-Report on Experiments and Clinical Cases-

A Comparative Study of Sterility Levels in Continuous Ambulatory Peritoneal Dialysis System

Sabine Kyoko Saito¹, Tetsuya Kashiwagi¹, Hideyasu Miyahara², Yasuhiko Iino¹ and Yasuo Katayama¹

¹Department of Neurological, Nephrological, and Rheumatological Science, Graduate School of Medicine, Nippon Medical School
²Research and Development, JMS Co., Ltd.

Introduction: Peritonitis remains a serious risk associated with continuous ambulatory peritoneal dialysis (CAPD), although better patient education programs and such technological advances as improved automated connecting devices have greatly decreased its incidence over the past 20 years. The automated devices have a good resistance to contamination, but they rely on an external electrical power source and are not easily portable. There has, therefore, been a need for a highly sterile nonelectric manual connecting device to complement the automated devices already in use. Such a manual device has recently been developed. We compared the level of sterility after touch contamination in this new device with levels in 2 other connecting devices: a conventional device with a manual cap (JMS Co. Ltd., Hiroshima, Japan), and a powered total containment device (JMS Co. Ltd.).
Method: Five bacteria frequently causing CAPD-related peritonitis (Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans) were separately applied to the tip of each connecting device, and peritoneal washing fluid was injected as in a routine exchange. We used a membrane filter method to determine whether the route had been contaminated by the washing fluid.
Results: In the conventional device with a manual cap, 3 to 4 colony-forming units (CFUs) of S. aureus were detected in 2 of 10 drainage samples, 8 CFUs of E. coli in 1 of 10 drainage samples, and 1 CFU of E. coli in the injection fluid. In contrast, no contamination was detected in the automated connecting device or the new manual cap device.
Conclusion: This study confirmed that the new device has a risk of touch contamination lower than that of the conventional manual cap device and equal to that of the automated device. Being easily portable and not reliant on an external power source, the new device should be useful in various situations.

J Nippon Med Sch 2010; 77: 306-311

Keywords
peritonitis, continuous ambulatory peritoneal dialysis, connecting device, touch contamination

Correspondence to
Sabine Kyoko Saito, Division of Neurology, Nephrology, and Rheumatology, Department of Internal Medicine, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603, Japan
s2037@nms.ac.jp

Received, April 12, 2010
Accepted, July 6, 2010