Fluoroquinolone antibiotic users select fluoroquinolone-resistant ESBL-producing Enterobacteriaceae (ESBL-PE) - Data of a prospective traveller study.
BACKGROUND
One third of travellers to the poor regions of the (sub)tropics become colonized by extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE). Co-resistance to non-beta-lactam antibiotics complicates the treatment of potential ESBL-PE infections.


METHODS
We analysed co-resistance to non-beta-lactams among travel-acquired ESBL-PE isolates of 90 visitors to the (sub)tropics with respect to major risk factors of colonization: destination, age, travellers' diarrhoea (TD) and antibiotic (AB) use.


RESULTS
Of the ESBL-PE isolates, 53%, 52%, 73%, and 2% proved co-resistant to ciprofloxacin, tobramycin, co-trimoxazole, and nitrofurantoin, respectively. The rates were similar among those with (TD+) or without (TD-) travellers' diarrhoea. Among fluoroquinolone-users vs. AB non-users, the co-resistance rates for ciprofloxacin were 95% versus 37% (p = 0.001), for tobramycin 85% versus 43% (p = 0.005), co-trimoxazole 85% versus 68% (p = 0.146), and nitrofurantoin 5% versus 2% (p = 0.147). In multivariable analysis co-resistance to ciprofloxacin was associated with increasing age, fluoroquinolone use, and tobramycin resistance.


CONCLUSIONS
While TD predisposes to ESBL-PE non-selectively, antimicrobial use favours strains resistant to drug taken and, simultaneously, any drug with resistance genetically linked to the drug used. Antibiotics taken during travel predispose to ESBL-PE with a high co-resistance rate.
Inflammation Center, Division of Infectious Diseases, University of Helsinki and Helsinki University Hospital, POB 348, FIN-00029 HUS, Helsinki, Finland; Aava Travel Clinic, Medical Centre Aava, Annankatu 32, FIN-00100 Helsinki, Finland; Unit of Infectious Diseases, Karolinska Institutet, Solna, SE-17176 Stockholm, Sweden. Electronic address: anu.kantele@hus.fi.
Anu
A
Kantele
Division of Clinical Microbiology, Helsinki University Hospital, HUSLAB, POB 400, FIN-00029 HUS, Helsinki, Finland. Electronic address: sointu.mero@hus.fi.
Sointu
S
Mero
Division of Clinical Microbiology, Helsinki University Hospital, HUSLAB, POB 400, FIN-00029 HUS, Helsinki, Finland. Electronic address: jussi.kirveskari@luukku.com.
Juha
J
Kirveskari
Inflammation Center, Division of Infectious Diseases, University of Helsinki and Helsinki University Hospital, POB 348, FIN-00029 HUS, Helsinki, Finland. Electronic address: tinja.laaveri@hus.fi.
Tinja
T
Lääveri
D000293:Adolescent; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002353:Carrier State / Q000453:epidemiology / Q000382:microbiology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D024881:Drug Resistance, Bacterial; D004755:Enterobacteriaceae / Q000187:drug effects* / Q000302:isolation & purification; D004756:Enterobacteriaceae Infections / Q000453:epidemiology / Q000382:microbiology; D005243:Feces / Q000382:microbiology; D005260:Female; D024841:Fluoroquinolones / Q000494:pharmacology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D012307:Risk Factors; D014195:Travel / Q000706:statistics & numerical data*; D055815:Young Adult; D001618:beta-Lactamases
D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D001618:beta-Lactamases
Antibiotics; Colonization; ESBL; Extended-spectrum beta-lactamase; Travel