Evaluation of different culturemedia for detection and quantification of H. pylori in environmental and clinical samples

Abstract

[EN] The objective of the present study was to establish the most suitable culture medium for the isolation ofH. pylorifrom environmental and clinical samples. Ten different culture media were compared and evaluated. Four of them had been previously described and were modified in this study. The rest of the media were designed de novo. Three different matrices, tap water, wastewater, and feces, were inoculated with serial dilutions ofH. pyloriNCTC 11637 strain at a final concentration of 10(4)and 10(3) CFU/ml and the recovery rates were calculated. From inoculated tap water and wastewater samples,H. pyloricolonies were recovered from four out of the analyzed culture media. When fecal samples were analyzed, the isolation of the pathogen under study was only possible from two culture media. Different optimal media were observed for each type of sample, even for wastewater and stool samples. Nevertheless, our results indicated that the combination of Dent Agar with polymyxin B sulfate did not inhibit the growth ofH. pyloriand was highly selective for its recovery, regardless of the sample origin. Thus, we propose the use of this medium as a diagnostic tool for the isolation ofH. pylorifrom environmental and clinical samples, as well as for epidemiological studies.