Validation of low-temperature steam with formaldehyde sterilization for endoscopes, using validation device.

BACKGROUND: Validation of sterilization is an important step before clinical use of medical equipment. Adequate validation of sterilization of the endoscope has not been reported. One reason for this is the lack of suitable devices for validation. METHODS: The VDES (validation device for endoscope sterilization; Olympus prototype model, Olympus, Tokyo, Japan) was designed in two types (type A and type B) and resembles gastroscopes and duodenoscopes, respectively. Each type consists of inner and outer tubing and a central capsule containing a biological indicator. The device was designed to examine the effectiveness of low-temperature sterilizers, such as ethylene oxide gas, hydrogen peroxide gas plasma, and low-temperature steam with formaldehyde (LTSF) sterilizer. The aim of this study was to validate the sterilization of GI endoscopes by the LTSF sterilizer. Sterilization was assessed using both types of VDES after a 60-min application of LTSF. RESULTS: Culture of the biological indicator confirmed the complete eradication of the bacteria in a total of 10 experiments with each type of VDES after LTSF sterilization. CONCLUSIONS: Our results confirm that the LTSF sterilizer may sterilize endoscopes currently distributed by Olympus. Commercialization of VDES will make it possible to evaluate the reliability of sterilization when it is set in the sterilization device with endoscopes.