Multiplex polymerase chain reaction (PCR) for the detection of diarrheagenic Escherichia coli and Shigella directly from stool

摘要

Shigella?and diarrheagenic?Escherichia coli?(DEC) are the most common causes of diarrheal diseases in developing countries. A multiplex polymerase chain reaction (mPCR) was developed for identification of DEC infections caused by shiga toxin producing?E. coli?(STEC), enteropathogenic?E. coli?(EPEC), enterotoxigenic?E. coli(ETEC), enteroinvasive?E. coli?(EIEC) and?Shigella?in feacal samples by simultaneous and specific detection of seven virulence genes (eaeA,?stx1,?stx2,?bfpA,?LT,?ST?and?ipaH). The detection limit of the method was 101?to 103?cfu/PCR assay?from pure cultures. When the multiplex PCR was tested with DNA purified from artificially spiked stool samples directly from stool or after overnight pre-enrichment in buffered peptone water, the detection limit was106?cfu?and?101?- 105?cfu/gm?stool, respectively. The developed mPCR is specific, sensitive, easy, rapid and of low cost method for detecting DEC in stool.