engleski

Combined ciprofloxacine and tetracycline resistance among C. jejuni human faecal isolates in the largest Croatian county: a cross-sectional study

Objectives: C. jejuni is the leading bacterial foodborne pathogen worldwide and antimicrobial susceptibility testing is essential to provide guidance on appropriate treatment. Resistance rates differ between countries which affects control measures. No surveillance data on Campylobacter resistance have been reported for Croatia. The goal of our study was to estimate antimicrobial resistance rates of C. jejuni human fecal isolates to erythromicine, ciprofloxacine, gentamycine and tetracycline in the largest Croatian county and to compare resistance rates of hospitalized and outpatients isolates. Methods: The study is part of laboratory-based Campylobacter surveillance study performed in Split-Dalmatia County. 153 human fecal C. jejuni isolates were collected consecutively between May 2012. and April 2013.: 76 isolates from hospitalized and 77 from outpatients samples. All patients were symptomatic ; with hospitalized having more severe clinical course. Isolation was done by primary plating on selective media and incubation at 42°C in a microaerobic atmosphere. Campylobacter isolates were identified to species level using standard biochemical and ApiCampy tests (Biomerieux). E- tests (©AB BIODISK, Biomerieux) were used to determine the MIC for tested antibiotics. MIC?s were interpreted according to CLSI guidelines. Results: None of the stool samples were resistant to gentamycine and only one (1%) was resistant to erythromicine. The strain, isolated from an outpatient, was also the only one exhibiting muliple resistance: to erythromicine, ciprofloxacine, and tetracycline. Estimated resistance rate of C.jejuni to ciprofloxacine was high: 60%, with 83 (54%) isolates classified as resistant, and 9 (6%) as intermediate susceptible . Similarly, tetracycline resistance rate was estimated to 24%, with 29 (19%) resistant and 7 (5%) intermediate susceptible isolates. Significant association between ciprofloxacine and tetracycline resistance was observed in the overall sample (Fisher exact, P=3.2*10-5) as well as in stratified analysis by the patient status (P<0.015). Post hoc analysis revealed the association was due to significant increase in the frequency of isolates resistant to both antibiotics (32 or 21%), and decrease of isolates with ciprofloxacine susceptibility and tetracycline resistance (4 or 3%). No difference in resistance rates, combined resistance to ciprofloxacine and tetracycline or sex distribution was found between hospitalized and outpatients groups. In both groups a characteristic bimodal age distribution was observed, with hospitalized patients having more pronounced peak around 60- 65 years. Conclusions: A high resistance to ciprofloxacine and tetracycline is concern for public health and warrant urgent change in antimicrobial use policy. Strong association of resistance to both antibiotics needs to be elucidated. Evidence from hospitalized and outpatients suggest no association between antimicrobial resistance and C.jejuni virulence. Study results suggest macrolides or gentamycine for empirical treatment of C.jejuni infections when antimicrobial therapy is warranted. Resistance emergence could affect health globally through international travel and trade and it?s especially important in our county that is popular touristic destination.

Campylobacter jejuni; ciprofloxacine; tetracycline; resistance; human; Croatia

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