What are the recommended guidelines for selecting, dosing, and duration of antibiotic therapy, including antimicrobial stewardship considerations?

Guidelines in Prescribing Antibiotics

Core Principles of Antibiotic Prescribing

Antibiotics should only be prescribed when bacterial infection is confirmed or highly likely, with treatment tailored to the specific pathogen, site of infection, local resistance patterns, and patient risk factors. 1

Diagnostic Rigor Before Treatment

• Obtain appropriate microbiological samples (blood cultures, sputum, urine, wound swabs) before initiating antibiotics whenever possible, though treatment must not be delayed in critically ill patients 1, 2
• Document sepsis parameters including temperature, respiratory rate, pulse, blood pressure, white blood cell count, and C-reactive protein to enable streamlined therapy decisions 1
• Colonization without clinical signs of infection rarely requires antimicrobial treatment 2
• Avoid prescribing antibiotics to "treat" fever alone—investigate the root cause and treat confirmed infections 2

Empirical Therapy Selection

• Base empirical antibiotic choice on three factors: the anatomic site of infection, patient risk factors for multidrug-resistant organisms (recent antibiotic use, hospitalization, healthcare exposure), and local antimicrobial susceptibility patterns 2
• For critically ill patients with sepsis or septic shock, administer broad-spectrum antibiotics within the first hour after obtaining cultures 1
• Treatment guidelines should be evidence-based, multidisciplinary, regularly updated, and compatible with national guidelines where available 1

Dosing Optimization

• Prescribe antibiotics at optimal doses adapted to patient characteristics (age, weight, renal function) and infection severity 1, 2
• For beta-lactam antibiotics, consider extended or continuous infusion to optimize pharmacodynamic targets 1
• Higher doses may be required for infections with elevated minimum inhibitory concentrations or in poorly penetrated sites 1, 2

Duration of Therapy

For intra-abdominal infections with adequate source control, limit antibiotic therapy to 4 days in immunocompetent, non-critically ill patients and up to 7 days in immunocompromised or critically ill patients. 1

• Shorter treatment durations (5-7 days) are increasingly supported for many infections without compromising outcomes 1
• Patients with ongoing signs of infection beyond 7 days warrant diagnostic re-evaluation rather than automatic antibiotic continuation 1
• Streamline or de-escalate therapy at the earliest opportunity based on culture results and clinical response 1, 2

De-escalation and Streamlining

• Transition from empiric broad-spectrum to targeted narrow-spectrum therapy as soon as microbiological results allow 1, 2
• De-escalation is safe in critically ill patients and is associated with reduced mortality when combined with adequate empirical therapy 1
• Stop antibiotics when infection is unlikely or ruled out, even if initially prescribed 2

Antimicrobial Stewardship Measures

Institutional Requirements

• Establish a local Antibiotic Policy and Formulary created through multidisciplinary consultation, regularly updated based on local resistance patterns 1
• Implement restricted lists of key agents, particularly broad-spectrum antibiotics 1
• Measure and benchmark antibiotic consumption with regular discussion among prescribers, pharmacists, and infection specialists 1
• Audit doses, duration, and route of administration through regular cycles 1

Surgical Prophylaxis

• Single-dose surgical prophylaxis is appropriate for the vast majority of procedures 1
• Prophylaxis should not extend beyond 24 hours postoperatively in most cases 1

Combination Therapy

• Use antibiotic combinations only where current evidence demonstrates benefit (e.g., endocarditis, certain resistant organisms) 2
• Avoid routine combination therapy without specific indication 2

Source Control

Drain infected foci and remove infected devices promptly—adequate source control is mandatory for treatment success. 1, 2

• Inability to control the septic source is associated with intolerably high mortality rates 1
• For localized abscesses, percutaneous drainage combined with appropriate antibiotics is preferred 1

Special Considerations

Agents to Avoid or Reserve

• Avoid antibiotics with higher likelihood of promoting resistance (broad-spectrum agents, fluoroquinolones for simple infections) or use them only as last resort 2
• Reserve carbapenems for documented extended-spectrum beta-lactamase producers or inadequate source control 1

High-Risk Situations Requiring Broad Coverage

• Septic shock requires maximal broad-spectrum coverage with carbapenems (meropenem, doripenem, imipenem) or eravacycline 1
• Inadequate or delayed source control warrants escalation to ertapenem or eravacycline 1
• Patients at high risk for community-acquired ESBL-producing Enterobacterales require carbapenem or eravacycline coverage 1

Beta-Lactam Allergy

• For documented beta-lactam allergy in intra-abdominal infections, use eravacycline or tigecycline 1
• Verify true allergy history, as many reported allergies are not IgE-mediated and do not preclude cephalosporin use 1

Multidisciplinary Approach

• Establish local antimicrobial stewardship teams including infectious diseases specialists, clinical microbiologists, hospital pharmacists, and infection control practitioners 1, 2
• Ensure transparent proceedings of drug and therapeutics committees with declared conflicts of interest 1
• Provide 24-hour access to antimicrobial expertise for complex cases 1

Common Pitfalls to Avoid

• Do not prescribe antibiotics for viral infections or colonization without clinical infection 2, 3
• Do not continue empirical broad-spectrum therapy when cultures are negative or show susceptible organisms 1, 2
• Do not extend treatment duration beyond evidence-based recommendations "just to be safe" 1
• Do not use antibiotics as a substitute for accurate diagnosis in the absence of clear infection 1
• Do not delay obtaining cultures in stable patients, but never delay treatment in critically ill patients 1