What is the empiric treatment?

From the Guidelines

Empiric treatment should be initiated with broad-spectrum antibiotics that cover the most likely pathogens based on the patient's presentation, site of infection, and local resistance patterns, with the goal of minimizing morbidity, mortality, and improving quality of life. When starting empiric treatment, it is essential to consider the patient's factors, including age, comorbidities, recent antibiotic use, and severity of illness. For community-acquired pneumonia, a common empiric regimen includes azithromycin 500mg on day 1, then 250mg daily for 4 days, or doxycycline 100mg twice daily for 5-7 days, as recommended by the guidelines for the management of adults with community-acquired pneumonia 1.

For other types of infections, such as urinary tract infections or skin and soft tissue infections, other antibiotic regimens may be more appropriate. For example, nitrofurantoin 100mg twice daily for 5 days or trimethoprim-sulfamethoxazole 160/800mg twice daily for 3 days are suitable options for urinary tract infections, while cephalexin 500mg four times daily for 5-10 days is often effective for skin and soft tissue infections. It is crucial to reassess therapy after 48-72 hours when culture results become available and narrow the spectrum of antibiotics accordingly to minimize antibiotic resistance, adverse effects, and healthcare costs 1.

The choice of empiric antimicrobial therapy depends on complex issues related to the patient’s history, clinical status, and local epidemiologic factors, and should be tailored to the individual patient's needs. The Surviving Sepsis Campaign guidelines recommend empiric broad-spectrum therapy with one or more antimicrobials for patients presenting with sepsis or septic shock to cover all likely pathogens, including bacterial and potentially fungal or viral coverage 1.

Key considerations in selecting empiric therapy include:

• The nature of the clinical syndrome/site of infection
• The patient's history, including recent antibiotic use and comorbidities
• Local epidemiologic factors, such as the prevalence of antibiotic-resistant organisms
• The severity of illness, with more severe infections requiring broader-spectrum therapy

By considering these factors and choosing the most appropriate empiric antibiotic regimen, healthcare providers can minimize morbidity, mortality, and improve quality of life for patients with infections.

From the FDA Drug Label

To reduce the development of drug-resistant bacteria and maintain the effectiveness of levofloxacin tablets and other antibacterial drugs, levofloxacin tablets should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy Adjunctive therapy should be used as clinically indicated Where Pseudomonas aeruginosa is a documented or presumptive pathogen, combination therapy with an anti-pseudomonal β-lactam is recommended [see Clinical Studies (14.1)].

Empiric treatment with levofloxacin may be initiated before culture and susceptibility results are known.

• Key considerations for empiric treatment include:
  • Local epidemiology and susceptibility patterns
  • Clinical indication for adjunctive therapy
  • Potential for Pseudomonas aeruginosa as a pathogen, which may require combination therapy with an anti-pseudomonal β-lactam 2 2

From the Research

Empiric Treatment

• Empiric treatment is a critical aspect of managing infections, especially in critically ill patients, as inadequate antibiotic therapy can lead to increased mortality and morbidity 3, 4.
• The selection of empiric therapy has become increasingly difficult due to the rising incidence of antibiotic-resistant bacteria, and it is essential to consider the likely etiologies and anticipated resistance patterns when choosing an empiric agent 3.
• Current diagnostic and treatment guidelines suggest that all seriously ill patients in whom infection is suspected undergo a comprehensive work-up to confirm the etiology prior to initiation of antibiotic therapy 3.
• Initial empiric broad-spectrum antibiotic therapy is necessary for the treatment of patients with serious infections, and clinicians may need to tailor antibiotic therapy based on the patient's initial response after the organism is confirmed, and susceptibility test results are available 3, 4.

Factors to Consider in Empiric Therapy

• The choice of empiric therapy should be guided by the most likely pathogens based on differential diagnosis, severity of the illness, suspected source of infection, patient-specific factors, and local antibiotic susceptibility patterns 5.
• Newer broad-spectrum antibiotics should be reserved for critically ill patients where there is a high likelihood of infection with a multidrug-resistant organism (MDRO) 5.
• The lack of rapid and sensitive culture techniques has made the selection of empiric therapy challenging, and it is crucial to consider local epidemiology when making decisions regarding empiric therapy 3, 6.

Antibiotic Options for Empiric Therapy

• Ceftriaxone is a third-generation cephalosporin with a broad spectrum of activity against Gram-positive and Gram-negative aerobic, and some anaerobic, bacteria, and has been effective in treating infections due to multidrug-resistant Enterobacteriaceae 7.
• Imipenem, cefepime, ceftazidime, and piperacillin/tazobactam are adequate choices for empiric therapy in secondary peritonitis, especially when Enterococcus is not targeted 6.
• Tigecycline is a viable monotherapeutic choice for empiric therapy in secondary peritonitis, especially when Enterococcus is included in the epidemiologic mix 6.