Community-acquired methicillin-resistant Staphylococcus aureus infections in South Texas children

Background. Community-acquired methicillin-resistant Staphylococcus aureus (CAMRSA) infections have increased dramatically from 1990 to 2000. Objectives. The objectives of this retrospective study were to report the f requency of CAMRSA isolates, to describe the spectrum of disease observed i n children infected with CAMRSA and to compare the antibiotic susceptibilit y patterns of community-acquired and nosocomial methicillin-resistant S. au reus (MRSA) infections. Methods. All cases of S. aureus including MRSA infe ctions were identified by a computer-assisted search of the Vitek system cu lture results from 1990 to 2000 and review of the minutes of Infection Cont rol Committee meetings. Results. MRSA was isolated from 147 children (77 boys; 2 weeks to 17 years) from October 1, 1990, to December 31, 2000. Seven cases of CAMRSA were ide ntified from 1990 to 1996, and 53 cases were identified from 1997 to 2000 w ith 35 cases occurring in 2000. Of the 128 children whose medical records w ere reviewed, 60 (47%) had CAMRSA infections. In 53 (88%) of these 60 child ren no risk factor for MRSA was identified. Soft tissue infections accounte d for 48 (91%) of the 53 cases of the CAMRSA in children without known risk factors. CAMRSA isolates from children without known risk factors were mor e susceptible to trimethoprim-sulfamethoxazole (98% vs. 82%; P < 0.005) and clindamycin (92% vs. 57%; P < 0.001) and less susceptible to tetracycline (54% vs. 95%; P < 0.001) than were nosocomial MRSA isolates. Conclusions. The emergence of CAMRSA as a cause of common infections may re quire a change in the initial selection of antibiotics to assure appropriat e coverage in critically ill children.