Nationwide Survey of Stool Culture Methods for the Diagnosis of Bacterial Gastroenteritis in Korea, 2016

ABSTRACT

BACKGROUND: Stool cultures are essential for diagnosing bacterial gastrointestinal infections. Laboratory procedures and target organisms for stool culture testing can vary by institute. Therefore, a nationwide survey was conducted to determine the stool culture procedures performed in clinical laboratories of Korea. METHODS: Questionnaires were delivered by electronic mail to 98 clinical microbiologists and by Google survey to the 301 institutes participating in the Korean External Quality Control Program of Bacterial Cultures. RESULTS: Of the 68 institutes sent complete responses, Gram staining and wet smears were performed in 73.5% and 64.7%, respectively. A molecular test was conducted in 32.4% of laboratories, and blood agar plates were used in 23.5%. Staphylococcus aureus , Pseudomonas aeruginosa , and Candida species were reported for predominant growth by 17.6%, 8.8%, and 7.4% of the respondents, respectively. Campylobacter culture was available only in 25.0% of laboratories, whereas Clostridium difficile could be cultivated in 38.2%. Susceptibility testing results of Salmonella-Shigella were reported for all tested antibiotics in 22.1% of laboratories, whereas 69.1% reported results for antibiotics specified by the Clinical and Laboratory Standard Institute guidelines. CONCLUSIONS: Methods and results of gram staining, wet smears, use of stool culture media, target microorganisms, and antibiotic susceptibility differed among the institutes. Further discussion is needed to develop a standardized protocol for stool culture to maximize isolation of bacterial pathogens that cause gastroenteritis.