Epidemiology and staphylococcal cassette chromosome mec typing of methicillin-resistant Staphylococcus aureus isolates in Taiwan: A multicenter study

• Published in: Journal of the Formosan Medical Association 2014-07, Vol.113 (7), p.409-416
• Main Authors: Pan, Sung-Ching, Wang, Jann-Tay, Lauderdale, Tsai-Ling, Ko, Wen-Chien, Chen, Yao-Shen, Liu, Jien-Wei, Lau, Yeu-Jun, Wang, Li-Hsin, Liu, Ke-Sun, Liao, Chun-Hsing, Lin, San-Yi, Hu, Bor-Shen, Chang, Shan-Chwen
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents - pharmacology; Anti-Bacterial Agents - therapeutic use; Chromosomes, Bacterial; Community-Acquired Infections - epidemiology; Community-Acquired Infections - microbiology; Cross Infection - epidemiology; Cross Infection - microbiology; Female; Humans; Internal Medicine; Male; methicillin resistance; Methicillin-Resistant Staphylococcus aureus - drug effects; Methicillin-Resistant Staphylococcus aureus - genetics; Microbial Sensitivity Tests; Middle Aged; Molecular Typing; Retrospective Studies; staphylococcal infections; Staphylococcal Infections - drug therapy; Staphylococcal Infections - epidemiology; Staphylococcal Infections - microbiology; Staphylococcus aureus; Taiwan - epidemiology
• ISSN: 0929-6646
• DOI: 10.1016/j.jfma.2012.05.012

Background/Purpose After community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) was identified, new community-onset, healthcare-associated MRSA (HA-MRSA-CO) infections have been noticed as MRSA infection in patients with community-onset infection who have underlying conditions resulting in frequent exposure to the healthcare system. However, previous studies have not thoroughly investigated whether HA-MRSA-CO has characteristics resembling those of CA-MRSA or hospital-onset, healthcare-associated MRSA (HA-MRSA-HO) infection. Methods A multicenter, retrospective study was conducted to analyze the clinical and microbiological data of patients with clinical isolates of MRSA from nine hospitals in Taiwan. Results In total, 203 patients with MRSA isolates, including 27 patients with CA-MRSA (13.3%), 59 with HA-MRSA-CO (29.1%), and 117 with HA-MRSA-HO (57.6%), were studied. Compared to HA-MRSA-HO isolates, the CA-MRSA and HA-MRSA-CO isolates were associated with a higher proportion of skin and soft tissue infections (81.8% and 65.3% vs. 40.5%, p = 0.001 and p = 0.002) as well as lesser rate of resistance to ciprofloxacin (33.3% and 50.9% vs. 74.4%, p < 0.001 and p = 0.002), gentamicin (44.4% and 64.4% vs. 84.6%, p < 0.001 and p = 0.002), and trimethoprim/sulfamethoxazole (33.3% and 42.4% vs. 58.1%, p = 0.02 and p = 0.048), and a lower 30-day all-cause mortality rate (7.4% and 0% vs. 20.9%, p < 0.001). Most of the CA-MRSA isolates were classified as staphylococcal cassette chromosome mec (SCC mec ) type VT (11/27, 40.7%), whereas most HA-MRSA-HO isolates were classified as SCC mec type III (66/117, 56.4%). Conclusion The CA-MRSA, HA-MRSA-CO, and HA-MRSA-HO clinical isolates significantly differed in their clinical presentations and molecular characteristics.