lower URTI

Question 1

acute bronchitis duration (Cough)

Answer 1

at least 3 weeks
*use of antibiotics does not hasten resolution

Question 2

is antibiotics indicated for bronchitis

Answer 2

only if complications suspected (further diagnostic test required to confirm bacterial infection)

Question 3

When to refer to Dr for acute bronchitis?

Answer 3

Fever development
SOB/ chest pain
cough increased in extent/ frequency
significant cough persisting >3 weeks
*bacterial superinfection risk

Question 4

pneumonia criteria

Answer 4

CURB-65
Confusion (new onset)
Urea >7mmol/L
Respiratory Rate >30 breaths per min
BP (SBP <90 OR DBP <60)
Age > 65

0-1 inpatient
2 inpatient (nonsevere)
=/>3 inpatient SEVERE

PSI (pneumonia severity index)
class I/II - outpt
class III - short hospitalisation/ observation
Class IV/V - inpt

Question 5

pathogen to cover for community acquired pneumonia, no comorbidities + antibiotics regimen

Answer 5

Strep pneumo ONLY

Amoxicillin 1g q8h
OR
respi FQ (levo 750mg OD/ moxi)

ALL PO

Question 6

CAP with comorbidities in outpatient setting, suggest regimen

Answer 6

Pathogens to cover: Strep pneumo, haemophilus influenzae, atypicals

Suggested regimen: beta-lactam + macrolide/doxycycline (100mg q12h)
amoxi-clav 625mg q8h OR cefuroxime 500mg q12h
+
azithromycin 500mg OD OR clarithromycin 500mg q12h

OR
just respi FQ alone (levo 750mg OD/moxi)

ALL PO, MINIMUM duration 5d
*most pts achieve clinical stability in 1st 48-72h

Question 7

CAP, INPATIENT setting (nonsevere) regimen

Answer 7

as per outpatient with comorbidities
beta-lactam+macrolide/doxycycline // OR just respi FQ (levo 750mg OD/ moxi)

consider MRSA & P. aeruginosa risk factors
MRSA: RESPI isolation of MRSA in last 1 yr // Hospitalisation OR parenteral antibiotic use in last 90d AND MRSA PCR screen positive
- Use IV vanco (25-30mg/kg LD, 15mg/kg q8-12h until 400-600 AUC/MIC) OR IV/PO linezolid (600mg q12h)

P. aeruginosa: RESPI isolation of P. aeruginosa in last 1y
- MODIFY: piptazo / ceftazidime *no strep pneumo coverage/ cefepime/ meropenem 1g q8h/ levo (can monotherapy)
*ALL max normal dose except mero

MINIMUM duration 5d (most pts achieve clinical stability in 1st 48-72h)
IF SUSPECTED MRSA/ P. aeruginosa then 7d

Question 8

CAP, inpatient SEVERE antimicrobial regimen

Answer 8

*BURKHOLDERIA PSEUDOMALLEI coverage - CEFTAZIDIME 2g q8h

same as outpt w comorbidities (strep pneumo, haemo influenzae, atypical) w add on for b. pseudomallei
*beta-lactam: amoxi-clav OR pen G

include MRSA & p. aeruginosa where risk factors indicate possibility (duration 7d) .

• IF LUNG ABSCESS/ EMPYEMA - INCLUDE ANAEROBE COVERAGE
• metronidazole (IV/PO) OR clindamycin (IV/ PO)
  ^deep-seated infection - longer duration (>5d)

Question 9

concurrent influenza with CAP - management for patients

Answer 9

if influenza PCR +ve: start 5d oseltamivir 75mg PO BD ASAP (up to 5th day)
*discontinue at 48-72h if no evidence of bacterial pathogen

*respi FQ: NOT 1st line for CAP (mask symptoms)

Question 10

when to use adjunctive corticosteroid therapy for CAP?

Answer 10

*corticosteroids: reduce inflammation in lungs; NOT routinely added for CAP

ADD IF: patient is shock refractory to fluid resuscitation & vasopressor support
*severe CAP

Question 11

Empiric treatment for Hospital Acquired Pneumonia (HAP)

Answer 11

cover: P. aeruginosa, S. aureus, Enterobacterales (E.coli/ Klebsiella/ Proteus)

*cover MRSA if:
- prior IV abx use <90d
- (respi) isolation of MRSA within last 1y
- Hospitalisation in unit with >20% MRSA (out of all S. aureus cases)
- MRSA prevalence unknown, HIGH risk of mortality

*cover DOUBLE antipseudomonal if ANY ONE OF:
- risk factor for ANTIMICROBIAL RESISTANCE (prior IV abx use <90d/ acute RRT prior to VAP onset/ isolation of PA in last 1y)
- hospitalisation in unit with >10% PA isolates RESISTANT to agents used for monotherapy
- prevalence of PA unknown, pt at HIGH risk of mortality
-> use anti-pseudomonal Beta-lactam (piptazo/ cefepime/ ceftazidime *ESBL risk/ mero/ imi) AND/OR anti-pseudomonal FQ (cipro/levo)

*avoid AGs as SOLE antipseudomonal agent

Duration: 7d (Regardless of pathogen)

Question 12

Monitoring for CAP/HAP

Answer 12

• Response to treatment: most patients achieve clinical stability to treatment within 1st 48-72h
  *elderly/ co-morbidities: may take longer
  *no difference in recurrence & mortality

-DO NOT escalate abx therapy in 1st 72h UNLESS culture-directed/ significant clinical deterioration

• Resolution of symptoms & vital sign abnormalities (temp/ HR/RR/BP/O2 sat.)
  *HAP: baseline mental status
• Repeat of radiographic imaging NOT required (lags behind clinical improvement for resolution) - only repeat if clinical deterioration

Duration of therapy: 5d (CAP), 7d (HAP)
[longer course if complicated with other deep-seated infections eg. lung abscess, meningitis]