Laboratory analysis on one food poisoning event caused by Clostridium perfringens

ObjectiveTo identify the pathogen of one food poisoning event using by three detection methods.

MethodReal-time PCR, digital PCR and plate count culture were applied in the detection of suspected contaminated food samples (salt water pig liver); Pulsed-field gel electrophoresis was performed for the typing of the isolates. Biochemical bacteria identification and real-time PCR were performed for the Clostridium perfringens isolates from the suspected contaminated food samples; digital PCR was performed for the absolute quantification of virulence genes.

Results Plate count culture value of C. perfringens was 4 400 000 CFU/g for the suspected contaminated food samples, and 22 C. perfringens isolates were obtained, which were positive for both plc gene and cpe gene of C. perfringens indicated by real-time PCR; and 3 isolates were plc+/cpe+, 19 isolates were plc+/cpe–. Absolute quantification value of plc gene was 1064 Copies/μl. Twenty two C. perfringens isolates had 2 different PFGE patterns.

ConclusionLaboratory analysis through three detection methods indicated that this food poisoning might be caused by C. perfringens.