Development and evaluation of a loop-mediated isothermal amplification assay for rapid and simple detection of Campylobacter jejuni and Campylobacter coli

Abstract

We developed a loop-mediated isothermal amplification (LAMP) assay for the rapid and simple detection of Campylobacter jejuni and Campylobacter coli. The assay provides a specific LAMP product for each of these two species. The assay correctly identified 65 C. jejuni and 45 C. coli strains, but not 75 non-C. jejuni/coli strains. The sensitivity of the LAMP assay for C. jejuni and C. coli in spiked human stool specimens was 5.6 x 10(3) c.f.u. g(-1) (1.4 c.f.u. per test tube) and 4.8 x 10(3) c.f.u. g(-1) (1.2 c.f.u. per test tube), respectively. When 90 stool specimens from patients with diarrhoea were tested by LAMP and direct plating, the LAMP results showed 81.3 % sensitivity and 96.6 % specificity compared to isolation of C. jejuni and C. coli by direct plating. Further, the LAMP assay required less than 2 h for detection of C. jejuni and C. coli in stool specimens. This LAMP assay is a rapid and simple tool for the detection of C. jejuni and C. coli and will be useful in facilitating the early diagnosis of food poisoning incidents caused by these organisms.