Susceptibility of clinical isolates of Campylobacter jejuni to sixteen antimicrobial agents

We determined MICs of 20 antimicrobial agents for 50 representative strains of four subgroups of Campylobacter-like organisms (CLOs) by agar dilution. Ampicillin, gentamicin, doxycycline, tetracycline, ceftriaxone, rifampin, spectinomycin, nalidixic acid, and chloramphenicol were active against all strains of CLOs. Most CLO strains (83%) were inhibited by 4 ,ug of sulfamethoxazole per ml and by 8 ,Ig of trimethoprim-sulfamethoxazole per ml. Of type 1 strains, 28% were resistant to 8 ,g of erythromycin per ml. In addition, cross resistance between erythromycin and clindamycin was always present. Type 1 strains exhibited a broad distribution of MICs of metronidazole and streptomycin, whereas all type 2 strains were uniformly susceptible to metronidazole and resistant to streptomycin. Unlike type 1 and 3 strains, type 2 CLOs were susceptible to cephalothin and penicillin G and highly resistant to streptomycin. The type 3 strain was uniquely resistait to cefazolin. The majority of strains were not inhibited by cefoperazone; and all were resistant to trimethoprim. In contrast to Campylobacterjejuni and Campylobacterfetus subsp. fetus, ail CLOs tested were susceptible to 0.5 ,ug of rifampin per ml.Increased awareness of the role of Campylobacter spp. in human disease and the development of improved selective media have resulted in recent isolation of several novel Campylobacter spp. from humans (7,8,10,13,14,(16)(17)(18). Among these, we isolated Campylobacter-like organisms (CLOs) from symptomatic and asymptomatic homosexual nmen being evaluated for enteritis, proctitis, and proctocolitis in a sexually transmitted diseases clinic. These organisms were isolated by using, a selective medium containing vancomycin, polymyxin B, trimethoprim, and amphotericin B supplemented with 10%o sheep blood (2) after incubation at 37°C in a microaerophilic environment. The classification of these CLOs within the genus Campylobacter and their phenotypic characterization into three subgroups were recently described by Fennell et al. (8). Further studies revealed four genetically distinct CLO subgroups (types 1A, 1B, 2, and 3), two of which (types 1A and 1B) were phenotypically identical (21a). The spectrum of diseases associated with CLO infection includes asymptomatic gastrointestinal colonization (17), proctocolitis (17)

Section: Resultsmentioning

confidence: 99%

“…fetus by their susceptibility to <40 p.g of nalidixic acid per ml (12,24,25). CLO type 1 and 2 strains were susceptible to cefazolin but strains of C. jejuni that are susceptible to this antimicrobial agent have not been reported (11,15).…”

Section: Resultsmentioning

confidence: 99%

In vitro susceptibilities of Campylobacter-like organisms to twenty antimicrobial agents

Flores¹,

Fennell²,

Holmes³

et al. 1985

“…C. jejuni and C. coli have rough LPS (28,41) and, according to the models drawn for E. coli and Salmonella typhimurium, should have increased susceptibility to hydrophobic compounds. The literature shows that C. jejuni is more susceptible to doxycycline (mean MIC9Q, 11 ,ug ml-'; 15,17,24,29,55) than to tetracycline (mean MIC90, >24 ,ug ml-,; 5,9,24,26,29,47,53,55,56), which is less hydrophobic (27). C. jejuni is resistant to rifampin (mean MIC90, >87 ,g ml-'; 24, 47) but susceptible to the more hydrophobic derivative ansamycin (mean MIC90, 0.62 ,ug ml-'; 12,52).…”

Section: Resultsmentioning

confidence: 99%

Characterization of the porins of Campylobacter jejuni and Campylobacter coli and implications for antibiotic susceptibility

Page

Huyer

et al. 1989

The major outer membrane protein was extracted from Campylobacter coli by Triton X-100/EDTA fractionation of cell envelopes. This heat-modifiable protein was shown to have pore-forming activity in black lipid bilayers. The C. coli porin formed a relatively small cation-selective pore with a mean single-channel conductance of 0.53 + 0.16 nS in 1.0 M KCI. There was no evidence of oligomer formation, which suggested that each protein monomer formed a pore. Pore-forming activity of the C. coli porin and similarly prepared Campylobacterjejuni porin was also measured in liposome-sweiling assays. These results confirmed the cation selectivity of both pores. The C. coli porin formed a small pore, which hindered the penetration of solutes with a molecular weight of 262, and a larger pore, which hindered the penetration of solutes with a molecular weight of 340, in a protein-concentration-dependent manner. C. jejuni formed one size of pore that was slightly larger than the C. coli pore and just permitted the passage of solutes, with a molecular weight of 340.

“…In Table 2 the comparative numbers of resistant strains for C. jejuni and C. coli in 1978 (n = 78) and 1988 (n = 137) are illustrated. For this comparison the national breakpoints recommended by The frequent use of doxycycline or erythromycin over the past 10 years may have led to an increased number of resistant strains observed in several studies (11,12,20,26). All the strains resistant to doxycycline and 90% of the strains resistant to erythromycin in this study were isolated from patients who were infected abroad.…”

mentioning

confidence: 99%

Antimicrobial susceptibilities of Campylobacter jejuni and Campylobacter coli isolated in Sweden: a 10-year follow-up report

Sjögren

Kaijser

Werner

1992

Resistance to erythromycin and doxycycline and more recently to fluoroquinolones has been reported to occur in Campylobacter spp. both in vitro and in patients treated with these antibiotics. The frequency of resistance to 14 antimicrobial agents in Campylobacter jejuni and Campylobacter coli isolated from patients infected in Sweden or abroad is described. For some agents, a comparison of susceptibility in strains of Campylobacter spp. isolated in 1978 with those isolated in 1988 is made. No general increase in in vitro resistance to antibiotics commonly used for the treatment of human gastroenteritis caused by C. jejuni or C. coli has occurred during the last 10 years in Sweden, which might be a consequence of strict antibiotic control. The numbers of strains from 1988 to 1989 resistant to ciprofloxacin and to norfloxacin included in this study (0.7 and 1.4%, respectively) are still fewer than those that were resistant to erythromycin (7.3%) or doxycycline (12.4%). There is, however, since 1989 to 1990 an indication of increasing resistance to these antibiotics.