Antimicrobial susceptibility of lower respiratory tract pathogens in Great Britain and Ireland 1999-2001 related to demographic and geographical factors: the BSAC Respiratory Resistance Surveillance Programme.
OBJECTIVE
The aim of this study was to assess the antimicrobial susceptibility of community-acquired lower respiratory pathogens in Great Britain and Ireland, and investigate its relationship with demographic and geographical factors using multiple logistic regression analysis.


METHODS
A total of 1328 isolates of Streptococcus pneumoniae, 1894 Haemophilus influenzae and 845 Moraxella catarrhalis were collected from lower respiratory clinical specimens (primarily sputum) by 20 laboratories in Great Britain (England, Wales and Scotland) and Ireland (Northern Ireland and Eire) between 1999 and 2001.


RESULTS
Of 1154 S. pneumoniae from Great Britain, 92-100% were susceptible to beta-lactams (only 0.2% having penicillin MICs > or =2 mg/L), 89% were susceptible to erythromycin, 93% susceptible to tetracycline, and 94-100% intermediate or susceptible to fluoroquinolones. Susceptibility to agents other than fluoroquinolones was less frequent in the 174 isolates from Ireland: beta-lactam susceptibility was 68-99% (3.4% having penicillin MICs > or =2 mg/L), erythromycin susceptibility was 78% and tetracycline susceptibility was 82%. In multivariate analysis, susceptibility in S. pneumoniae was associated with country and patient age, being most common overall in the 20-49 years age group. Of 1894 H. influenzae, 15% produced beta-lactamase and 79-100% were susceptible to beta-lactams other than cefaclor. Ninety-six per cent were intermediate and 1% susceptible to erythromycin, 97% susceptible to tetracycline, and 89% susceptible to trimethoprim. Only one isolate showed resistance to ciprofloxacin. H. influenzae from sputum were more likely to be susceptible than isolates from other sources. Of 845 M. catarrhalis, 92% produced beta-lactamase and 9% were susceptible to ampicillin, >99% were susceptible to co-amoxiclav, cefotaxime, erythromycin and fluoroquinolones.


CONCLUSIONS
Clinically relevant demographic factors predictive of susceptibility were country and patient age in S. pneumoniae, and specimen type (sputum/non-sputum) in H. influenzae. Susceptibility to most antimicrobials remains high in Ireland and very high in Great Britain.
Department of Medical Microbiology, North Bristol NHS Trust, Southmead Hospital, Bristol BS10 5NB, UK. rosy.reynolds@btinternet.com
Rosy
R
Reynolds
Jemma
J
Shackcloth
David
D
Felmingham
Alasdair
A
MacGowan
D000328:Adult; D000367:Age Factors; D000368:Aged; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D024901:Drug Resistance, Multiple, Bacterial; D005260:Female; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology / Q000382:microbiology; D006192:Haemophilus Infections / Q000453:epidemiology / Q000382:microbiology; D006193:Haemophilus influenzae / Q000187:drug effects; D006801:Humans; D007223:Infant; D007494:Ireland / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D001936:Moraxella catarrhalis / Q000187:drug effects; D011008:Pneumococcal Infections / Q000453:epidemiology / Q000382:microbiology; D011159:Population Surveillance; D012141:Respiratory Tract Infections / Q000453:epidemiology* / Q000382:microbiology*; D012737:Sex Factors; D013296:Streptococcus pneumoniae / Q000187:drug effects; D006113:United Kingdom / Q000453:epidemiology
D000900:Anti-Bacterial Agents