Antibiotic susceptibility patterns among Shigella sonnei, isolated during three different periods in Region Metropolitana, Chile

作者：Marcoleta Alicia; Toro Cecilia; Prado Valeria; Serrano Marcela; Fernandez Pilar; Benadof Dona; Camponovo Rossana; Campos Veronica; Porte Lorena; Zamorano Juanita; Ortega Camila; Urqueta Belen; Teresa Ulloa M

来源：Revista Chilena de Infectologia, 2013, 30(6): 616-621.

DOI：10.4067/S0716-10182013000600007

• Shigella
• shigellosis
• antimicrobial resistance
• multidrug resistance
• diarrhea

Background: Shigella sonnei gastroenteritis improves clinically and microbiologically with antibacterial treatment; however choosing a useful drug is a universal challenge because of in vitro susceptibility of S. sonnei frequently evolves to be resistant. Objective: To evaluate in vitro susceptibility of S. sonnei strains isolated from patients attending at the Chilean Region Metropolitana and to know the evolution that resistant patterns of S. sonnei have experienced. Material: In this study, the antimicrobial susceptibility profile of 277 isolates of Shigella sonnei was compared. The analyzed periods of time were: period I (1995-1997) 85 strains; period 11 (2004-2006) 92 strains and period 111 (2008-2009) 100 strains, in Santiago, Chile. The method performed to analyze susceptibility patterns was the disc diffusion (Kirby-Bauer). Results: The strains showed rates of resistance to ampicillin: period I, 85.8%; period II, 53.3%; period III, 100%, trimethoprim/sulfamethoxazole: period I, 50.5%; period, 11 46.7%; period III, 100%, chloramphenicol: period I, 36.4%; period II, 12%; period III, 100% and tetracycline: period I, 38.8%; period II, 30.4%; period III, 100%. 98.9% of the strains showed susceptibility to quinolones. Significant differences were observed in patterns of antimicrobial resistance for both individuals and for multidrug resistance (%26gt;= 3 antimicrobials) in the three periods (p %26lt;0.001, x(2) test). Of all resistant strains, 17% were resistant to 1 or 2 antibiotics, while 65.7% showed a pattern of multidrug resistance; 100% of the period III strains presented multidrug resistance. Conclusion: These results showed the temporal resistance dynamics of S. sonnei circulating strains in the Chilean Region Metropolitana. Due to the endemic behavior of shigellosis in Chile, it is urgent to maintain permanent surveillance of antimicrobial resistance profiles to improve both prevention and treatment of shigellosis.

• 出版日期2013-12