What are the empiric antibiotics for skin and soft tissue infections?

From the Guidelines

For skin and soft tissue infections, empiric antibiotic therapy should be guided by the severity and type of infection, with oral options including clindamycin, trimethoprim-sulfamethoxazole, or a tetracycline for mild to moderate uncomplicated infections, as recommended by the Infectious Diseases Society of America 1. When considering empiric antibiotic therapy for skin and soft tissue infections, it is crucial to assess the severity and type of infection to guide the choice of antibiotic.

• For outpatients with purulent cellulitis, empirical therapy for CA-MRSA is recommended pending culture results, with options including clindamycin, trimethoprim-sulfamethoxazole, or a tetracycline 1.
• For outpatients with nonpurulent cellulitis, empirical therapy for infection due to b-hemolytic streptococci is recommended, with options including clindamycin alone or in combination with a b-lactam antibiotic 1.
• For hospitalized patients with complicated skin and soft tissue infections, empirical therapy for MRSA should be considered pending culture data, with options including intravenous vancomycin, linezolid, or daptomycin 1. It is essential to note that incision and drainage is the primary treatment for cutaneous abscesses, and antibiotic therapy should be considered in addition to incision and drainage for severe or extensive disease, or when there are signs of systemic illness or associated comorbidities 1.
• The treatment duration should be individualized based on the patient's clinical response, with a recommended duration of 5-10 days for uncomplicated infections and 7-14 days for complicated infections 1.
• Clinical improvement should be evident within 48-72 hours, and if not, reassessment and broadening of antibiotic coverage may be necessary 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 A modified intent-to-treat (MITT) analysis of 316 linezolid-treated patients and 313 oxacillin-treated patients included subjects who met all criteria for study entry. The cure rates in the MITT analysis were 86% in linezolid-treated patients and 82% 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 PathogenCured ZYVOXn/N (%)Oxacillin/Dicloxacillinn/N (%) Staphylococcus aureus73/83 (88)72/84 (86) Methicillin-resistant S aureus2/3 (67)0/0 (-) Streptococcus agalactiae6/6 (100)3/6 (50) Streptococcus pyogenes18/26 (69)21/28 (75)

Empiric Antibiotics for Skin and Soft Tissue Infections:

• Linezolid is effective against various pathogens, including Staphylococcus aureus and Streptococcus species.
• The cure rates for linezolid-treated patients were 90% in clinically evaluable patients and 86% in the MITT analysis.
• Oxacillin/Dicloxacillin is also effective, with cure rates of 85% in clinically evaluable patients and 82% in the MITT analysis.
• Methicillin-resistant S aureus had a cure rate of 67% with linezolid treatment.
• The choice of empiric antibiotic should be based on the suspected or confirmed pathogen and local resistance patterns 2.

From the Research

Empiric Antibiotics for Skin Soft Tissue Infections

• The choice of empiric antibiotics for skin soft tissue infections should cover methicillin-resistant Staphylococcus aureus (MRSA) as it is a common cause of purulent skin and soft tissue infections 3.
• Bacterial wound cultures are important for characterizing local susceptibility patterns and guiding definitive antibiotic therapy 3.
• The duration of antibiotic therapy is typically 5 to 7 days, although this may vary depending on the severity of the infection and local susceptibility patterns 3.

Avoidable Antibiotic Exposure

• Avoidable antibiotic exposure, defined as the use of broad-spectrum antibiotics, combination therapy, or treatment for 10 or more days, occurs in approximately 46% of cases of uncomplicated skin and soft tissue infections 4.
• The use of short-course, single-antibiotic treatment strategies could reduce prescribed antibiotic-days by 19% to 55% 4.
• Inappropriate broad-spectrum antibiotic selection is commonly used for uncomplicated skin and soft tissue infections, representing a significant opportunity for antimicrobial stewardship 5.

Treatment Outcomes

• The high rate of successful treatment among children with uncomplicated community-acquired MRSA skin and soft tissue infections, even when given inappropriate antibiotic therapy, suggests that treatment of these infections without appropriate antibiotic therapy is possible 6.
• Incision and drainage may play an important role in the treatment of uncomplicated skin and soft tissue infections 6.
• Successful treatment of MRSA infections remains challenging and requires the evaluation of both novel antimicrobials and adjunctive aspects of care, such as infectious disease consultation, echocardiography, and source control 7.