Background: The permanent surveillance of antimicrobial susceptibility of Shigella sp in the Temuco Regional Hospital, allowed us to define the empirical use of antimicrobials in dysenteric syndrome.
Aim: To study antimicrobial susceptibility of Shigella strains collected from 1997 to May 2001 and compare the results with those reported in 1990.
Material and methods: Two hundred and seventeen Shigella strains, coming from stool cultures of pediatric patients, were studied.
Results: In the period 1989-1990 Shigella flexneri was the main species isolated (83%) whereas, in the period 1997-2001, Shigella sonnei (55.8%) predominated. In the second period, an increase of antimicrobial resistance, as compared with the period 1989-1990, was observed for ampicillin (74.5 and 42% respectively), for cotrimoxazol (57.5 and 45% respectively) and tetracycline (64 and 8% respectively). Chloramphenicol resistance increased from 0 to 57.5%. In the second period no resistance to ciprofloxacin was detected. There was simultaneous resistance to four drugs in 30% of the strains, predominating multiresistance in S flexneri (52.1%).
Conclusions: In the two periods studied, a significant increase was detected in the resistance of Shigella strains to antimicrobials.