Activities of Telithromycin, Erythromycin, Fluoroquinolones, and Doxycycline against Campylobacter Strains Isolated from Finnish Subjects

Abstract

The in vitro susceptibilities of 478 Campylobacter jejuni and Campylobacter coli strains isolated from Finnish subjects during 2002 to 2004 were determined. Susceptibility to erythromycin remained high, and telithromycin did not offer any advantage over erythromycin. Reduced susceptibilities to fluoroquinolones and doxycycline were detected almost exclusively among isolates of foreign origin.Campylobacter jejuni and C. coli are the most frequent bacterial enteropathogens in many countries, such as Finland (14). Few data on the in vitro activity of telithromycin against campylobacters are available (6, 7). We wanted to compare the activity of telithromycin to that of erythromycin against a substantial number of domestically acquired C. jejuni and C. coli isolates. In addition, susceptibilities to doxycycline, ciprofloxacin, and moxifloxacin were tested. Isolates of foreign origin selected on the basis of presumed resistance to erythromycin and/or ciprofloxacin were also included.A total of 393 human stool culture isolates (379 C. jejuni and 14 C. coli isolates) of domestic origin (patients had not been abroad within 2 weeks prior to becoming ill) were collected in 2002. Furthermore, 85 human Campylobacter isolates (62 C. jejuni and 23 C. coli isolates) collected from 2002 to 2004 were included because of presumed reduced susceptibility, based on disk diffusion, against erythromycin and/or ciprofloxacin. Eighty-one of these 85 patients had been abroad; travel history was not known for 3 patients, and 1 patient had not been abroad.The antimicrobial agents evaluated were telithromycin (Aventis Pharma S.A., Antony, France), erythromycin (Sigma, St. Louis, Mo.), doxycycline (Orion, Espoo, Finland), ciprofloxacin (Bayer, Leverkusen, Germany), and moxifloxacin (Bayer). The MICs for the isolates were determined by an agar dilution method according to the recent tentative CLSI (formerly NCCLS) guidelines (10, 12). Mueller-Hinton agar (Oxoid, Basingstoke, United Kingdom) supplemented with 5% defibrinated sheep blood was used. C. jejuni strain ATCC 33560 (12) was included as a control organism. For the quality control of moxifloxacin and telithromycin, Staphylococcus aureus strain ATCC 29213 and Escherichia coli strain ATCC 25922 were included. The plates were incubated in a microaerobic atmosphere at 36°C for 48 h.Susceptibilities to erythromycin and ciprofloxacin were also determined by disk diffusion. Inocula from overnight growth were suspended in sterile saline to match a MacFarland standard of 0.5. Horse blood agar plates were inoculated, and disks (Oxoid) including erythromycin (15 g) and ciprofloxacin (5 g) were added. Plates were incubated as described above.MICs of the tested antimicrobial agents for the domestic strains are shown in Table 1. The majority (70%) of the strains inhibited by erythromycin at 0.5 to 4 g/ml showed MICs of 2 g/ml or less of telithromycin. The growth of one domestic isolate was inhibited by erythromycin at a concentration of 8 g/ml, while 118 isolates (30.0%) had telithromycin MICs of Ͼ2 ...

Antimicrobial Susceptibilities of Multidrug-Resistant Campylobacter jejuni and C. coli Strains: In Vitro Activities of 20 Antimicrobial Agents

“…This finding is consistent with data from previous studies showing that the C. coli strains are macrolide resistant more often than C. jejuni strains (8,23). Because of the increasing trend of resistance among Campylobacter spp., routine susceptibility testing is an important tool to choose an appropriate antimicrobial treatment for the patient.…”

Inaccuracy of the Disk Diffusion Method Compared with the Agar Dilution Method for Susceptibility Testing of Campylobacter spp

“…In some of those studies, the results have been in line, though in some other studies, inconsistencies between the methods have been observed (8,9,15,(17)(18)(19)(20). Nevertheless, the disk diffusion test is currently widely used, since it is easy to perform in clinical microbiology laboratories.…”

“…Several previous papers have focused on the efficacy and accuracy of the disk diffusion method and the Etest method compared to the agar plate dilution or broth microdilution methods, with somewhat contradictory results (8,9,15,17,19,20). In these studies, the disk diffusion tests were performed only once for each strain.…”

Identification of Campylobacter spp. Isolates with Phenotypic Methods and Multiplex Polymerase Chain Reaction and Their Antibiotic Susceptibilities

“…Birçok ülkede yapılan çalışmalarda gastroenterit etiyolojisinde C.jejuni başta olmak üzere kampilobakterlerin en sık rastlanan etken olduğu vurgulanmaktadır 4,[19][20][21][22][23] . Hamidian ve arkadaşlarının 19 İran'da yaptıkları çalışmada, ishalli hastaların %8.7 (49/562)'sinden Campylobacter spp.…”