10th Survey of antimicrobial resistance in noninvasive clinical isolates of Streptococcus pneumoniae collected in Belgium during winter 2007-2008 Dixieme surveillance de la resistance aux antibiotiques dans des souches non invasives de Streptococcus pneumoniae collectionnees en Belgique pendant l'hiver 2007 a` 2008

Objectives. – The aim of the study was to evaluate the antibiotic resistance in noninvasive clinical isolates of Streptococcus pneumoniae collected in Belgium during winter 2008–2007. Method. – Four hundred and forty eight unduplicated isolates collected by 15 laboratories were tested by microdilution following CLSI. Results. – Insusceptibility rates (I + R) were as follows: penicillin G (PEN) 11.6% (4.0% R), ampicillin 11.4% (4.0% R), amoxicillin + /–clavulanic acid 0, cefaclor 10.3% (9.6% R), cefuroxime 9.2% (8.7% R), cefuroxime-axetil 8.7% (7.8% R), cefotaxime, ceftazidime and cefepime 2.0% (0% R), imipenem 2.5% (0% R), ciprofloxacin and ofloxacin 5.1% (0.4% R), levofloxacin 0.7% (0.4% R), moxifloxacin 0.4% (0.2% R), erythromycin (ERY) 29.7% (29.2% R), azithromycin 29.7% (28.8% R), telithromycin 0%, clindamycin 26.3% (25.4% R) and tetracycline (TET) 21.9% (16.5% R). From 2001 to 2008, a significant decrease in penicillininsusceptibility (21.0% to 11.6%), penicillin-resistance (9.7% to 4.0%) and ciprofloxacin-insusceptibility (11.2% to 5.1%) was found. Cross-resistance between penicillin and other betalactams in penicillininsusceptible isolates was incomplete: all these isolates remained fully susceptible to amoxicillin. Erythromycin-insusceptibility was significantly higher in children than in adults (43.9%/27.4%), while penicillin-insusceptibility significantly higher in Brussels than in the Flanders (22.9%/8.1%). The commonest resistance phenotype was ERY-TET (12.7%) followed by ERY (7.4%) and PEN-ERY-TET (5.8%). Capsular types 19 (25%), 14 (19.3%), 23 (15.4%) and 15 (13.5%) were the most important in penicillininsusceptible.