Antibiotic Resistance Pattern and Detection of Enterotoxigenic and Enteroaggregative Strain of Escherichia coli among Foreign Tourist with Traveler Diarrhea in Bali using Uniplex Polymerase Chain Reaction

Abstract

BACKGROUND: As one of the major tourist destinations in Southeast Asia, Bali received millions of foreign tourists each year. Diarrhea consistently placed as the most often experienced health problem among travelers. Traveler diarrhea has various etiologies. The most common was Escherichia coli. The existence of several types of E. coli that are resistant to several antibiotics causes the selection of antibiotics is crucial.
 AIM: This preliminary study aims to understand the pattern of antibiotics sensitivity and to detect the presence of enterotoxigenic and enteroaggregative strains of E. coli from fecal samples of foreign tourists with traveler’s diarrhea in Denpasar, Bali.
 METHODS: A culture examination was carried out to obtain E. coli bacterial colonies. Disk diffusion Kirby–Bauer was carried out for antibiotic sensitivity testing. The confirmed colonies were tested against several common antibiotics, including the recommended first line (ciprofloxacin and azithromycin). Uniplex polymerase chain reaction (PCR) using specific primers conducted to detect the enterotoxigenic E. coli (ETEC) (elt and estA2-4) and enteroaggregative E. coli (EAEC) (CVD432) strains.
 RESULTS: Among 48 stool culture, 14 (29.2%) were identified as E. coli colonies. All samples were still sensitive to the antibiotics meropenem, ceftazidime, and cefixime. Despite majority of the samples (78.6%) still sensitive to ciprofloxacin, large proportion of the samples have developed resistance against the other commonly used antibiotics, doxycycline (70.4%) and azithromycin (57.1%). PCR showed that 3 (21.4%) samples shown positive for CVD432 gene, 2 (14.3%) samples positive for the elt gene, and all negative for the estA2-4 gene.
 CONCLUSION: An only small proportion of E. coli was EAEC or ETEC strain. Although most E. coli still sensitive to beta-lactam antibiotics, a significant proportion had shown resistance against the commonly recommended first-line antibiotics.