Lower Respiratory Tract Infection

Question 1

What is the definition of acute bronchitis?

Answer 1

acute cough <3w due to inflammation of trachea and lower airways

Question 2

are antibiotics recommended in the treatment of acute bronchitis?

Answer 2

No

Question 3

How does acute bronchitis usually start?

Answer 3

from a viral URTI

Question 4

What are the expected radiographic findings for pneumonia?

Answer 4

evidence of new infiltrates / dense consolidations, usually unilateral

Question 5

What urinary antigen tests are available for pneumonia?

Answer 5

s. pneumonia, legionella

Question 6

What are the limitations of urinary antigen tests for pneumonia?

Answer 6

only indicates exposure, remains positive even with appropriate treatment

Question 7

For whom are urinary antigen tests recommended?

Answer 7

severe CAP or hospitalised patients

Question 8

For whom should pre-treatment blood and respiratory cultures be obtained?

Answer 8

Patients in the hospital who have:
- Severe CAP
- have MRSA and pseudomonas risk factors (being empirically treated for either, infected with either in the past 1 year, hospitalised or received IV antibiotics in the last 90 days)

Question 9

What are the risk factors for pneumonia?

Answer 9

• smoking
• chronic lung condition
• immunosuppression
• swallowing impairment (increased risk of aspiration)

Question 10

What is the definition of community-acquired pneumonia?

Answer 10

Onset in the community / < 48H after admission

Question 11

Outline the CURB-65 risk stratification tool.

Answer 11

Confusion
Urea > 7mm
Respiratory rate >=30
SBP < 90 / DBP < 60
Age >= 65
0-1: outpatient treatment
2: inpatient treatment
>=3: inpatient, consider ICU

Question 12

What are the 2 major criteria for severe CAP?

Answer 12

• mechanical ventilation
• septic shock requiring vasoactive medications

Question 13

What are the 8 minor criteria for severe CAP?

Answer 13

• Urea > 7
• Respiratory rate >= 30
• PaO2/FiO2 <= 250
• multilobar infiltrates
• confusion
• WBC < 4
• hypothermia < 36c
• hypotension requiring aggressive fluid resuscitation

Question 14

What pathogen(s) is/are implicated in patients with CAP with no comorbidities treated in the outpatient setting?

Answer 14

s. pneumoniae

Question 15

What are the recommended regimens for patients with CAP with no comorbidities treated in the outpatient setting?

Answer 15

PO amoxicillin 1g Q8H OR levofloxacin / moxifloxacin

Question 16

What pathogen(s) is/are implicated in patients with CAP with comorbidities treated in the outpatient setting?

Answer 16

s. pneumoniae, h. influenzae, atypical bacteria

Question 17

What are the recommended regimens for patients with CAP with comorbidities treated in the outpatient setting?

Answer 17

PO amox-clav / PO cefuroxime AND clarithromycin / azithromycin / doxycycline OR respiratory fluoroquinolones

Question 18

What pathogen(s) is/are implicated in patients with non-severe CAP treated in the inpatient setting?

Answer 18

s. pneumoniae, h. influenzae, atypical bacteria

Question 19

What are the MRSA risk factors for patients with non-severe CAP treated in the inpatient setting?

Answer 19

Respiratory isolation of MRSA in the past 1 year / prior hospitalisation or abx use in the last 90 days AND MRSA PCR screen positive

Question 20

What are the pseudomonas risk factors for patients with non-severe CAP treated in the inpatient setting?

Answer 20

respiratory isolation of pseudomonas in the last 1 year

Question 21

What agents should be included in the treatment of patients with non-severe / severe CAP with MRSA risk factors?

Answer 21

IV Vancomycin / IV/PO linezolid

Question 22

What agents may be considered in the modification of treatment of patients with non-severe CAP with pseudomonas risk factors?

Answer 22

pip-tazo, meropenem, cefepime, ceftazidime, levofloxacin

Question 23

What are the MRSA risk factors for patients with severe CAP treated in the inpatient setting?

Answer 23

respiratory isolation of MRSA in the past 1 year OR prior hospitalisation or abx use in the last 90 days

Question 24

What are the pseudomonas risk factors for patients with severe CAP treated in the inpatient setting?

Answer 24

respiratory isolation of pseudomonas in the past 1 year OR prior hospitalisation or abx use in the last 90 days

Question 25

What pathogen(s) is/are implicated in patients with severe CAP treated in the inpatient setting?

Answer 25

s. pneumoniae, h. influenzae, atypical, gram neg (klebsiella, burkholderia), s. aureus

Question 26

What agents should be added in patients with lung abscess / empyema?

Answer 26

metronidazole (first choice) / clindamycin

Question 27

what are the recommended treatment regimens for non-severe CAP treated in the inpatient setting?

Answer 27

1. IV amox-clav / cefuroxime / ceftriaxone + azithromycin / clarithromycin / doxycycline 2. respiratory fluoroquinolone

Question 28

what are the recommended treatment regimens for severe CAP treated in the inpatient setting?

Answer 28

IV amox-clav / penicillin G + ceftazidime + azithromycin / clarithromycin OR respiratory fluoroquinolone + ceftazidime (ceftazidime is for burkholderia)

Question 29

Why are respiratory fluoroquinolones not first-line for the treatment of pneumonia?

Answer 29

- high adverse effects - mask symptoms of TB - collateral damage with 3rd / 4th gen cephalosporins

Question 30

What should be added to pneumonia treatment if influenza is suspected?

Answer 30

Oseltamivir

Question 31

For CAP de-escalation, abx covers for which bacteria can be dropped, if there are no available cultures?

Answer 31

MRSA, pseudomonas, burkholderia

Question 32

What is the recommended treatment duration for CAP?

Answer 32

minimum 5d, 7d for MRSA / pseudomonas suspected / proven longer for deep-seated infections and uncommon pathogens

Question 33

When should chest x-ray be repeated?

Answer 33

only if there is a deterioration in the patient's condition

Question 34

What is the definition of HAP / VAP?

Answer 34

onset >= 48H after admission / mechanical ventilation

Question 35

What are the risk factors for HAP and VAP?

Answer 35

as per pneumonia + supine position, deep sedation, prior abx use, opiods, mechanical ventilation

Question 36

What pathogens should be empirically covered for HAP / VAP?

Answer 36

pseudomonas and s. aureus

Question 37

What are the MRSA risk factors for HAP / VAP?

Answer 37

- isolation of MRSA in the last 1 year - prior IV abx use within the last 90 days - hospital unit > 20% of s. aureus is MRSA - patient is at high risk for mortality

Question 38

When should double pseudomonal cover be considered?

Answer 38

1. patient has risk factors for pseudomonal resistance (prior IV abx use, isolation of pseudomonas in the last 1 year, acute renal replacement therapy prior to VAP onset) 2. hospital unit where >10% of pseudomonas is resistant to agent considered for monotherapy 3. patient is at high risk for mortality

Question 39

Should aminoglycosides be used as monotherapy?

Answer 39

no

Question 40

What are the recommended regimens for HAP / VAP?

Answer 40

pip-tazo / cefepime / ceftazidime / meropenem / imipenem AND/OR anti-pseudomonal FQ OR amikacin

Question 41

What is the recommended treatment duration for HAP / VAP?

Answer 41

7 days regardless of pathogen

Question 42

For de-escalation in HAP / VAP, what pathogen cover should be maintained if culture / antibiogram is not available?

Answer 42

pseudomonas, s. aureus, enteric gram neg (can drop MRSA if no MRSA in culture, unless patient very sick)