Abstract: To investigate the trends of antibiotic resistance in strains of Shigella isolated in Beijing, the susceptibility of 30 antimicrobial agents was observed in 327 Shigella strains isolated from 1994 to 2001. The resistance rates of fluoroquinolones increased gradually over the eight years, and the resistance rates of norfloxacin and ciprofloxacin (11.6% and 16.3% respectively) during 1997-1998 were significantly higher than that in 1994 (P<0.001). Meanwhile intermediately susceptible strains of fluoroquinolones also increased gradually from 1994 to 1998,and increased rapidly during 1999-2001, which suggests that the resistance rate of fluoroquinolones may increase rapidly in the coming years. In addition there was partial cross-resistance among fluoroquinolones, and the rate of resistance to 5 species of fluoroquinolones had been increasing from 1995 to 2001. It increased to 8.5% during 1999-2001. The resistance rates of Aminoglycoside and the first-generation cephalosporins remained relatively stable over the eight years, which can be used as the first-line agents for the treatment of dysentery, but intermediately susceptible strains of amikacin and almost all of cephalosporins have increased, which should be noticed.

Key words: Shigella, Shigella, Resistance, Resistance