Cephalexin plus trimethoprim-sulfamethoxazole was not superior to cephalexin alone for the treatment of outpatient non-purulent cellulitis.

Commentary on:  Moran GJ, Krishnadasan A, Mower WR, et al . Effect of cephalexin plus trimethoprim-sulfamethoxazole vs cephalexin alone on clinical cure of uncomplicated cellulitis: a randomised clinical trial. JAMA 2017;317:2088–96. Skin infections are one of the most common infections in ambulatory medicine. Yet, despite the high incidence of these infections, there remain questions about optimal treatment of cellulitis without abscess. Cellulitis without abscess is particularly challenging, as the aetiology of this infection remains relatively elusive. Studies employing molecular diagnostic techniques for bacteria from needle biopsies of cellulitis have failed to determine the aetiology of cellulitis without abscess. Current thinking is that cellulitis is usually caused by Group A Streptococcus and occasionally Staphylococcus aureus , possibly including methicillin-resistant S. aureus (MRSA). However, the relative contribution of these pathogens is unclear and the need to include anti-MRSA therapy as part of treatment for …