Treatment of Cellulitis in Saphenous Vein Graft Leg After CABG
For cellulitis in the saphenous vein donor leg after coronary artery bypass grafting, treat with a β-lactam antibiotic (cephalexin 500 mg PO QID or dicloxacillin 500 mg PO QID) for 5 days, elevate the leg, and aggressively treat any underlying tinea pedis or toe web abnormalities to prevent recurrence. 1
Initial Antibiotic Selection
First-line therapy should be a penicillinase-resistant penicillin (dicloxacillin) or first-generation cephalosporin (cephalexin) targeting β-hemolytic streptococci and methicillin-sensitive Staphylococcus aureus, which are the predominant pathogens in post-CABG saphenous donor leg cellulitis 1, 2
The clinical presentation in these patients is typically dramatic with high fever (>38.8°C), chills, systemic toxicity, and obvious cellulitis, often with lymphangitis, strongly suggesting group A streptococcal infection 2, 3
MRSA coverage is NOT routinely needed for typical cellulitis in this population unless specific risk factors are present (purulent drainage, penetrating trauma, known MRSA colonization, or failure of β-lactam therapy) 1, 4
Treatment Duration
5 days of antibiotic therapy is sufficient if clinical improvement occurs, with extension only if the infection has not improved within this timeframe 1
This shorter duration (5 days) is as effective as traditional 10-day courses for uncomplicated cellulitis 5
Critical Adjunctive Measures
Elevation of the affected leg is essential to promote gravity drainage of edema and inflammatory substances, which hastens improvement 1
Address Predisposing Factors Immediately:
Examine interdigital toe spaces carefully for tinea pedis (scaling, fissuring, maceration), as superficial fungal infection is strongly associated with recurrent cellulitis in saphenous donor legs 1, 3
In two documented cases, controlling dermatophytosis stopped recurrent attacks entirely 3
Treat any venous insufficiency, lymphedema, or toe web abnormalities aggressively 1
When to Hospitalize
Admit patients if they exhibit:
- Systemic inflammatory response syndrome (SIRS) criteria 1
- Hemodynamic instability 1
- Altered mental status 1
- Failure of outpatient therapy 1
- Concern for deeper or necrotizing infection 1
Prevention of Recurrence
This is a well-documented complication specific to saphenous vein harvest sites, with some patients experiencing 20+ episodes 2, 3
For patients with 3-4 episodes per year despite treating predisposing factors:
- Consider prophylactic oral penicillin or erythromycin BID for 4-52 weeks 1
- Alternative: intramuscular benzathine penicillin every 2-4 weeks 1
- Continue prophylaxis as long as predisposing factors (lymphatic compromise, tinea pedis) persist 1
Common Pitfalls to Avoid
Do not add routine MRSA coverage without specific risk factors—this is typical streptococcal cellulitis 1, 4
Do not overlook tinea pedis examination—the fungal-bacterial interaction is central to the pathogenesis in post-CABG patients 3
Do not treat for only 3 days—minimum 5 days is required even with rapid improvement 1
Do not forget leg elevation—this simple measure significantly accelerates resolution 1
Special Consideration for Penicillin Allergy
If severe penicillin allergy exists, use clindamycin monotherapy (covers both streptococci and S. aureus), as 99.5% of S. pyogenes strains remain susceptible 5