonary dysplasia, congenital heart disease, prematurity, IM

Question 10

Acute Bronchiolitis: prophylaxis

Answer 10

Against RSV with underlying pulmonary/cardiovascular disease

monthly RSV Ig or palivizumab during RSV season (late fall, winter, early spring)

Question 11

Palivizumab

Answer 11

monoclonal antibody

ADEs:

• fever
• rash
• antibody formation
• anaphylaxis (angioedema, dyspnea, hypotonia, pruritus, respiratory failure, unresponsiveness, urticaria)
• thrombocytopenia

Question 12

Chronic Bronchitis: causes

Answer 12

inhalation of noxious agents (cigarette smoke, occupational dust, fumes, environmental pollution)

genetic factors

bacterial (possibly viral) infections

Question 13

Chronic Bronchitis: hallmark of disease

Answer 13

chronic cough

excessive sputum production

expectoration (microorganism in sputum)

Question 14

Chronic Bronchitis: treatment

Answer 14

chest physiotherapy, humidification of air (mobilize sputum expectoration)

oxygen

bronchodilator

antibiotic

Question 15

Anthonisen Criteria

Answer 15

will the patient benefit from antibiotics

2 of 3

• inc SOB
• inc sputum volume
• production of purulent sputum

Question 16

Chronic Bronchitis: common pathogens

Answer 16

H influenza
M catarrhalis
S pneumoniae
E coli
Enterobacter
Klebsiella (alcoholics)
P aeruginosa

Question 17

Pneumonia: signs and symptoms

Answer 17

abrupt onset fevers, chills, dyspnea, productive cough

rust colored sputum

pleuritic chest pain

Question 18

Pneumonia: physical exam

Answer 18

tachypnea, tachycardia

dullness to percussion

inc tactile fremitus, pectoriloquy, egophony

chest wall retractions, grunting expirations

diminished breath sounds

inspiratory crackles

Question 19

Pneumonia: diagnostics

Answer 19

chest x-ray: dense lobar/segmental infiltrate

labs:

• leukocytosis w/ predominant polymorphonuclear cells
• low SaO2

Question 20

Community Acquired Pneumonia

Answer 20

MC pathogen: S pneumoniae

M pneumoniae
legionella
C pneumoniae
H influenza
viruses (influenza)

Question 21

Community Acquired Pneumonia: pathogens

Answer 21

MC pathogen: S pneumoniae

M pneumoniae
legionella
C pneumoniae
H influenza
viruses (influenza)

Question 22

Community Acquired Pneumonia: treatment

Answer 22

antibiotics

humidified oxygen (hypoxemia)

bronchodilators (bronchospasm)

fluids

chest physiotherapy (respiratory secretions)

Question 23

Pneumonia: previously healthy (pathogen, therapy)

Answer 23

S pneumoniae
M pneumoniae
H influenzae
C pneumoniae
M catarrhalis

macrolide/azalide
or
tetracycline

Question 24

Pneumonia: comorbidities (pathogen, therapy)

Answer 24

viral
MDR S pneumoniae

oseltamivir or zanamivir (<48 from sx onset)

fluoroquinolone
or
beta lactam + macrolide

Question 25

Pneumonia: elderly, >25% macrolide resistant S pneumoniae (pathogen, therapy)

Answer 25

S pneumoniae gram negative bacilli ``` piperacillin/tazobactam or cephalosporin or carbapanem ``` fluoroquinolone or beta lactam + macrolide + tetracycline

Question 26

Pneumonia: Non ICU (pathogen, therapy)

Answer 26

``` S pneumoniae H influenzae M pneumoniae C pneumnoiae legionella ``` fluoroquinolone or beta lactam + macrolide/tetracycline

Question 27

Pneumonia: ICU (pathogen, therapy)

Answer 27

S . pneumoniae, S. aureus, Legionella sp., gram-negative bacilli, H. influenza P. aeruginosa MRSA Viral β-Lactam + macrolideb/fluoroquinoloned Piperacillin-tazobactam or meropenem or cefepime + fluoroquinoloned/AMG/azithromycin; or β-lactam + AMG + azithromycin/respiratory fluoroquinoloned Above + vancomycin or linezolid Oseltamivir or zanamivir ± antibiotics for 2° infection

Question 28

Pneumonia: pediatrics (pathogens)

Answer 28

MC: RSV, parainfluenza, adenovirus older children: M pneumoniae ``` beyond neonatal: MC: S pneumoniae group A streptococcus S aureus H influenza B ```

Question 29

Pneumonia: prevention guidelines

Answer 29

A: - vaccinations (influenza, pneumonia) - prophylaxis (influenza) - within 48hr of sx (influenza): amantadine, rimantadine, oseltamivir, or zanamivir B: - pertussis prophylaxis (macrolide) - single dose vials for nebulizers