Evaluation of BacT/Alert FAN Plus Bottles for the Culture of Peritoneal Dialysate

민승 박1   인영 유1   오균 강1   정은 이2   대중 김2   희재 허*1   남영 이*1   

1 Department of Laboratory Medicine and Genetics,
2 Division of Nephrology, Department of Medicine,Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul

Abstract

Background: A major complication of peritoneal dialysis (PD) is peritonitis, and bacterial culture of PD effluent in a blood culture bottle is the preferred technique for diagnosis of peritonitis. In this study, we compared dialysate inoculation and culture using the BacT/AlerTⓇ Fastidious Antimicrobial Neutralization Plus blood culture bottles (FAN Plus; bioMérieux, France) to the conventional centrifugation culture method.

Methods: A total of 170 PD effluents were simultaneously processed by the conventional centrifugation culture method and by culture using FAN Plus media with two different inoculation procedures: inoculation after centrifugation and direct bedside inoculation.

Results: Of the 52 cultures that were positive on at least one of the culture methods, 27 samples were positive on conventional centrifugation. However, 46 samples showed growth following inoculation into the FAN Plus media after centrifugation, and 47 samples were positive on the direct FAN Plus inoculation method. Using the case definition for PD peritonitis to classify samples, sensitivity of the conventional method was 50.0% (95% CI, 33.7-66.3%), whereas the sensitivity of the FAN Plus media was 78.9% (95% CI, 62.2-89.9%) by inoculation after centrifugation and 86.8% (95% CI, 71.1-95.1%) by direct inoculation. Use of both inoculation methods with FAN Plus media resulted in 92.1% sensitivity (95% CI, 89.2-99.9%).

Conclusion: Culture using FAN Plus media demonstrated a superior bacterial recovery rate to the conventional centrifugation culture method. A combination of the two inoculation methods with FAN Plus media is recommended for the best diagnostic yield, while direct inoculation alone can be useful due to its simplicity and cost-effectiveness. (Ann Clin Microbiol 2019;22:90-95)

Keywords

BacT/AlerT 3D system   Centrifugation   Culture media   FAN Plus blood culture bottle   Peritoneal dialysis   Peritonitis   


Acknowledgements

We are grateful to the advanced practice nurse of peritoneal dialysis, Jaesun Moon.

Figures & Tables

Table 1. The recovery of microorganisms following culture methods in FAN Plus media compared the conventional centrifugation culture method

MethodResultConventional centrifugation culture (no. of specimens)P value
PositiveNegativeTotal
FAN Plus inoculation after centrifugationPositive271946<0.001
Negative0124124
Total27143170
Direct FAN Plus inoculationPositive26 47<0.001
Negative1122123
Total27143170
Combination of two methods using FAN Plus mediaPositive272552<0.001
Negative0118118
Total27143170