From the Guidelines
Cellulitis in diabetic patients should be treated with antibiotics that cover common skin pathogens, with consideration of the increased risk of resistant organisms, and 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.
Key Considerations
- Diabetic patients are at higher risk for complications including deeper tissue infections, osteomyelitis, and poor wound healing due to impaired microcirculation, neuropathy, and immune dysfunction.
- First-line treatment typically involves antibiotics active against streptococci, such as cephalexin or dicloxacillin, for mild to moderate infections.
- For more severe infections or patients with risk factors for MRSA, consider broader-spectrum antibiotics like clindamycin or trimethoprim-sulfamethoxazole.
- In severe cases requiring hospitalization, intravenous options include vancomycin, ceftriaxone, or piperacillin-tazobactam.
- Elevation of the affected limb, proper wound care if applicable, and assessment for deeper tissue involvement are essential components of management.
- Treatment should be reassessed after 48-72 hours, and if improvement is not seen, consider broadening antibiotic coverage or investigating for deeper infection or osteomyelitis 1.
Management Strategies
- Close monitoring of blood glucose levels during infection as cellulitis can worsen glycemic control.
- Consideration of underlying conditions that may have predisposed to the infection, such as tinea pedis or venous eczema.
- Measures to reduce recurrences of cellulitis include treating interdigital maceration and keeping the skin well hydrated with emollients.
- Prophylactic antibiotics may be considered for patients with frequent infections, but published results demonstrating efficacy have been mixed 1.
From the FDA Drug Label
Adult diabetic patients with clinically documented complicated skin and skin structure infections ("diabetic foot infections") were enrolled in a randomized (2:1 ratio), multi-center, open-label trial comparing study medications administered IV or orally for a total of 14 to 28 days of treatment One group of patients received ZYVOX 600 mg q12h IV or orally; the other group received ampicillin/sulbactam 1. 5 to 3 g IV or amoxicillin/clavulanate 500 to 875 mg every 8 to 12 hours (q8–12h) orally. The cure rates in the clinically evaluable patients (excluding those with indeterminate and missing outcomes) were 83% (159/192) and 73% (74/101) in the linezolid- and comparator-treated patients, respectively A critical post-hoc analysis focused on 121 linezolid-treated and 60 comparator-treated patients who had a Gram-positive pathogen isolated from the site of infection or from blood, who had less evidence of underlying osteomyelitis than the overall study population, and who did not receive prohibited antimicrobials Based upon that analysis, the cure rates were 71% (86/121) in the linezolid-treated patients and 63% (38/60) in the comparator-treated patients.
Cellulitis treatment in diabetics: The cure rates for linezolid-treated patients with diabetic foot infections were 83% in clinically evaluable patients and 71% in a critical post-hoc analysis of patients with Gram-positive pathogens.
- Key pathogens:
- Staphylococcus aureus: 78% cure rate
- Methicillin-resistant S aureus: 71% cure rate
- Streptococcus agalactiae: 86% cure rate 2
From the Research
Cellulitis Treatment in Diabetics
- Cellulitis is a bacterial skin and soft tissue infection that occurs when the physical skin barrier, the immune system, and/or the circulatory system are impaired 3.
- Diabetes is a major predisposing factor for cellulitis due to defects in these areas 3.
- The treatment of cellulitis typically involves empiric antibiotic choices, with novel antimicrobial agents available for registration 3.
Antibiotic Treatment
- The majority of non-purulent, uncomplicated cases of cellulitis are caused by β-hemolytic streptococci or methicillin-sensitive Staphylococcus aureus, and can be treated with oral antibiotics such as penicillin, amoxicillin, and cephalexin 4.
- Broad-spectrum antibiotic use in uncomplicated cellulitis is common but often unjustified, and implementation of clinical practice guidelines can help limit their use 5.
- A study found that recovery from cellulitis is not associated with the route of antibiotic administration, and that a course length of > 5 days does not result in additional benefit 6.
Evidence-Based Care Pathways
- The use of evidence-based care pathways for cellulitis can improve process, clinical, and cost outcomes, including reducing broad-spectrum antibiotic use and pharmacy costs 7.
- These pathways can be embedded into electronic medical records and accompanied by education for physicians to ensure consistent and effective care 7.