ABSTRACT
Suppurative methicillin-resistant Staphylococcus aureus (MRSA) skin infections are common and associated with MRSA colonization, but little is known about non-suppurative cellulitis and its relationship with MRSA colonization in areas endemic for community-associated MRSA. We prospectively enrolled patients hospitalized for non-suppurative cellulitis (n=50) and matched controls (n=100) and found S. aureus colonization was similar in cases and controls (30% vs. 25%, P=0·95). MRSA was uncommon in cases (6%) and controls (3%) (P=0·39). All MRSA isolates were USA300 by pulsed-field gel electrophoresis. Independent risk factors for non-suppurative cellulitis were diabetes (OR 3·5, 95% CI 1·4-8·9, P=0·01) and homelessness in the previous year (OR 6·4, 95% CI 1·9-20·9, P=0·002). These findings suggest that MRSA may only rarely be causative of non-suppurative cellulitis.
Subject(s)
Carrier State/epidemiology , Cellulitis/epidemiology , Community-Acquired Infections/epidemiology , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Staphylococcal Skin Infections/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Bacterial Typing Techniques , Carrier State/microbiology , Case-Control Studies , Cellulitis/microbiology , Child , Child, Preschool , Community-Acquired Infections/microbiology , Diabetes Complications , Electrophoresis, Gel, Pulsed-Field , Female , Humans , Male , Methicillin-Resistant Staphylococcus aureus/classification , Methicillin-Resistant Staphylococcus aureus/genetics , Middle Aged , Molecular Typing , Prospective Studies , Risk Factors , Staphylococcal Skin Infections/microbiology , Young AdultABSTRACT
We utilized Medline to perform a systematic review of the literature to quantify the aetiology of cellulitis with intact skin. Of 808 patients with cellulitis, 127-129 (15.7-16.0%) patients had positive needle aspiration and/or punch biopsy cultures from intact skin. Of the patients with positive cultures, 65 (50.4-51.2%) had cultures positive for Staphylococcus aureus, 35 (27.1-27.6%) for group A streptococcus, and 35-37 (27.1-29.1%) for other pathogens. The most common aetiology of cellulitis with intact skin, when it can be determined, is S. aureus, outnumbering group A streptococcus by a ratio of nearly 2:1. Given the increasing incidence of community-associated methicillin-resistant S. aureus infections, our findings may have critical therapeutic implications.
