IC16: LRTI Flashcards
What are the typical causative pathogens for outpatient CAP? State the most common pathogen as well.
1) Streptococcus pneumoniae (most common)
2) Haemophilus influenzae
3) Atypical organisms, e.g. Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella pneumophilia
What additional pathogens may need to be covered for inpatient non-severe CAP?
Based on risk factors for MDROs, consider if need MRSA and Pseudomonas cover
What pathogens need to be covered for inpatient severe CAP?
1) Streptococcus pneumoniae
2) Haemophilus influenzae
3) Atypical organisms, e.g. Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella pneumophilia
4) S. Aureus (MSSA)
5) Other Gram‐negative bacilli, e.g. Klebsiella pneumonia, Burkholderia pseudomallei
6) Based on risk factors for MDROs, consider if need MRSA and Pseudomonas cover
What other illness should be considered and tested for all inpatients during circulating season?
Influenza
What does the risk stratification for CAP determine?
1) Location of treatment
* Outpatient versus inpatient (non‐ICU versus ICU)
2) Organisms that need to be covered
3) Empiric antibiotic selection
4) Route of antibiotic administration
What are the risk stratification strategies that can be employed to determine site of treatment for a patient with CAP?
1) Pneumonia Severity Index (PSI)
2) CURB-65 + IDSA Criteria for severe CAP
_____ is preferentially recommended over _____ in IDSA CAP guidelines as a risk stratification strategy?
Pnemonia Severity Index, CURB 65
How many mortality risk classes are there in PSI and what are the recommendations for location of CAP treatment for each class?
Class I and II: Treat in outpatient
Class III: short hospitalisation or observation
Class IV and V: Treat in inpatient
What are the components of CURB-65?
1) Confusion (New onset)
2) Urea > 7 mmol/L (Uremia)
3) Respiratory Rate ≥ 30 breaths/min
4) Blood pressure (hypotension; SBP < 90 mmHg or DBP < 60 mmHg)
5) Age ≥ 65 years
Relate the CURB-65 score to location of treatment of CAP
Score 0 or 1 = Can be managed in outpatient
Score 2 = manage in inpatient (short term hospitalisation or observation)
Score ≥ 3 = manage in inpatient, consider ICU
What are the major criteria for severe CAP?
1) Mechanical ventilation
2) Septic shock requiring vasoactive medications (hemodynamic instability)
How is severe CAP defined by IDSA guidelines?
Severe CAP = ≥ 1 major criteria or ≥ 3 minor criteria
What are the minor criteria for severe CAP? (total 8)
- RR ≥ 30 breaths/min
- PaO2 /FiO2 ratio ≤ 250 (fraction of inspired oxygen; typically need ICU monitoring and mechanical ventilation also)
- Multilobar infiltrates
- Confusion/ disorientation (common in elderly)
- Uremia (urea ≥ 7 mmol/L)
- Leukopenia (WBC < 4 x 10^9/L) (must not be due to chemotherapy)
- Hypothermia (core temperature < 36°C)
- Hypotension requiring aggressive fluid resuscitation
State the possible empiric regimen(s) for CAP for a patient with CURB score 1 and no significant PMH. State the pathogen(s) to be targeted. State anything special about the regimen if any.
β-lactam: Amoxicillin 1g q8H (High dose used in case of resistant S. pneumoniae)
If penicillin allergy: Respiratory Fluoroquinolone (Levofloxacin or Moxifloxacin)
Pathogen targeted: S. Pneumonia
State the possible empiric regimen(s) for CAP for a patient with CURB score 1 and with significant PMH of HTN, DM, asthma etc. State the pathogen(s) to be targeted.
β-Lactam (Augmentin or Cefuroxime) + Macrolide (Clarithromycin or Azithromycin) OR Doxycycline
Alternative: Levofloxacin or Moxifloxacin (if Penicillin allergy)
Pathogens targeted:
S. pneumoniae, H. influenzae, Atypicals
State the possible empiric regimen(s) for CAP for a patient with CURB score 2 and no significant PMH. State the pathogen(s) to be targeted.
β-Lactam (Augmentin or Cefuroxime or Ceftriaxone) + Macrolide (Clarithromycin or Azithromycin) OR Doxycycline
Alternative: Levofloxacin or Moxifloxacin (if Penicillin allergy)
Pathogens targeted:
S. pneumoniae, H. influenzae, Atypicals
State the possible empiric regimen(s) for CAP for a patient with CURB score 2 with risks of Pseudomonas.
1) Piperacillin/ tazobactam (+ Macrolide/ Doxy for atypical cover)
2) Ceftazidime (does not cover S. pneumoniae -> cannot use on it’s own)
3) Cefepime (+ Macrolide/ Doxy; for atypical cover)
4) Meropenem (+ Macrolide/ Doxy; for atypical cover)
5) Levofloxacin (can monotherapy if not targeting S. Aureus, need combination if targeting S. Aureus)
Which antibiotics are used to target Burkholderia Pseudomallei
Ceftazidime or Meropenem
Which antibiotic cannot be used for severe CAP although it can be used for all other less severe CAP and why?
Doxycycline (No easily accessible IV formulation)
Which of the FQs have anaerobic cover?
Moxifloxacin
