From the Guidelines
The initial treatment approach for most infectious diseases involves empiric antimicrobial therapy based on the most likely pathogens while awaiting definitive diagnostic results, as recommended by the Infectious Diseases Society of America in their 2019 guidelines 1. This approach typically begins with a broad-spectrum antibiotic such as amoxicillin-clavulanate (875/125 mg twice daily), ceftriaxone (1-2 g daily), or azithromycin (500 mg on day 1, then 250 mg daily for 4 days) depending on the suspected infection site and severity. Some key considerations for the initial treatment approach include:
- The need for empiric antimicrobial therapy to be guided by the most likely pathogens and the severity of the infection
- The importance of supportive care measures, including adequate hydration, fever management with acetaminophen (650 mg every 6 hours as needed), and rest
- The need to narrow therapy to the most appropriate targeted agent once culture results and antimicrobial susceptibility testing are available to reduce resistance development and side effects
- The duration of treatment varies by infection type, ranging from 3-5 days for uncomplicated urinary tract infections to 7-14 days for pneumonia or cellulitis, as noted in the 2007 guidelines from the Infectious Diseases Society of America and the American Thoracic Society 1. The 2011 guidelines from the Infectious Diseases Society of America also emphasize the importance of modifying the initial antibiotic regimen based on clinical and microbiologic data 1. Overall, the initial treatment approach for most infectious diseases should balance the need to rapidly control infection while practicing antimicrobial stewardship, as overuse of broad-spectrum antibiotics contributes to resistance development, disrupts normal flora, and increases risk of complications like Clostridioides difficile infection.
From the Research
Initial Treatment Approach for Infectious Diseases
The initial treatment approach for most infectious diseases involves the use of antimicrobial agents, such as antibiotics. The key considerations in selecting an initial antibiotic treatment include:
- Providing coverage for the causative pathogens 2
- Administering the antibiotics in a manner that ensures optimal drug delivery to the site of infection 2
- Utilizing treatment strategies that strive to deliver antibiotics in an individualized manner aimed at attaining desired pharmacokinetic/pharmacodynamic targets 2
Antibiotic Selection and Administration
The selection of an antibiotic depends on various factors, including the type of infection, the causative pathogen, and the patient's characteristics. Some antibiotics, such as ceftriaxone, have a broad spectrum of activity against Gram-positive and Gram-negative aerobic and anaerobic bacteria 3. The administration of antibiotics can be intravenous or intramuscular, and the dosing and duration of treatment depend on the specific infection and patient characteristics.
Duration of Antibiotic Treatment
Recent studies have shown that shorter durations of antibiotic treatment can be effective for many common infections, including community-acquired pneumonia, intraabdominal sepsis, and gram-negative bacteraemia 4. The goal of antibiotic treatment is to maximize the likelihood of curing the infection while minimizing the risk of antimicrobial resistance and adverse effects.
General Principles of Antimicrobial Therapy
The general principles of antimicrobial therapy include:
- Obtaining an accurate diagnosis of infection
- Understanding the difference between empiric and definitive therapy
- Identifying opportunities to switch to narrow-spectrum, cost-effective oral agents for the shortest duration necessary 5
- Recognizing the importance of antimicrobial stewardship and consulting infectious disease specialists for guidance when needed 5
Initial Antimicrobial Management of Sepsis
In cases of sepsis, immediate, empiric, broad-spectrum therapy is necessary to reduce mortality, but this approach should be accompanied by a commitment to de-escalation and antimicrobial stewardship 6. Biomarkers such as procalcitonin can provide decision support for antibiotic use and guide duration of antibiotic therapy 6.