A multicentre collaborative study of the antimicrobial susceptibility of community-acquired, lower respiratory tract pathogens 1992-1993: The Alexander Project

Abstract

The Alexander Project is a unique, international, collaborative antimicrobial susceptibility surveillance study of bacterial pathogens causing community-acquired lower respiratory tract infection. Fifteen centres, ten in the European Union (EU) and five in the USA, each submitted up to 400 isolated per year for 2 years (1992 and 1993) to a central laboratory for re-identification and determination of MICs of 15 antimicrobials using the Sensititre microbroth incorporation technique. Of the total of 6385 isolates collected, Haemophilus influenzae (2718), Streptococcus pneumoniae (1856) and Moraxella catarrhalis (818) were the most frequently identified pathogens. Staphylococcus aureus (690). Haemophilus parainfluenzae (183) and Klebsiella pneumoniae (120) were identified less commonly. High-level penicillin resistance in S. pneumoniae (MIC > or = 2 mg/L) was found in 222 isolates, an overall prevalence of 12% which varied from < 1% in Germany, Italy, UK and two of the five USA centres, to 3.8-40.4% in the remainder, with the highest prevalence found in France and Spain. Intermediate penicillin resistance (MIC 0.12-1 mg/L) was identified in 228 isolates of S. pneumoniae, an overall prevalence of 12.3%, with individual centre prevalence varying widely (EU, 0-52.3%; USA, 0-20.9%) and not always following that of high-level resistance. Resistance to other, unrelated, antimicrobials, except notably the fluoroquinolones, was strongly associated with beta-lactam resistance. beta-lactamase production was detected in 492 isolates of H. influenzae, an overall prevalence of 18.1%. Rates of detection varied widely between centres from 1.4% in Weingarten, Germany in 1993 to 38.5% in Barcelona, Spain in 1992. In general, the prevalence of beta-lactamase production was higher and less variable in USA centres than in those of the EU. beta-Lactamase was detected consistently in the majority of isolates of M. catarrhalis with an overall prevalence of 81.7%. Virtually no other resistance phenotype was recognised in this species. Of the 690 collected, most isolates of S. aureus produced beta-lactamase with rates of detection varying from 52.2%-89.1%. Isolates from two centres, Genoa, Italy in 1992 and Paris, France in 1993, were associated with a high prevalence of methicillin-resistance (34.8% and 43.8%, respectively). Combined isolates of H. parainfluenzae and K. pneumoniae accounted for only 4.7% of the total collection. Although the current data are insufficient to allow analysis of trends in resistance, the study participants have continued to collect further isolates in 1994 and 1995 which will be reported in the future.

Development of a Disk Diffusion Method for Testing Moraxella catarrhalis Susceptibility Using Clinical and Laboratory Standards Institute Methods: a SENTRY Antimicrobial Surveillance Program Report

“…Where a significant proportion of results were off scale, or where the number of wild-type strains was low, CO WT values were estimated by visual inspection. Results were compared to those available on the European Committee for Antimicrobial Susceptibility Testing (EUCAST) website (http://www.srga.org/eucastwt/WT_EUCAST.htm) and also to visual estimates of CO WT from previous studies which provided data on MIC distributions (2,15,24).…”

Pulmonary thin-section CT findings in acuteMoraxella catarrhalispulmonary infection

“…M. catarrhalis is considered to be the third most common and most important cause of bronchopulmonary infections after Streptococcus pneumoniae and Haemophilus influenzae [6,7]. In the Alexander project in Europe and the US between 1992 and 1993, M. catarrhalis was identified in 13.5% of bacterial isolates [8].…”

Macrolide-Resistant Streptococcus pneumoniae in Canada during 1998–1999: Prevalence of mef (A) and erm (B) and Susceptibilities to Ketolides

“…However, emergence of erythromycin resistance (Ery-R) in Streptococcus pneumoniae is a growing concern because of the importance of this pathogen in infections of the respiratory tract (6,13,15,25). Although the prevalence of resistant strains varies geographically and temporally, antimicrobial resistance is widespread (6,9,10,26). Macrolide resistance in S. pneumoniae has increased during the 1990s to the extent that over 30% of clinical isolates are now resistant in some communities (2,3,21,23,27).…”

“…The prevalence of the MLS B and M-phenotypes varies both geographically and temporally (9,10,13,21 Ketolides are third-generation, semisynthetic macrolides derived from clarithromycin (12). These 14-membered antibiotics are made by the replacement of the cladinose at C-3 with a keto group (12).…”