endoscopy is used worldwide for the screening , diagnosis , and treatment of gastrointestinal ( gi ) diseases and enables early detection and treatment of malignant gi diseases . despite its efficacy , there are several reports that raise concerns about infections that are transmitted via endoscopy.123 consequently , several countries have revised evidence - based guidelines on endoscope reprocessing in order to reduce the number of infections and improve safety . in march 2015 ,
herein , we discuss reprocessing protocols for gi endoscopes including recently revised guidelines from medical associations around the world including the multisociety guidelines , european society of gastrointestinal endoscopy ( esge ) guidelines , european society of gastroenterology and endoscopy nurses and associates ( esgena ) guidelines , british society of gastroenterology ( bsg ) guidelines , and world gastroenterology organization ( wgo ) guidelines .
there are seven steps involved in the reprocessing of gi endoscopes : precleaning , cleaning , rinsing , disinfection , rinsing , drying , and storage .
these steps are similar across various guidelines.45678 ( 1 ) precleaning is the first step of reprocessing , and should be conducted at the bedside immediately after completing the endoscopic procedure .
precleaning involves the removal of visible debris by wiping the exterior of the endoscope with an appropriate detergent solution .
after precleaning , endoscopes need to be transported to another room for the disinfection process .
if the room is not adjacent , the container for the endoscopes should be closed .
( 2 ) cleaning is the next step . before cleaning the endoscopes , a leak test should be performed , and all detachable parts should be separated .
clean the external surface of the endoscope with detergent using soft cloths , sponges , or brushes .
hard - to - clean areas or accessories should be cleaned with an ultrasonic cleaner .
( 3 ) rinsing includes flushing the endoscope , channels , and all accessories with sterile water .
( 4 ) high - level disinfection is recommended after the cleaning and rinsing processes .
the endoscope and its components should be completely immersed in a high - level disinfectant solution , ensuring that all channels are well perfused .
selection of high - level disinfectants should be based on us food and drug administration ( fda ) , conformit europene , or korean food and drug administration approval .
the appropriate exposure time and temperature for high - level disinfection are specific to each disinfectant and its concentration .
( 5 ) after disinfection , the endoscope , channels , and all accessories receive a final rinse with sterile water . ( 6 ) the endoscopic channels are dried by flushing with forced air and ethyl or isopropyl alcohol ( 70% to 90% ) .
( 7 ) storage requires keeping the endoscopes in a safe and sterile environment , usually hanging the endoscopes in a vertical position without touching the floor .
in 1995 , the korean society of gastrointestinal endoscopy established the first endoscope reprocessing guideline .
since then , the guidelines have been revised in august 2009 , august 2012 , and march 2015 .
the most recent 3rd revision included the criteria to assess reprocessing for not only the certification of individual medical facilities but also the quality assessment of national cancer endoscopic screening .
the main change in the recently updated guidelines addressed the issue of reprocessing endoscopic accessories .
it is no longer acceptable to reuse single - use ( disposable ) forceps or needles after sterilization .
however , thus far , the korean national health insurance service has not provided appropriate reimbursement for single usage of forceps .
therefore , owing to practical limitations , many clinicians have needed to use single - use forceps .
as stated above , the korean society of gastrointestinal endoscopy updated and clarified the recommendation regarding endoscopic accessories in their third revision .
thanks to their efforts , the reasonable cost of the biopsy forceps can be recovered .
for example , unlike the bsg and esge - esgena guidelines , there is no recommendation for microbiological surveillance .
also , the water bottle and connectors should undergo high - level disinfection every day and the water should be sterilized .
in 2003 , the american society for gastrointestinal endoscopy and the society for healthcare epidemiology of america developed an initial set of guidelines for reprocessing gi endoscopes . updated guidelines
were published in 2011 along with additional discussions on evolving issues and the latest literature citations .
these guidelines use the centers for disease control and prevention system to categorize recommendations , from " category ia " to " no recommendation."7 for instance , " category ia " recommendations regarding high - level disinfectants include the following : fda - approved , high - level disinfectants should be selected .
there are six approved disinfectants : glutaraldehyde , orthophthalaldehyde , peracetic acid , hydrogen peroxide , electrolyzed acid water , and a peracetic acid / hydrogen peroxide blend .
the guideline mentions that when glutaraldehyde is used , it should be at a 2% concentration level at 25 for 20 to 90 minutes .
also , the minimum effective density of the active ingredient should be present in high - level disinfectants and the solution must be checked every day before use .
the solution should be discarded when the concentration of the solution is less than the minimal effective density.791011 unlike other guidelines , these guidelines include recommendations that emphasize protection from exposure to hazards and chemicals for those who participate in reprocessing .
all participants should wear personal protective equipment and work in a safe environment ( category ib and ic ) .
also , they should be educated properly about hazards ( category ic).791012 in addition , these guidelines use the spaulding classification of medical devices , which is used by the fda , the centers for disease control and prevention , epidemiologists , and many other international organizations to determine the effectiveness of disinfection or sterilization . since endoscopes are classified as " semi - critical " devices
high - level disinfection is the destruction of mycobacteria , microorganisms , viruses , fungal spores , and some , but not all , bacterial spores .
biopsy forceps , needles , and cutting instruments such as sphincterotomes , which penetrate the sterile tissue of the vascular structure , are classified as " critical " and should be sterilized.1314 two more recommendations were updated in the 2011 guidelines : ( 1 ) before high - level disinfection , complete cleaning of endoscopes should be more thorough .
( 2 ) hand hygiene , reprocessing tubing with one - way valves , and endoscopic channels are considered potential sources of infection .
in addition , the following four unresolved issues are discussed : ( 1 ) how long can endoscopes be stored between use ?
the association of perioperative registered nurses recommends 5 days , while the association for professionals in infection control and epidemiology recommends 7 days before reprocessing .
( 2 ) how long can water bottles , tubing for air insufflation , lens wash water , waste vacuum canisters , and suction tubing be used before being replaced ?
( 3 ) how long can endoscopes be used before replacement ? determining the durability and longevity of endoscopes requires additional research .
( 4 ) is microbiological surveillance testing required after reprocessing , during storage , or before use of endoscopes ?
the gastroenterological society of australia and the guidelines of the combined esge and the esgena committee recommend this measure .
the necessity of environmental microbiological testing of endoscopes for quality assurance has not been established but warrants further study .
in 1994 , the esge - esgena guideline committee of the esge and the esgena established guidelines for infection control of gi endoscopes . in 2008 , esge - esgena updated the guidelines for cleaning and disinfection of gi endoscopes.4 apart from the seven steps of endoscope reprocessing similar to other guidelines , they provided detailed information for three different available reprocessing methods : automated washer - disinfectors , automated disinfection devices , and manual reprocessing followed by precleaning and manual cleaning . using
the automated washer disinfector includes all the processing steps from the leakage test to drying .
using the automated disinfection device includes rinsing and disinfection , along with final rinsing and drying .
the esge and esgena strongly recommend the use of washer - disinfectors including cleaning and disinfection .
in addition , it ensures highly reliable reprocessing and minimal staff hazard and lowers the risk of scope damage . according to european standard en 14885
, disinfectants are effective at room temperature when they are used manually or in automated disinfection devices.15 they rely on an aldehyde group ( glutaraldehyde , formaldehyde , and orthophthalaldehyde ) or an oxidizing substance ( chlorine dioxide , hypochlorous acid , and peracetic acid and its salts ) .
, balloons can not be autoclaved and the use of reprocessed balloons increases the risk of biliopancreatic duct infection .
likewise , injection needles should be used only once , and in no circumstance should be reprocessed , because dismantling of needles is dangerous and the lumen of the needle is inaccessible for cleaning . they also recommend process validation and microbiological surveillance .
regular microbiological surveillance testing , at intervals less than 3 months , is recommended.16 washer disinfector , endoscopes , and the water used in endoscopy should be tested at the same time . moreover
the 2008 guidelines were updated in 2014 . the process of reprocessing is described in two parts .
the second is automated disinfection by using endoscope washer disinfectors ( ewds ) , followed by drying and storage .
the use of enzymatic detergents to digest mucus and other biological material from endoscopic channels is no longer recommended , because of reports of occupational asthma and skin reactions.1819 these guidelines do not recommend any manual disinfection method .
glutaraldehyde - based disinfectants , widely used disinfectants , are no longer used in the united kingdom owing to two reasons : occupational safety concerns , an example of which is asthma , and the potential risk of residual cross - linked protein or prion material .
there are four other disinfectants that can be used for reprocessing of endoscopes : orthophthalaldehyde ( 0.55% ) , peracetic acid ( 0.2% to 0.35% ) , chlorine dioxide , and electrolytically generated hypochlorous acid.20 accessories that pass through the working channel of endoscopes should be used only once , such as cytology brushes , polypectomy snares , injection needles , biopsy forceps , and most endoscopic retrograde cholangiopancreatography accessories.2122 currently , most biopsy forceps are reused but the discovery of variant creutzfeldt - jakob disease has caused a shift towards single use .
accessories that are not passed through the working channel can be reused when sterilized , such as bottles and bougies . also , heater probes can be reused and should be sterilized.21 bsg guidelines also recommend a microbiological surveillance test for assurance .
the final rinse water should be sampled from the ewd and tested weekly for its microbiological quality in accordance with the current relevant european standard , health technical memorandum , or choice framework for local policies and procedures.23242526
the committee of the wgo is composed of representatives from europe , america , and japan . in 2011
wgo guidelines introduced the standard procedures with alternatives options that could be used when there are certain external limitations .
for example , the cleaning process should be performed with an enzymatic detergent , but it can be performed with a non - enzymatic detergent in case of external limitations . also , if personnel can not rinse the endoscopes and valves with filtered water , they can rinse them under running tap water of drinking - water quality .
endoscopic accessories that penetrate the mucosal barrier should be used only once or sterilized between each use . however , single - use is preferred .
if disposable accessories are to be reused despite external limitations , they should be perfectly sterilized.9102728293031 microbiological surveillance testing is recommended .
samples of the final rinse water from the automatic reprocessor should be subjected to microbiological testing at least weekly.1623242526
different organizational guidelines for reprocessing gi endoscopes are similar , but they include subtle differences ( table 1 ) .
reprocessing of gi endoscopes should be carried out according to recommendations for each step of the process , whether using manual or automated methods .
many associations are trying to develop evidence - based guidelines for the reprocessing of gi endoscopes .
the evolution of disinfectants and automated machines for reprocessing are required to ensure endoscopic safety .
 gastrointestinal endoscopy is effective and safe for the screening , diagnosis , and treatment of gastrointestinal disease . 
 however , issues regarding endoscope - transmitted infections are emerging . 
 many countries have established and continuously revise guidelines for endoscope reprocessing in order to prevent infections . 
 while there are common processes used in endoscope reprocessing , differences exist among these guidelines . 
 it is important that the reprocessing of gastrointestinal endoscopes be carried out in accordance with the recommendations for each step of the process . 
INTRODUCTION
COMMON REPROCESSING PROTOCOL FOR GI ENDOSCOPES
KOREAN GUIDELINES FOR ENDOSCOPE REPROCESSING
MULTISOCIETY GUIDELINES
ESGE-ESGENA GUIDELINES
BSG GUIDELINES
WGO GUIDELINES
CONCLUSIONS