Abstract: 【Abstract】Objective To identify the clinical applicability of a novel tryptone glucose extract agar (TGEA) medium for the detection of bacteria in dialysis water. Methods Water samples were collected from the four hemodialysis centers at the outlet of water treatment system, backwater point of water treatment system, hemodialysis machine (inlet hose connected to the dialysis machine), and diluted dialysate. Samples were cultured with TGEA medium using spreading method (20 ℃, 168 hours) and TGEA membrane filtration method (20 ℃, 168 hours), and with nutrient agar medium (37 ℃, 48 hours) as the control medium. TGEA medium (20 ℃, 168 hours) was used as a validation medium, and bacterial colonies were counted at the end of the culture. Results The value of log10(colony counts) had no significant differences between the TGEA spreading method, the TGEA membrane filtration method, and the validation medium method, but was higher than that of nutrient agar medium method (F=3.346, P=0.025). The detection rate of bacteria was higher from the three TGEA media than from nutrient agar medium, but P value was greater than 0.05 probably due to the limited sample size (χ2=4.267, P=0.234). Bland-Altman analysis showed that the result from validation medium was consistent with the results from TGEA spreading method and TGEA membrane filtration method. The colony number ratios of validation medium/TGEA spreading method and validation medium/ membrane filtration method were all in the range of 0.5～1.5. Conclusion The novel TGEA medium is well applicable for clinical use. The culture process using the novel TGEA medium is easy to operate in a routine environment.

Key words: novel tryptone glucose extract agar medium, clinical applicabilit, , dialysis water, bacterial culture