Chu N S, McAlister D, Antonoplos P A
Advanced Sterilization Products, Irvine, California 92618-9824, USA.
Gastrointest Endosc. 1998 Aug;48(2):137-42. doi: 10.1016/s0016-5107(98)70154-3.
Colonoscopes present a special bacterial decontamination challenge because the colon has a large and diverse microbial population.
Bioburden of colonoscope insertion tube surfaces and suction channels were determined after use and after manual cleaning.
After use bioburden in suction channels averaged 7.0 x 10(9) colony-forming units (cfu). Cleaning reduced this level to 1.3 x 10(5). Cleaning of tube surfaces reduced the after-use bioburden from a level of 5.1 x 10(5) to 2.2 x 10(4) cfu. Gram-negative rods accounted for approximately 99% of the bioburden within the suction channel after use and after cleaning. After use flora were predominantly Escherichia coli and Bacteroides. The flora shifted to waterborne Pseudomonas organisms, and other members of the family Enterobacteriaceae after cleaning. Gram-positive bacteria were the primary isolates from the device surfaces both after use (56%) and after cleaning (47%). Because gram-positive cocci and diphtheroids are a part of the normal microbiota of the skin, these bacteria may have been introduced by the hospital environment or by handling.
After the cleaning of in-use colonoscopes, fewer than 10(6) vegetative bacteria could be recovered. This value is several logs lower than some previous estimates. This finding may be useful in the formulation of sterilization and disinfection cycles. Microflora from the colonoscopes indicated that the cleaning process introduced waterborne and enteric microorganisms, which highlights the importance of sanitation in the device reprocessing area.
由于结肠拥有大量且多样的微生物群落，结肠镜的细菌去污面临特殊挑战。
在使用后及人工清洗后，测定结肠镜插入管表面和吸引通道的生物负荷。
使用后，吸引通道中的生物负荷平均为7.0×10⁹菌落形成单位（cfu）。清洗后该水平降至1.3×10⁵。管表面的清洗使使用后的生物负荷从5.1×10⁵cfu降至2.2×10⁴cfu。使用后及清洗后，革兰氏阴性杆菌约占吸引通道内生物负荷的99%。使用后菌群主要为大肠杆菌和拟杆菌。清洗后，菌群转变为水生假单胞菌属生物以及肠杆菌科的其他成员。革兰氏阳性菌是使用后（56%）和清洗后（47%）器械表面的主要分离菌。由于革兰氏阳性球菌和类白喉杆菌是皮肤正常微生物群的一部分，这些细菌可能是由医院环境或操作引入的。
使用后的结肠镜清洗后，回收的活菌数少于10⁶。该数值比之前的一些估计低几个对数级。这一发现可能有助于制定灭菌和消毒周期。结肠镜的微生物群落表明，清洗过程引入了水生和肠道微生物，这凸显了器械再处理区域卫生的重要性。
