What is the recommended treatment and management plan for a patient with cellulitis?

From the Guidelines

The recommended treatment for cellulitis typically involves antibiotics targeting common causative organisms like Streptococcus and Staphylococcus, with a 5-day course of antimicrobial therapy being as effective as a 10-day course if clinical improvement has occurred by 5 days 1.

Assessment

When assessing a patient with cellulitis, it is essential to consider the severity of the infection, the presence of systemic symptoms, and any underlying conditions that may have predisposed the patient to the infection. The patient's medical history, including any previous episodes of cellulitis, should be taken into account. A thorough physical examination should be performed to evaluate the extent of the infection and to check for any signs of complications.

Plan

The management plan for a patient with cellulitis should include:

• Antibiotic therapy: oral antibiotics such as cephalexin (500 mg four times daily), dicloxacillin (500 mg four times daily), or clindamycin (300-450 mg three times daily) for 5 days are appropriate for mild cases 1.
• Elevation of the affected limb to reduce swelling
• Pain control with acetaminophen or NSAIDs
• Proper wound care if applicable
• Monitoring of the patient's condition, including marking the border of the erythema to track progression or improvement
• Adequate hydration and rest
• Consideration of underlying conditions that may have predisposed the patient to the infection, such as tinea pedis or venous eczema
• For patients with severe infections or those with systemic symptoms, intravenous antibiotics may be necessary, including cefazolin (1-2 g every 8 hours), nafcillin (1-2 g every 4-6 hours), or vancomycin (15-20 mg/kg every 12 hours) if MRSA is suspected 1. Some key points to consider when managing cellulitis include:
• The importance of treating any underlying conditions that may have predisposed the patient to the infection
• The need for adequate hydration and rest
• The potential for complications, such as abscesses or sepsis, and the need for close monitoring
• The importance of marking the border of the erythema to track progression or improvement
• The potential for antibiotic resistance and the need for reassessment and possibly broader antibiotic coverage if the patient does not respond to initial treatment.

It is also important to note that elevation of the affected area hastens improvement by promoting gravity drainage of edema and inflammatory substances 1, and that patients should receive therapy for any predisposing conditions, such as tinea pedis, trauma, or venous eczema 1.

In terms of specific antibiotic regimens, a large percentage of patients can receive oral medications from the start for typical cellulitis, and suitable antibiotics for most patients include penicillin, amoxicillin, amoxicillin-clavulanate, dicloxacillin, cephalexin, or clindamycin 1.

Overall, the management of cellulitis requires a comprehensive approach that takes into account the severity of the infection, the presence of systemic symptoms, and any underlying conditions that may have predisposed the patient to the infection. The recommended duration of antimicrobial therapy is 5 days, but treatment should be extended if the infection has not improved within this time period 1.

From the FDA Drug Label

The cure rates in clinically evaluable patients with complicated skin and skin structure infections 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. The recommended treatment and management plan for a patient with cellulitis includes:

• Linezolid 600 mg IV or oral every 12 hours for 10 to 14 days, as described in the dosage guidelines for ZYVOX 2
• Monitoring of complete blood counts weekly, particularly in patients who receive linezolid for longer than two weeks, those with pre-existing myelosuppression, those receiving concomitant drugs that produce bone marrow suppression, or those with a chronic infection who have received previous or concomitant antibiotic therapy 2
• Consideration of discontinuation of therapy with linezolid in patients who develop or have worsening myelosuppression 2
• Initiation of specific Gram-negative therapy immediately if a concomitant Gram-negative pathogen is documented or suspected 2
• Monitoring for Clostridium difficile associated diarrhea (CDAD), which has been reported with use of nearly all antibacterial agents, including ZYVOX 2

From the Research

Assessment of Cellulitis

• The diagnosis of cellulitis is based primarily on history and physical examination, as there are no effective diagnostic modalities and many clinical conditions appear similar 3.
• Cellulitis is an infection of the deep dermis and subcutaneous tissue, presenting with expanding erythema, warmth, tenderness, and swelling 3.
• The majority of cases of cellulitis are nonculturable and therefore the causative bacteria are unknown, but in the 15% of cellulitis cases in which organisms are identified, most are due to β-hemolytic Streptococcus and Staphylococcus aureus 3.

Treatment and Management Plan

• Treatment of primary and recurrent cellulitis should initially cover Streptococcus and methicillin-sensitive S. aureus, with expansion for methicillin-resistant S. aureus (MRSA) in cases of cellulitis associated with specific risk factors 3.
• Five days of treatment is sufficient with extension if symptoms are not improved 3.
• The addition of an oral anti-inflammatory agent to antibiotic treatment can significantly shorten the time to regression of inflammation and complete resolution of cellulitis 4.
• Antibiotics with activity against community-associated MRSA, such as trimethoprim-sulfamethoxazole and clindamycin, are preferred empiric therapy for outpatients with cellulitis in the community-associated MRSA-prevalent setting 5.
• High-dose cephalexin may have fewer treatment failures but with a higher proportion of minor adverse effects compared to standard-dose cephalexin 6.

Factors to Consider

• Addressing predisposing factors can minimize the risk of recurrence 3.
• Failure to improve with appropriate first-line antibiotics should prompt consideration for resistant organisms, secondary conditions that mimic cellulitis, or underlying complicating conditions such as immunosuppression, chronic liver disease, or chronic kidney disease 3.
• The severity of cellulitis and therapy with an antibiotic that is not active against community-associated MRSA are factors associated with treatment failure 5.