What is the first-line treatment for skin and soft tissue infections?

From the Guidelines

The first-line treatment for skin and soft tissue infections is typically an antibiotic regimen based on the severity and type of infection, with a recommended course of 5 to 6 days for nonpurulent cellulitis, as suggested by the American College of Physicians 1. For uncomplicated skin infections like cellulitis or impetigo, oral antibiotics such as cephalexin, dicloxacillin, or clindamycin are recommended. If methicillin-resistant Staphylococcus aureus (MRSA) is suspected, trimethoprim-sulfamethoxazole, doxycycline, or linezolid may be used. Some key points to consider in the treatment of skin and soft tissue infections include:

• The use of incision and drainage for abscesses, as recommended by the Infectious Diseases Society of America 1
• The consideration of local resistance patterns, patient allergies, and comorbidities when choosing an antibiotic
• The importance of proper wound care, including cleaning with soap and water, applying topical antibiotics for minor infections, and possibly incision and drainage for abscesses
• The potential need for hospitalization and intravenous antibiotics for more severe infections Some specific antibiotic regimens that may be used for skin and soft tissue infections include:
• Cephalexin (500 mg four times daily for 5-10 days)
• Dicloxacillin (500 mg four times daily for 5-10 days)
• Clindamycin (300-450 mg three times daily for 5-10 days)
• Trimethoprim-sulfamethoxazole (1-2 double-strength tablets twice daily)
• Doxycycline (100 mg twice daily)
• Linezolid (600 mg twice daily) It's worth noting that the choice of antibiotic should be based on the severity and type of infection, as well as the patient's individual needs and circumstances. In general, the treatment of skin and soft tissue infections should be guided by the principles of antimicrobial stewardship, with the goal of using the most effective and narrow-spectrum antibiotic possible, while minimizing the risk of adverse effects and promoting optimal patient outcomes. The most recent and highest quality study on this topic is from 2021, which provides guidance on the appropriate use of short-course antibiotics in common infections, including skin and soft tissue infections 1.

From the FDA Drug Label

The cure rates in clinically evaluable patients were 90% in linezolid-treated patients and 85% in oxacillin-treated patients The cure rates by pathogen for microbiologically evaluable patients are presented in Table 18. Table 18 Cure Rates at the Test-of-Cure Visit for Microbiologically Evaluable Adult Patients with Complicated Skin and Skin Structure Infections Pathogen Cured ZYVOX n/N (%) Oxacillin/Dicloxacillin n/N (%) Staphylococcus aureus 73/83 (88) 72/84 (86) Methicillin-resistant S aureus 2/3 (67) 0/0 (-) Streptococcus agalactiae 6/6 (100) 3/6 (50) Streptococcus pyogenes 18/26 (69) 21/28 (75)

The first-line treatment for skin and soft tissue infections is linezolid or oxacillin/dicloxacillin, with cure rates of 90% and 85%, respectively, in clinically evaluable patients 2.

• Key pathogens and their cure rates with linezolid are:
  • Staphylococcus aureus: 88%
  • Methicillin-resistant S aureus: 67%
  • Streptococcus agalactiae: 100%
  • Streptococcus pyogenes: 69%

From the Research

First-Line Treatment for Skin and Soft Tissue Infections

The first-line treatment for skin and soft tissue infections (SSTIs) depends on the severity and suspected causative pathogens of the infection.

• For moderate skin and soft tissue infections, oral antibiotics such as trimethoprim-sulfamethoxazole, clindamycin, doxycycline/minocycline, or linezolid may be used in the outpatient setting 3.
• In cases of community-acquired SSTIs, a first-generation cephalosporin or an antistaphylococcal penicillin is recommended as the first-line empirical therapy 4.
• For patients with penicillin allergy, clindamycin is preferred over macrolides due to the increasing prevalence of macrolide-resistant S. aureus and beta-haemolytic streptococci 4.
• Sulfamethoxazole-trimethoprim (SXT) is also a viable option for the treatment of SSTIs, including impetigo, cellulitis, and abscess, particularly when group A Streptococcus (GAS) or Staphylococcus aureus (including MRSA) is suspected 5.
• Vancomycin may be considered in cases where MRSA is highly suspected, but its use is associated with concerns such as increasing MICs and clinical failures 3.
• Alternative therapies like linezolid, daptomycin, ceftaroline, ceftobribole, dalbavancin, oritavancin, and tedizolid may be used in certain situations, such as severe or invasive infections 3.

Specific Considerations

• The choice of antibiotic should be guided by the severity of the infection, patient factors, and diagnostic procedure reports 4.
• Adequate debridement of devitalized tissues and drainage of abscesses and fluid collections are essential components of SSTI management, in addition to systemic antibacterial therapy 4.
• In cases of nosocomial complicated SSTIs, piperacillin/tazobactam with or without vancomycin is the preferred agent for empirical treatment, depending on local resistance statistics 4.
• The use of newer antimicrobial agents like carbapenems, oxazolidinones, and streptogramins should be reserved for life-threatening situations or when resistant pathogens are suspected 4.