Surveillance culture of endoscope to monitor the quality of high-level disinfection of gastrointestinal reprocessing.

Background/aims: Inadequate reprocessing of endoscopes or endoscopic accessories may result in iatrogenic infection and present a risk to public health. The aim of this study is to utilize microbiological cultures of endoscopes to assess the adequacy of standard reprocessing procedures.

Methodology: A prospective study to randomly cultures of endoscopes and colonoscopies immediately after the completion of the decontamination cycle monthly. The samples were obtained by flushing 50 ml sterile distilled water to the internal channel and collected into a sterile container. These samples were incubated at 37 degrees C and examined for bacterial growth.

Results: A total of 49 cultures were obtained from June to December in year 2005. Three out of 7 were culture positive in the first month initially, but after prolonged the soaking duration to 25 minutes, the subsequent cultures were reduced to 1 positive sample only. The positive culture rate was 18.4% (9/49), and 44.4% (4/9) in Monoflora culture and 55.6% (5/9) in Multi-flora. Upper endoscopes decontaminated by automated endoscopic washing machine labeled as number 5 was found persistently culture positive with varied organisms despite vigorous manual cleaning and prolonged disinfectant soaking duration. At repair, the relief valve in the automated endoscopes washing machine was damaged and disconnected. After repair, subsequent cultures were negative.

Conclusions: Endoscopy culturing is a useful method to assess the effectiveness of standard reprocessing procedures. Servicing of automated endoscope washer regularly is mandatory to minimize cross infection and quality assurance.