What is the treatment for cellulitis caused by a scratch?

From the Guidelines

For cellulitis from a scratch, the most effective treatment is a 5- to 6-day course of antibiotics active against streptococci, such as cephalexin, dicloxacillin, or clindamycin, as recommended by the American College of Physicians 1.

Key Considerations

• The choice of antibiotic should be based on the severity of the infection and the patient's ability to self-monitor and follow up with primary care.
• Patients with penetrating trauma, evidence of MRSA infection, nasal colonization with MRSA, injection drug use, or systemic inflammatory response syndrome may require additional antimicrobial coverage against MRSA.
• Elevation of the affected area, cleaning the wound with mild soap and water, and applying an over-the-counter antibiotic ointment can help promote healing and reduce the risk of complications.

Treatment Options

• Cephalexin (500mg four times daily) for 5-6 days
• Dicloxacillin (500mg four times daily) for 5-6 days
• Clindamycin (300-450mg three times daily) for 5-6 days

Important Notes

• Cellulitis can be a serious infection that requires prompt medical attention, especially if symptoms worsen or do not improve with treatment.
• Patients should be educated on how to recognize signs of worsening infection, such as increasing redness, warmth, swelling, or fever, and seek immediate medical attention if these symptoms occur.
• The 2014 IDSA guideline recommends that patients with uncomplicated cellulitis should receive antibiotics for 5 days, but treatment should be extended if the infection has not improved within this time period 1. However, the most recent guideline from the American College of Physicians recommends a 5- to 6-day course of antibiotics 1.

From the FDA Drug Label

Skin and skin structure9/13 (69)5/5 (100) The cure rates in clinically evaluable patients were 90% in linezolid-treated patients and 85% in oxacillin-treated patients 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) Cellulitis from a scratch treatment can be treated with linezolid, with a cure rate of 90% in clinically evaluable patients, as shown in the study 2.

• The cure rates for skin and skin structure infections were 69% to 100%.
• The cure rates for Staphylococcus aureus were 88%.
• The cure rates for Methicillin-resistant S aureus were 67%.
• The cure rates for Streptococcus agalactiae were 100%.
• The cure rates for Streptococcus pyogenes were 69%.

From the Research

Treatment Options for Cellulitis from a Scratch

• The treatment of cellulitis, a common skin infection, often involves the use of antibiotics, with the choice of antibiotic depending on the suspected causative organism and local resistance patterns 3, 4, 5.
• For uncomplicated cellulitis, where community-acquired methicillin-resistant Staphylococcus aureus (MRSA) is infrequent, oxacillin or cefalotin may be considered as the drugs of choice 3.
• In areas with a high prevalence of community-associated MRSA infections, antibiotics with activity against MRSA, such as trimethoprim-sulfamethoxazole and clindamycin, may be preferred for empiric therapy 4, 5.
• A systematic review and meta-analysis found no evidence to support the superiority of any one antibiotic over another for the treatment of cellulitis, and the use of antibiotics with activity against MRSA did not add an advantage 6.

Antibiotic Choices

• Cephalexin, trimethoprim-sulfamethoxazole, and clindamycin are commonly prescribed antibiotics for the treatment of cellulitis 4, 5.
• The choice of antibiotic should be based on the severity of the infection, the presence of MRSA, and the patient's individual characteristics, such as allergy history and renal function 4, 5.
• The duration of treatment and the route of administration (oral or intravenous) should be determined on a case-by-case basis, with no clear evidence to support one approach over another 6.

Considerations for Treatment

• The treatment of cellulitis should take into account the changing resistance profile of the causative organisms, particularly Staphylococcus aureus 3.
• The presence of MRSA should be considered when selecting an antibiotic, particularly in areas with a high prevalence of community-associated MRSA infections 4, 5.
• Further studies are needed to determine the most effective antibiotic regimens and treatment durations for cellulitis, as well as to develop standardized outcomes for evaluating treatment success 6.