Isolation of Campylobacter from human stool samples.

Context: Campylobacter is an undetected cause of diarrhoea especially under 5 years of age in most of the countries. Isolation of this organism is diffi cult, expensive and cumbersome. Aims: Our objective of this study was to isolate this pathogen from the stool specimens on routinely available blood containing laboratory media using the candle jar for creating the microaerophilic atmosphere in our setup. Settings and Designs: A descriptive study. Materials and Methods: A total of 50 stool samples were inoculated onto selective and non-selective media with and without fi ltration using a 0.45 μm membrane. The inoculated media were simultaneously incubated in microaerophilic conditions using the Anoxomat as well as in candle jars at temperatures 37°C and 42°C. The culture isolates were confi rmed by standard phenotypic tests. A simplex polymerase chain reaction (PCR) targeting the 16S ribosomal deoxyribonucleic acid of Campylobacter was performed on the deoxyribonucleic acid (DNA) of the culture isolates as well as on the DNA extracted from the stool fi ltrates. Statistical Analysis: Data was expressed as a proportion. Results: Campylobacter could be isolated in 5 out of 50 stool samples using both the Anoxomat as well as the candle jar. Furthermore, we did not fi nd any difference between the isolation using the selective and blood containing media as well as the different incubation temperatures. All the fi ve were confi rmed phenotypically and genotypically to be Campylobacter jejuni. The PCR results corroborated with that of the culture. Conclusions: Isolation by culture was as sensitive as that of the PCR.

Anaerobic culture on growth efficient bi-layered culture plate in a modified candle jar using a rapid and slow combustion system.

Success for maximum isolation of anaerobes depends on maintaining critically low oxygen levels throughout and growth in a reduced medium with exclusion of inhibitory substances. Hence a dual system was used equipped with candle combustion for instant exhaustion of major part of oxygen from a sealed jar, along with acidified steel wool for residual oxygen purging. For inhibitory substances removal, test anaerobes were grown on anaerobic medium layered on buffer charcoal agar bed. After 48 hours incubation average colony sizes were compared with that of growths in conventional Gas-Pak system. Better growths were noted in the innovative system.