A longitudinal perspective on Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis resistance trends in Europe: from GLOBAL surveillance studies

Abstract number: P601

Sahm D., Brown N., Pillar C., Draghi D., Obot-Tucker M., Thornsberry C.

Objective:Streptococcus pneumoniae (SP), Haemophilus influenzae (HI), and Moraxella catarrhalis (MC) are three of the most common pathogens associated with community-acquired pneumonia (CAP). Changes in the prevalence of resistance (R) and multi-drug R (MDR) among these pathogens can become problematic for clinicians treating infections. R rates can vary according to regional distributions. The GLOBAL Surveillance (SUR) initiative is a longitudinal study that benchmarks antimicrobial R among respiratory pathogens (RPs).

Methods: SP, HI, and MC isolates taken from patient specimens were collected from 6 countries in Europe (EU): Belgium (Bel), France (Fr), Germany (Gr), Italy (It), Spain (Sp), and the United Kingdom (UK). The years (Y) of collection were 03–04 (04), 05–06 (06) and 07 (respectively) for SP (N: 3213; 1542; 755); HI (N: 3183; 1578; 860) and MC (N: 722; 379; 163). All isolates were centrally tested by broth microdilution and interpreted according to CLSI standards (M7-A7 M100-S17). Data were analysed according to b-lactamase (BL) status [positive (+) and (-)] for HI and MC; for SP analysis included penicillin (PEN) and MDR phenotypes [R to 2 drugs: PEN, cefuroxime, trimeth-sulfa, azithromycin (AZI), and tetracycline].

Results: Overall for SP, PEN-R (%) was 12.7 in 04, 12.8, in 06 and 11.8 in 07. The PEN-R rates (%) varied in 04, 05, and 07, respectively: Bel (7.4; no data; 6.8), Fr (32.9; 23.7; 19.4), Gr (3.5; 5.7; 1.3), It (6.8; 7.7; 21.2), Sp (25.4; 20.8; 7.9), and UK (2.2; 2.8; 3.9). The prevalence (%) of MDR-SP ranged from 3.4 (UK) to 44.2 (Bel) in 04, 4.3 (UK) to 33.2 (Fr) in 06, and 12.4 (UK) to 48.2 (It) in 07. >98% of MDR-SP were susceptible (S) to levofloxacin (LFX). For HI, BL + rates (%) varied by country from 8 (Bel) to 32.3 (Fr) in 04, 7.3 (Gr) to 23.4 (Fr) in 06, and 3 (It) to 18.9 (UK) in 07. Based on MIC90, LFX and ceftriaxone were the most active agents tested against HI, regardless of BL status with MIC90s of 0.015–0.03 mg/L all Y. For MC, overall BL + rates (%) increase by Y slightly: 96.4 (04), 96.6 (06), and 98.2 (07). Regardless of phenotype, LFX and AZI were the most potent agents against MC, based on MIC90s (0.06 mg/L).

Conclusion: LFX showed potent activity against the RPs studied. LFX was active among PEN-R and MDR-SP and BL +/- HI and MC. %S among SP, HI, and MC remained high all Y for LFX. Continued SUR is warranted to monitor any changes that may occur among agents used to treat CAP pathogens.