Three-Year Surveillance of Community-AcquiredStaphylococcus aureus Infections in Children

• Published in: Clinical infectious diseases 2005-06, Vol.40 (12), p.1785-1791
• Main Authors: Kaplan, Sheldon L., Hulten, Kristina G., Gonzalez, Blanca E., Hammerman, Wendy A., Lamberth, Linda, Versalovic, James, Mason, Edward O.
• Format: Article
• Language: English
• ISSN: 1058-4838; 1537-6591
• DOI: 10.1086/430312

Background. Methicillin-resistantStaphylococcus aureus (MRSA) isolates are increasingly frequent causes of skin and soft-tissue infections or invasive infections in many communities. Methods. Prospective surveillance for community-acquiredS. aureus infections at Texas Children's Hospital was initiated on 1 August 2001. Infections meeting the definition of community-acquired were identified. Demographic and clinical data were collected. Antibiotic susceptibilities, including inducible resistance to macrolide, lincosamide, and streptogramin B (MLSB), were determined in the clinical microbiology laboratory with the methodology of the NCCLS. All data were entered into a computer database. Data were analyzed by χ2 tests. Results. From 1 August 2001 to 31 July 2004, the percentage of community-acquiredS. aureus isolates that were methicillin resistant increased from 71.5% (551 of 771 isolates) in year 1 to 76.4% (1193 of 1562 isolates) in year 3 (P = .008). The number of both community-acquired MRSA (CA-MSRA) isolates and community-acquired methicillin-susceptibleS. aureus (CA-MSSA) isolates increased yearly, but the rate of increase was greater for the CA-MRSA isolates. Among the CA-MRSA isolates, 2542 (95.6%) were obtained from children with skin and soft-tissue infections, and 117 (4.4%) were obtained from children with invasive infections. Overall, 62% of children with CA-MRSA isolates and 53% of children with CA-MSSA isolates were admitted to the hospital (P = .0001). The rate of clindamycin resistance increased significantly for both CA-MRSA isolates (P = .003) and CA-MSSA isolates (P = .00003) over the 3 years. MLSB inducible resistance was found in 27 (44%) of 62 clindamycin-resistant CA-MSSA isolates, compared with 6 (4.5%) of 132 clindamycin-resistant CA-MRSA isolates (P < .000001). Conclusions. CA-MRSA isolates account for an increasing percentage and number of infections at Texas Children's Hospital. Clindamycin resistance increased among community-acquiredS. aureus isolates. Community surveillance of community-acquiredS. aureus infections is critical to determine the appropriate empiric antibiotic treatment for either local or invasive infections.