What is the recommended treatment for bacterial infections?

Treatment of Bacterial Infections

For bacterial infections, amoxicillin-clavulanate is the recommended first-line treatment due to its broad-spectrum activity against common bacterial pathogens including beta-lactamase producing organisms. 1

General Treatment Principles

First-Line Therapy Options

• Amoxicillin-clavulanate: 875/125 mg twice daily or 500 mg three times daily for adults; 45 mg/6.4 mg/kg/day divided into two doses for children 1, 2
• Amoxicillin: 500 mg three times daily for adults; 45-90 mg/kg/day for children with susceptible infections 1
• Cephalosporins: Cefuroxime (500 mg twice daily), cefpodoxime, or cefdinir for those with penicillin allergies 1

For Moderate to Severe Infections

• High-dose amoxicillin-clavulanate: 2000/125 mg twice daily for adults; 90/6.4 mg/kg/day in two divided doses for children 3, 4
• For hospitalized patients: Vancomycin plus antipseudomonal antibiotics (cefepime, carbapenem, or piperacillin-tazobactam) 1

For Penicillin-Allergic Patients

• Clindamycin: 300-450 mg every 6 hours for adults; 8-20 mg/kg/day divided into 3-4 doses for children 1, 5
• Fluoroquinolones (adults only): Levofloxacin 750 mg daily or moxifloxacin 400 mg daily 1
• Macrolides: Azithromycin 500 mg on day 1, then 250 mg daily for 4 days 1

Treatment Based on Infection Site

Skin and Soft Tissue Infections

• For impetigo or cellulitis: Dicloxacillin, cephalexin, or clindamycin 1
• For MRSA infections: Trimethoprim-sulfamethoxazole, doxycycline, or linezolid 1
• For animal bites: Amoxicillin-clavulanate (covers Pasteurella multocida and anaerobes) 1
• For human bites: Amoxicillin-clavulanate or ampicillin-sulbactam (covers Eikenella corrodens) 1

Respiratory Tract Infections

• Community-acquired pneumonia in adults: Amoxicillin 1.5-4 g/day or respiratory fluoroquinolone 1
• Pediatric pneumonia: Amoxicillin 80-100 mg/kg/day in three doses for children under 3 years; macrolides for children over 3 years 1
• Acute bacterial rhinosinusitis: Amoxicillin-clavulanate or high-dose amoxicillin 1

Intra-abdominal Infections

• Mild to moderate: Ampicillin-sulbactam, ticarcillin-clavulanate, or ertapenem 1
• Severe: Piperacillin-tazobactam, imipenem-cilastatin, or meropenem 1

Special Considerations

Duration of Therapy

• Most uncomplicated bacterial infections: 5-7 days 1
• Complicated skin and soft tissue infections: 7-14 days 1
• Streptococcal infections: At least 10 days to prevent rheumatic fever 5

Monitoring and Follow-up

• Assess clinical response within 48-72 hours of starting therapy 1
• If no improvement after 72 hours, consider changing antibiotics or reevaluating diagnosis 1
• Complete the full course of antibiotics even if symptoms improve quickly 2

Resistance Concerns

• Recent antibiotic use increases risk of resistant pathogens 1
• Consider local resistance patterns when selecting therapy 1
• For suspected resistant organisms, obtain cultures when possible before starting antibiotics 1

Specific Bacterial Pathogens

Streptococcus pneumoniae

• First-line: High-dose amoxicillin or amoxicillin-clavulanate 3
• For penicillin-resistant strains: Respiratory fluoroquinolones or high-dose amoxicillin-clavulanate 1, 4

Staphylococcus aureus

• Methicillin-susceptible: Dicloxacillin, cefazolin, or clindamycin 1
• MRSA: Vancomycin, linezolid, clindamycin, or trimethoprim-sulfamethoxazole 1

Haemophilus influenzae

• Beta-lactamase negative: Amoxicillin 1
• Beta-lactamase positive: Amoxicillin-clavulanate, cefuroxime, or fluoroquinolones 1, 4

Anaerobic Infections

• Metronidazole (500 mg three times daily) for pure anaerobic infections 1
• Amoxicillin-clavulanate, clindamycin, or moxifloxacin for mixed aerobic/anaerobic infections 1

Common Pitfalls to Avoid

• Not completing the full course of antibiotics, which may lead to treatment failure and antimicrobial resistance 2
• Using antibiotics for viral infections, which contributes to resistance development 2
• Underdosing antibiotics, particularly in pediatric patients or for resistant organisms 4
• Not considering local resistance patterns when selecting empiric therapy 1
• Failing to adjust therapy based on culture results when available 1

Remember that appropriate antibiotic selection, dosing, and duration are critical for successful treatment of bacterial infections while minimizing the risk of antimicrobial resistance.