Epidemiologic Study of Diarrhea Pathogens Detected by Multiplex Real-Time PCR: a Single Center Study During 1 Year.

Background: Acute gastroenteritis is one of the major causes of morbidity and mortality worldwide, especially in children and the elderly. The identification of various diarrhea-causing bacteria using multiplex polymerase chain reaction (PCR) and rapid antigen testing has enabled a more detailed analysis of diarrhea-causing pathogens. Pre-vious reports have a limitation in that they do not include data on multiple infections in which two or more infectious agents are simultaneously detected, and there are no data on clinical information. We investigated various diarrhea-causing bacteria and viruses detected by multiplex real-time PCR for one year at a single institution.

Methods: This study included 766 subjects who underwent multiplex real-time PCR testing of direct stool specimens for the purpose of diagnosis from April 2019 to February 2020. The multiplex PCR test used in our study can simultaneously detect 16 types of bacteria and five types of viruses. When two or more pathogens were detected by multiplex real-time PCR, they were confirmed using single conventional PCR or real-time PCR. Demographic, clinical, and laboratory data were collected from electronic medical records (EMR). The detected bacteria and viruses were analyzed according to age and season.

Results: Out of a total of 352 stool samples with pathogen detection, 265 (75.3%) were detected as single and 87 (24.7%) showed co-detection. The highest rates of single and co-detection were for Clostridium perfringens, and the highest combination of co-infections was for C. perfringens and Staphylococcus aureus.

Conclusions: We demonstrated that different age groups showed varying pathogen distributions. While no special seasonality was found in the monthly distribution, it should be noted that the total number of cases peaked in September. The data presented in our study serves as epidemiologically important basic data.