Background: The rapid and accurate detection of diarrheal pathogens is essential to prevent the spread of diarrheal diseases. Recently, a multiplex PCR assay was developed to simultaneously detect various bacterial and viral diarrheal pathogens. In this study, we investigated the frequency of detection of various potential pathogens causing diarrhea by using multiplex PCR and compared the results to the results of stool culture tests for bacteria and enzyme immunoassays (EIAs) for rotaviruses and Clostridium difficile toxin B (CDTB).
Methods: We retrospectively analysed the results for multiplex PCR, culture tests, and EIA obtained from stool specimens submitted to the laboratory from May 2013 to September 2014. Multiplex PCR was performed using the Seeplex diarrhea ACE detection kit (Seegene, Korea), which detects five viruses and eight bacteria.
Results: Among 890 stool specimens, 408 (45.8%) were found to be positive by PCR. The PCR positivity rate for bacteria and viruses was 31.1% (277/890) and 18.9% (161/890), respectively. The relative frequencies of microorganisms or toxins detected by PCR were, in decreasing order, CDTB 24.0%, Clostridium perfringens 20.6%, norovirus-GII 15.8%, rotavirus 11.3%, Campylobacter spp. 7.5%, enteric adenovirus 5.7%, and Salmonella spp. 5.1%. The concordance rate of the results obtained using the PCR and culture tests was 99.2% for Salmonella spp., 95.7% for Campylobacter spp., and. 79.8% for C. difficile . The concordance rates for rotaviruses and CDTB were 99.7% and 83.6%, respectively.
Conclusions: The multiplex PCR method showed a high detection rate and is useful for the simultaneous detection of various diarrheal pathogens.
(J Lab Med Qual Assur 2015;37:141-147)

Keywords: Diarrhea, Multiplex polymerase chain reaction, Culture, Immunoenzyme techniques

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