SUMMARY:

The American College of Physicians (ACP) addresses the use of antibiotics for common infections (COPD, community-acquired pneumonia, UTIs, and cellulitis). Evidence-based, the overall purpose of this document is to “describe appropriate use of shorter durations of antibiotic therapy for common bacterial infections seen in both inpatient and outpatient health care settings.”

KEY POINTS:

• Antibiotics/antimicrobials are prescribed in 10% of all outpatient PCP visits
  • 30% of these prescriptions are unnecessary and continue for longer than needed
  • Overuse causes antibiotic resistance and “adverse events” in 20% of patients | Considered a national threat by ACP and the CDC
• Definition of appropriate antibiotic use: “Right antibiotic at the right dose for the right duration”
• Current guidelines support shortening the duration of antibiotic use
  • However, to prevent antibiotic resistance, many physicians prescribe longer courses of treatment, irrespective of the condition (around 10 days)
• Resistance
  • Evidence shows that there is no correlation between shorter course of antibiotics and increased resistance
  • Due to “natural selection,” resistance is more likely to occur with longer course therapy

COPD Exacerbation and Acute Uncomplicated Bronchitis

Bronchitis

• Antibiotics are not recommended unless there is suspicion of pneumonia

COPD

• Antibiotics are recommended due to high risk of underlying bacterial infection
• Global Initiative for Chronic Obstructive Lung Disease (GOLD) recommends
  • Treating COPD with antibiotics if an underlying bacterial infection is suspected needs 2 out of 3 criteria
    • Increased shortness of breath
    • Increased sputum volume
    • Purulence
  • Limit to 5 days of therapy

Community-Acquired Pneumonia

• Antibiotics are recommended for a minimum of 5 days (American Thoracic Society/IDSA guideline)
  • However, when determining length of treatment, consider validated measures of clinical stability (e.g., resolution of vital sign abnormalities, ability to eat, and normal mentation)
• Evidence suggests that every additional day of treatment is associated with a 5% increased risk for an “adverse event”

Uncomplicated Cystitis and Pyelonephritis

• UTIs
  • Most common bacterial infection that presents for medical attention
  • Infectious cystitis primarily caused by Escherichia coli (75% of bacterial cases)
• Therapy durations based on antibiotic type
  • Nitrofurantoin: 5 days
  • TMP–SMX: 3 days
  • Fosfomycin: Single dose
• Fluoroquinolones
  • 3-day administration
  • Due to adverse events, reserve use for patients with history of resistant organisms
• Pyelonephritis
  • IDSA/ESCMID (European Society of Clinical Microbiology and Infectious Diseases) guideline only addresses female patient
  • ACP Recommendation (not hospitalized, males and females): Oral fluoroquinolone for 7 days or TMP–SMX for 14 days | TMP–SMX should not be used as the only therapy without “culture and susceptibility testing in pyelonephritis”
  • Some clinical trials have showed that fluroquinolones can effectively be reduced to 5 days (cure rate of 93%; noninferior studies comparing 5-day course to 10-day course)
  • Recommendations for a shorter course of TMP–SMX are not yet determined | More clinical trials are needed

Note: UTIs in pregnant women, complicated UTIs (related to “structural or functional abnormalities” in the urinary tract), and acute bacterial prostatitis are not covered in this best practice statement

Cellulitis

• Nonpurulent cellulitis
  • Usually caused by streptococci
• Add methicillin-resistant Staphylococcus aureus coverage for the following
  • Purulent cellulitis
  • Cellulitis associated with
    • Penetrating trauma | Evidence of MRSA infection elsewhere | Nasal colonization with MRSA | IV drug use | Systemic inflammatory response syndrome
• IDSA guideline (2014)
  • Recommends that “patients should receive antibiotics for uncomplicated cellulitis but that clinicians should consider extending treatment if the infection has not improved after 5 days”
• NICE (2019)
  • Recommends treatment for 5 to 7 days
• More studies are needed to further clarify the best duration of antibiotic treatment for soft tissue infections (SSTIs)

Note: Purulent SSTIs such as furuncles, carbuncles, and abscesses, usually require incision and drainage and are not addressed in this document

Learn More – Primary Sources:

Annals of Internal Medicine: Appropriate Use of Short-Course Antibiotics in Common Infections: Best Practice Advice From the American College of Physicians