1Department of Clinical Microbiology, Athens Medical School, Aeginition Hospital, Vass. Sophias av. 7274, 115 28 Athens; 2Department of Microbiology, Penteli Childrens Hospital, Athens; 3Department of Microbiology, Athens Medical School, Athens, Greece
Received 27 March 2001; returned 6 December 2001; revised 15 January 2002; accepted 23 January 2002.
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Abstract |
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Introduction |
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Because of the low mortality and the self-limiting nature of C. jejuni infection, treatment is not justified unless the patient is immunocompromised.4 When indicated, erythromycin is the antimicrobial of choice. Ampicillin, co-amoxiclav and fluoroquinolones are recommended as alternative therapies. However, in the last 5 years there have been several reports of increasing resistance of C. jejuni to quinolones.5,6 In Greece the first reported ciprofloxacin-resistant C. jejuni strains were isolated from infected children in 1993.7
The aim of the present study was to determine and compare the in vitro antimicrobial susceptibility patterns to five antimicrobials of C. jejuni isolated from hospitalized children with gastroenteritis, and collected during two time periods: 19871988 (group A) and 19982000 (group B).
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Patients and methods |
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All patients were children up to 14 years with gastroenteritis, presenting in the out-patient department of the Childrens Hospital of Penteli in Athens. Stool specimens were collected and sent for bacteriological examination on the day of hospitalization. None of the patients had received any kind of antibiotic treatment before bacteriological examination. A total of 129 C. jejuni strains were collected during two periods: 31 during 19871988 (group A) and 98 during 19982000 (group B). All strains were kept frozen in liquid nitrogen until the day of examination. MIC determination was performed simultaneously in both groups.
Stool culture for Campylobacter
For the isolation of Campylobacter, stools were plated on Skirrows selective medium and incubated for 48 h at 42°C in a microaerophilic atmosphere (Genbox-microaer; bio-Mérieux, Marcy lÉtoile, France). C. jejuni was identified by typical growth, microscopic examination, hippurate hydrolysis, and positive catalase and oxidase reactions. Strains were suspended in stock culture medium containing trypticase soy broth with 20% glycerol and stored at 80°C.
MIC determination
Determination of MICs of erythromycin, nalidixic acid, ciprofloxacin, ampicillin and co-amoxiclav was performed by the standard agar dilution method.8 Antimicrobials were obtained as pure powders (Sigma Diagnostics, St Louis, MO, USA). Serial dilutions of antimicrobial stock solutions were prepared and incorporated in MuellerHinton agar containing 5% lysed horse blood. Bacterial suspensions in MuellerHinton broth were inoculated using a multipoint inoculator (MAST Laboratories, Bootle, UK) at a density of 105 cfu/mL and a volume of 10 µL per spot. Plates were incubated for 24 h at 42°C in a microaerophilic atmosphere. The MIC was defined as the lowest concentration of the antimicrobial that completely prevented visible growth. Results were interpreted according to the criteria of the NCCLS for Enterobacteriaceae (breakpoints are given in Table 1).
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Results |
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Determination of MIC50s and MIC90s are shown in Table 2. Particularly noteworthy is the net shift of MIC90 to the side of resistance from group A to group B for nalidixic acid and ciprofloxacin, and the reverse shift (to the side of susceptibility) for erythromycin (Table 2). The MIC90s of ampicillin and co-amoxiclav remained unchanged from one time period to the other, although there was a significant decrease in MIC50s of these antimicrobials in group B compared with those of group A (Table 2)
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Discussion |
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The antimicrobial treatment for Campylobacter is often initiated before the results of antimicrobial susceptibility testing are available; therefore, a general knowledge of the expected susceptibility of Campylobacter is a prerequisite to start treatment with an appropriate antimicrobial agent. The establishment of a simple surveillance system for recording and reporting data would be of great assistance and would improve the implementation of correct treatment.
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Acknowledgements |
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Footnotes |
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References |
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2 . Cover, T. L. & Blaser, M. J. (1989). The pathobiology of Campylo-bacter infections in humans. Annual Review of Medicine 40, 26985.[ISI][Medline]
3 . Speed, B., Kaldor, J. & Cavanogh, P. (1984). GuillainBarré syndrome associated with Campylobacter jejuni enteritis. Journal of Infection 8, 856.[ISI][Medline]
4 . Mishu, B. & Blaser, M. J. (1975). Campylobacter jejuni and the expanding spectrum of related infections. Clinical Infectious Diseases 20, 10918.
5 . Reina, J., Ros, M. J. & Serra, A. (1994). Susceptibilities to 10 antimicrobial agents of 1220 Campylobacter strains isolated from 1987 to 1993 from feces of pediatric patients. Antimicrobial Agents and Chemotherapy 38, 291720.[Abstract]
6 . Sanchez, R., Fernandez-Baca, V., Diaz, M. D., Miñoz, P., Rodriguez, M. & Bouza, E. (1994). Evolution of susceptibility of Campylobacter species to quinolones and macrolides. Antimicrobial Agents and Chemotherapy 38, 187982.[Abstract]
7 . Chatzipanagiotou, S., Papavassiliou, E. & Malamou-Lada, E. (1993). Isolation of Campylobacter jejuni strains resistant to nalidixic acid and fluoroquinolones from children with diarrhea in Athens, Greece. European Journal of Clinical Microbiology and Infectious Diseases 12, 5668.[ISI][Medline]
8 . National Committee for Clinical Laboratory Standards. (1997). Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria that Grow Aerobically: Approved Standard M7-A4. NCCLS, Wayne, PA, USA.
9 . Gaunt, P. N. & Piddock, L. J. V. (1996). Ciprofloxacin resistant Campylobacter spp. in humans: an epidemiological and laboratory study. Journal of Antimicrobial Chemotherapy 37, 74757.[Abstract]
10 . Husmann, M., Feddersen, A., Steitz, A., Freytag, C. & Bhakdi, S. (1997). Simultaneous identification of campylobacters and prediction of quinolone resistance by comparative sequence analysis. Journal of Clinical Microbiology 35, 2398400.[Abstract]
11 . Ruiz, J., Goni, P., Marco, F., Gallardo, F., Mirelis, B., Jimenez De Anta, T. & Vila, J. (1998). Increased resistance to quinolones in Campylobacter jejuni: a genetic analysis of gyrA gene mutations in quinolone-resistant clinical isolates. Microbiology and Immunology 42, 2236.[ISI][Medline]
12 . Hooper, D. C. & Wolfson, J. S. (1991). Fluoroquinolone antimicrobial agents. New England Journal of Medicine 324, 38494.[ISI][Medline]