Antimicrobial Stewardship (AMS)

Resources to help you ensure the safe and effective use of antimicrobials in NSHA patients.

Community-Acquired Pneumonia (Adult)

Community-acquired pneumonia (CAP):  acute infection acquired outside of hospital or within 48 hours of admission

Last revised March 2020

  • Viruses are common causative pathogens and frequently implicated in co-infections with bacteria.
  • The most common bacterial pathogen is Streptococcus pneumoniae.
    • Less common bacteria: Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus, Legionella pneumophila, Enterobacterales (Enterobacteriaceae), Mycoplasma pneumoniae

Last updated March 2020

  • Differential diagnoses: acute exacerbation of COPD, acute bronchitis, heart failure, and pulmonary embolism
  • Infiltrate on chest radiograph with supportive clinical findings:
    • Symptoms include new onset fever, cough, sputum production, dyspnea, tachypnea, pleuritic chest pain 
    • Physical findings consistent with signs of air space disease (e.g. crackles, bronchial breath sounds)
    • If no infiltrate on initial x-ray, patients should be reassessed within 48 to 72 hours if a high clinical suspicion of pneumonia remains
  • Risk stratify using clinical judgement or the CRB-65 score:
CRB-65: Patient Criteria Points
Confusion (either based on specific mental test OR new disorientation to person, place or time) 1
Respiratory rate > 30 breaths per minute 1
Hypotension (systolic < 90 mm Hg OR diastolic < 60 mm Hg) 1
Age > 65 years old 1

⇩

CRB-65 Score 30 Day Mortality Management Setting
0 points AND O2 sat > 92% (on room air) 2.4 % (low risk) Outpatient treatment
1 – 2 points 13.3 % (moderate risk) Consider admission to inpatient ward
3 – 4 points 34.3 % (high risk) Often requires an ICU admission

Last reviewed March 2020

  • This guideline does not apply to patients with cystic fibrosis, febrile neutropenia, structural lung disease, and others colonized with multidrug-resistant microorganisms.
  • Macrolides (e.g. azithromycin) are not first line because of poor S. pneumoniae coverage
  • Consider testing for Legionella urinary antigen in severe CAP (requiring ICU admission) or if patient is associated with a local Legionella outbreak
  • Influenza testing: recommended for CAP requiring hospital admission during periods of high influenza activity
  • Sputum cultures if any one of:
    • ICU admission requiring intubation, starting empiric treatment for or recent infection with MRSA or resistant Gram-negatives (e.g. Pseudomonas), hospitalization and receipt of parenteral antibiotics in the last 90 days, or copious sputum production
    • Low quality results may be misleading as cultured bacteria often represent colonization 
  • Blood cultures if any one of:
    • Fever, ICU admission requiring intubation, starting empiric treatment for or recent infection with MRSA or resistant Gram-negatives (e.g. Pseudomonas), or hospitalization and receipt of parenteral antibiotics in the last 90 days
  • Empiric coverage of atypical bacteria (e.g. Legionella, Mycoplasma):
    • Outpatient setting: not recommended
    • Non-ICU hospitalization: benefit is unclear and there is risk of adverse effects, especially in patients with a predisposition for QTc prolongation from macrolides (i.e. azithromycin) and multiple adverse effects from fluoroquinolones (i.e. levofloxacin)
    • ICU patients:  coverage for Legionella is routinely recommended (see below)
  • Aspiration pneumonia
    • Antimicrobial prophylaxis at the time of aspiration is not beneficial. Provide supportive care and reassess in 48 hours for signs and symptoms of pneumonia
    • Routine addition of anaerobic coverage, such as metronidazole, is not recommended unless treating an empyema or lung abscess.

Last reviewed March 2020

*May require renal dose adjustments.

Note: amoxicillin/clavulanate unnecessarily broad for most community acquired pneumonia in previously healthy individuals.
  • Oseltamivir 75 mg PO BID x 5 days (dose adjust in renal dysfunction) recommended as empiric treatment in hospitalized patients with suspicion of influenza, regardless of timing of symptom onset. See influenza guideline.

 

Last reviewed March 2020

Usual duration is 5 days, exceptions include:

  • The patient is not yet clinically stable: ongoing vital sign abnormalities including tachycardic, tachypnea, hypotension, high oxygen requirements, or persistent fever
  • Associated bloodstream infections
  • Duration in cases of S. aureus or in known resistant Gram negative bacteria is at least 7 days; ID consultation should be considered
  • Longer durations required for empyema and lung abscess

Last reviewed March 2020

  • Review IV antibiotics within 48 hours of treatment initiation and consider switching to PO antibiotics once patient is clinically improving (e.g. afebrile, hemodynamically stable, adequate PO intake).
    • CAP is often inappropriately treated with prolonged IV therapy and prolonged antibiotic courses.
  • If tuberculosis is a concern, fluoroquinolones can interfere with TB cultures and should be avoided
  • If colonized/infected with nontuberculous mycobacteria (NTM), avoid macrolides since resistance can develop

Last reviewed March 2020

1. Jain S, Self WH, Wunderink RG, Fakhran S, Balk R, Bramley AM, et al. Community-Acquired Pneumonia Requiring Hospitalization among U.S. Adults. N Engl J Med. 2015; 373;5: pp 415-427.

2. Metlay JP, Waterer GW, Long AC, Anzueto A, Brozek J, Crothers K, et al. Diagnosis and Treatment of Adults with Community-acquired Pneumonia. Am J Respir Crit Care Med. 2019; Vol 200 (Iss 7): pp 809-821.

3. National Institute for Health and Care Excellence. Pneumonia (community-acquired): antimicrobial prescribing. NICE Guideline. 2019. www.nice.org.uk/guidance/ng138. Accessed September 18, 2019

4. Antibiotics Why and Why Not 2018 Dalhousie CPD Academic Detailing Service, November 2018. http://www.medicine.dal.ca/departments/core-units/cpd/programs/academic-detailing-service.html. Accessed August 12, 2019

5. Management of Community Acquired Pneumonia in Adults. SHS + UHN Antimicrobial Stewardship Program, 2018. https://www.antimicrobialstewardship.com/community-acquired-pneumonia. Accessed August 19, 2019.

Last reviewed March 2020

Hospital-Acquired Pneumonia

Hospital-acquired pneumonia (HAP): pneumonia not present at the time of hospital admission and occurring ≥ 48 hours after admission

Last reviewed April 2020

  • Streptococcus pneumoniae
  • Staphylococcus aureus
  • Haemophilus influenzae
  • Gram-negative bacilli
    • Escherichia coli, Klebsiella spp., Enterobacter spp., Serratia spp., Pseudomonas aeruginosa

Last reviewed April 2020

  • Sputum culture
  • Blood cultures (aerobic and anaerobic) x 2 sets using two sites, at least one from peripheral site
  • Suspect HAP if
    • Chest imaging shows new pulmonary infiltrate, PLUS one of:
      • Fever
      • Purulent respiratory secretions
      • Leukocytosis
      • Dyspnea or increase in oxygen requirements

Last reviewed April 2020

  • Usual duration of therapy is 7 days
  • Longer duration indicated for abscess, empyema, or severely immunocompromised

Last reviewed April 2020

  • Therapy should be tailored once culture and sensitivity results or other diagnostic information becomes available.
  • Aspiration pneumonitis: antimicrobial therapy is not indicated for acute macroaspiration events. Pneumonia may develop, reassess after 48 hours.            
  • Aspiration pneumonia: routine addition of anaerobic coverage, such as metronidazole, is not recommended unless treating an empyema or lung abscess.
  • Consider double antimicrobial coverage for Pseudomonas only if critically ill with high suspicion of infection with resistant microorganism in patients who have receieved recent broad spectrum antimicrobial therapy. Narrow to single agent once sensitivities available.

Last reviewed April 2020

  • Review patient’s prior culture results and prior antibiotic use to inform empiric choices

 

Risk Factors Regimen
  • No rapid clinical deterioration
  • Not admitted to ICU
  • No IV antibiotic use within preceding 90 days

Ceftriaxone 1 g IV q24h

OR

Amoxicillin-clavulanate* 875 mg PO BID

OR

Levofloxacin* 750 mg PO/IV q24h

Any ONE of the following:

  • HAP requiring ICU management: septic shock and/or intubation
  • Colonization or prior infection with Pseudomonas or other resistant Gram-negative bacilli (e.g. extended spectrum beta-lactamase producing E. coli, Klebsiella)
  • Prolonged hospitalization (>2 weeks)
  • IV antibiotic use within 90 days

Piperacillin-tazobactam* 3.375g IV q6h†

OR

Meropenem* 500 mg IV q6h

Preferred if: colonized/infected with piperacillin-tazobactam resistant microorganism OR IgE mediated penicillin allergy

If MRSA suspected:

  • Known MRSA colonization
  • Previous MRSA infection

ADD:

Vancomycin* IV

(See NSHA Antimicrobial Handbook or Spectrum App)

*May require renal dose adjustments, see NSHA Spectrum app or dosing table

†Critical care may have a prolonged infusion protocol

 

 

Last reviewed April 2020

1. Kalil AC, Metersky ML, Klompas M, Musced-ere J, Sweeney DA, Palmer LB, et al. Management of Adults With Hospital-Acquired and Ventilator-Associated Pneumonia: 2016 Clinical Practice Guidelines by the Infectious Diseases Society of America and the American Thoracic Society. Clin Infect Dis. 2016; 63: pp e61-e111.

2. National Institute for Health and Care Excellence. Pneumonia (hosptial-acquired): antimicrobial prescribing. NICE Guideline. 2019. www.nice.org.uk/guidance/ng138. Accessed March 13, 2020.

3. Management of Hospital-Acquired Pneumonia in Adults. SHS + UHN Antimicrobial Stewardship Program, 2018. https://www.antimicrobialstewardship.com/community-acquired-pneumonia. Accessed March 13, 2020.

4. Treatment Guidelines. Sunnybrook Health Sciences Centre. https://sunnybrook.ca/content/?page=antimicrobial-stewardship-treatment-guidelines. Accessed April 5, 2020.

Last reviewed April 2020

Ventilator-Associated Pneumonia in Adults

Ventilator-associated pneumonia (VAP): pneumonia occurring ≥ 48 hours after mechanical ventilation

Last reviewed April 2020

  • Staphylococcus aureus
  • Haemophilus influenzae
  • Gram-negative bacilli
    • Escherichia coli, Klebsiella spp., Enterobacter spp., Serratia spp., Pseudomonas aeruginosa

Last reviewed April 2020

  • Sputum culture
    • Endotracheal aspiration is generally preferred over invasive sampling (e.g. bronchoalveolar lavage)
  • Blood cultures (aerobic and anaerobic) x 2 sets using two sites, at least one from peripheral site
  • Suspect VAP if
    • Chest imaging shows new pulmonary infiltrate, PLUS one of:
      • Fever
      • Purulent respiratory secretions
      • Leukocytosis
      • Increase in oxygen requirements or ventilatory settings

Last reviewed April 2020

  • Usual duration of therapy is 7 days
  • Longer duration indicated for abscess, empyema, or severely immunocompromised

Last reviewed April 2020

  • Antimicrobial therapy should be narrowed based on microbiology of respiratory samples.
  • Stenotrophomonas maltophilia can cause VAP and should be suspected if patients is not improving despite broad-spectrum antimicrobial therapy. Trimethoprim/sulfamethoxazole is the antibiotic of choice.
  • Candida is a very rare cause of pneumonia and does not require treatment unless evidence of systemic infection such as bloodstream infection.
  • Respiratory cultures can continue to be positive despite successful treatment; avoid repeating cultures if patient is clinically improving.
  • Consider double antimicrobial coverage for Pseudomonas only if critically ill with high suspicion of infection with resistant microorganism in patients who have receieved recent broad spectrum antimicrobial therapy. Narrow to single agent once sensitivities available.

Last reviewed April 2020

1. Kalil AC, Metersky ML, Klompas M, Musced-ere J, Sweeney DA, Palmer LB, et al. Management of Adults With Hospital-Acquired and Ventilator-Associated Pneumonia: 2016 Clinical Practice Guidelines by the Infectious Diseases Society of America and the American Thoracic Society. Clin Infect Dis. 2016; 63: pp e61-e111.

2. National Institute for Health and Care Excellence. Pneumonia (hosptial-acquired): antimicrobial prescribing. NICE Guideline. 2019. www.nice.org.uk/guidance/ng138. Accessed March 13, 2020.

3. Ventilator-Associated Pneumonia. SHS + UHN Antimicrobial Stewardship Program, 2020. https://www.antimicrobialstewardship.com/community-acquired-pneumonia. Accessed March 13, 2020.

Last reviewed April 2020