Guideline for the prevention of health care-associated infection in urological practice in Japan

Authors

  • Ryoichi Hamasuna,

    Corresponding author
    1. Department of Urology, University of Occupational and Environmental Health, Kitakyushu,
    2. Japanese Research Group for UTI,
    3. Committee Member, The Drafting Committee for Infection Control Guides in the Urological Field,
      Ryoichi Hamasuna M.D., Ph.D., Department of Urology, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu, Fukuoka 807-8555, Japan. Email: hamaryo@med.uoeh-u.ac.jp
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  • Satoshi Takahashi,

    1. Department of Urology, Sapporo Medical University School of Medicine, Sapporo,
    2. Japanese Research Group for UTI,
    3. Committee Member, The Drafting Committee for Infection Control Guides in the Urological Field,
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  • Shingo Yamamoto,

    1. Department of Urology, Hyogo College of Medicine, Nishinomiya,
    2. Japanese Research Group for UTI,
    3. Committee Member, The Drafting Committee for Infection Control Guides in the Urological Field,
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  • Soichi Arakawa,

    1. Division of Integrated Medical Education, Department of Social/Community Medical and Health Science, Kobe University Graduate School of Medicine, Kobe,
    2. Japanese Research Group for UTI,
    3. Committee Member, The Drafting Committee for Infection Control Guides in the Urological Field,
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  • Hitoshi Yanaihara,

    1. Department of Urology, Saitama Medical University, Moroyama,
    2. Recommendation Committee from the Japanese Society of Endourology and ESWL and
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  • Satoru Ishikawa,

    1. Department of Urology, Hitachi Ltd. Hitachi General Hospital, Hitachi, Japan,
    2. Recommendation Committee from the Japanese Society of Endourology and ESWL and
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  • Tetsuro Matsumoto

    1. Department of Urology, University of Occupational and Environmental Health, Kitakyushu,
    2. Japanese Research Group for UTI,
    3. Chairman, The Drafting Committee for Infection Control Guides in the Urological Field
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Ryoichi Hamasuna M.D., Ph.D., Department of Urology, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu, Fukuoka 807-8555, Japan. Email: hamaryo@med.uoeh-u.ac.jp

Abstract

For developing the Japanese guideline for the prevention of health care-associated infection in urological practice, we surveyed the literature including standard precautions, environmental considerations in both the inpatient and outpatient settings, the management of urinary catheters, endoscopy techniques, and the disinfection and sterilization of instruments used in endoscopies and related procedures. The concept of this guideline is to show the minimum precautions that urologists and other medical professionals should observe when they work in the urological field. Standard precautions based on hand hygiene and the use of personal protective equipment should be observed in both the inpatient and outpatient settings. In the inpatient setting, the management of the toilet is important. Collecting urine should be restricted only when it is necessary to determine a patient's urinary output. The management for urinary catheter and infection are created based on the “European and Asian guidelines on management and prevention of catheter-associated urinary tract infections”. In addition, we propose that nephrostomy should be carried out after maximum barrier precautions have been taken. Urinary catheters are replaced in the event of an occlusion or if there are signs that an occlusion might occur, but the same catheter cannot be left in place for more than 2 months. Regarding the handling of urine containing Mycobacterium tuberculosis, airborne infection countermeasures are unnecessary, except for the laboratory personnel. For the procedures using urological endoscopes, aseptic techniques are recommended. Endoscopes and related devices should be used by sterilization or high-level disinfection, but formaldehyde gas cannot be used.

Introduction

The basic protocols for infection control in any health care setting are compliance with “standard precautions”.1 Standard precautions are meant to reduce the risk of transmission of blood-borne and other pathogens from both recognized and unrecognized sources. Patient blood and all other body fluids, with the exception of sweat, including their secretions, such as excretions, mucous membranes and damaged skin, should be treated as potential sources of infection. The objectives of this policy are to: (i) prevent the spread of infection between patients by medical staff; (ii) safely guard medical staff against pathogens from infected or symptomatic patients; and (iii) reduce the number of accidental needle sticks and accidental exposures to blood and body fluids. In addition to the standard precautions, precautionary measures against contact infections are especially important in urology. Although wound treatment, secretion disposal and handling of infected urine are common procedures, it is important to observe the following at all times: (i) appropriate hand hygiene, including washing hands or using an alcohol-based hand gel before and after the care of any patient; (ii) always wear gloves when dealing with a wounded area or catheter, regardless of whether or not the patient is infectious; and (iii) the use of personal protective equipment (PPE), including wearing gloves, a gown or other protective items, when in direct contact with an infectious patient or interacting with items in the hospital room of an infectious patient.

Although cystourethroscopes, which are rigid or flexible, are used in urology, there are no set guidelines for their disinfection or sterilization. High-level disinfection, autoclaving and ethylene oxide gas (EOG) sterilization are all common methods. The conventional means of high-level disinfection for cystourethroscopes has been immersion in glutaral (glutaraldehyde). However, methods such as the automatic washing of flexible cystourethroscopes using peracetic acid are beginning to gain popularity. In addition, low-temperature plasma sterilization can also be used on rigid cystourethroscopes and some flexible cystourethroscopes.

We surveyed the literature regarding prevention of health care-associated infection in urological practice, including standard precautions, environmental considerations in both the inpatient and outpatient settings, the management of urinary catheters, endoscopy techniques, and the disinfection and sterilization of instruments used in endoscopies and related procedures. However, we could not find sufficient evidence regarding these topics, as they specifically pertain to urology. In the present guideline, we describe the minimum precautions that urologists and other medical professionals should observe when they work in the urological field. The present guideline for the prevention of health care-associated infection in urological practice is partially a result of numerous discussions of the working group in the Japanese Society of Urinary Tract Infection Cooperative Study Group. The results of these discussions were systematically organized by the Japanese Urological Association. In addition, we consulted with the Japanese Society of Endourology and Extracorporeal Shock Wave Lithotripsy (ESWL) to make the guideline commonly available.

The level of advisability and strength of the scientific evidence for papers considered in this guideline follow the classifications (Tables 1 and 2) described in “The guidelines for prevention of perioperative infections in the urological field2 (Japanese Urological Association)”.

Table 1. Table 1 Levels of advisability
AdvisabilityDescription
AStrongly recommended
BGenerally recommended
CAt your own discretion
Table 2. Table 2 Scientific paper rankings
LevelDescription
IExperimental evidence from at least one randomized controlled trial or meta-analysis
IIExperimental evidence from non-randomized controlled trial comparative studies or cohort studies
IIICase-series study or expert opinion

I. Infection control in the urological ward

Standard precautions for infection control in the urological ward1,3

  • 1The goal of infection control in inpatient urology is to maintain compliance with standard precautions (AI).
  • 2The basics of standard precautions are hand hygiene and the use of PPE (AIII).
  • 3In medical practice, hand hygiene through sanitary hand washing or rubbing with alcohol-based hand gels (fast-drying alcohol-based sanitizer) is required before and after all procedures (AII).
  • 4Hand hygiene management is required after the use of PPE (BIII).

Hospital room management1,4–6

  • 1Private rooms are preferable if possible (BIII).
  • 2Exercise private room management for patients with a specific infectious disease (isolation), severely immunocompromised patients (reverse isolation) and severely ill patients (BII).
  • 3Private rooms are standard for patients who have had resistant bacteria isolated from open areas, such as a surgical wound site or sputum (BII).
  • 4Do not allow patients with a high risk of infection to share rooms with patients who have had resistant bacteria isolated from their urine or feces, and who are experiencing urinary or fecal incontinence (BIII).
  • 5Examine infectious patients last on rounds and take precautionary measures to prevent the spread of contact infections (BIII).
  • 6Ensure that patients from whom resistant bacteria have been isolated observe strict hand washing and hand sanitation. Instruct them to remain in their hospital room except when necessary (BIII).

Waste management (urination management)

  • 1The management of urine is extremely important in inpatient urology (AII).
  • 2Do not change slippers in the toilet (BIII).
  • 3Rinse out used bedpans while wearing gloves. Wash bedpans using an automatic washing machine, such as a bedpan washer, or disinfect by soaking in 0.1% amphoteric surfactant or a 0.1% solution of hypochlorous acid for 30 min7 (BII).
  • 4Collect urine only when necessary (BIII).

Because there are many elderly patients and patients with urinary catheters, urinary tract infections (UTI) or dysuria in inpatient urology, urinary waste management is extremely important for controlling infection.8–11 Special care is required, because bacteria that thrive in watery environments, such as Pseudomonas aeruginosa, can cross-infect through urinals, cleaning brushes, urine collection vessels and so on.5,12

Clean toilets hygienically; toilets should be wall-mounted with a space underneath to allow for easy cleaning and washing. Do not change slippers, as it might lead to the spread of infection via hands.

Collecting urine should be restricted only to instances in which it is necessary to determine a patient's urinary output, including creatinine clearance measurement. If patients or medical staff use a urine collection vessel or automatic urinary output measuring device, their hands should be disinfected after use.

Urinary catheter management and infection

(1) Urinary catheter management

  • 1Bacteriuria is present in nearly 100% of catheterized patients 30 days after insertion (AII).
  • 2Even if the area around the urethral meatus is washed and disinfected, the frequency of bacteriuria does not decrease (AI).
  • 3Carry out urinary catheter insertion aseptically using sterilized equipment (AII).
  • 4Train all medical staff in the proper insertion techniques and in the possible complications regarding catheter insertion (AII).
  • 5As much as possible, maintain the integrity of the series of junctions of the catheter, urine tube and drainage bag in closed urinary catheters; collect urine samples from the urine sample port (AIII).
  • 6In order to prevent urinary reflux, place the drainage bag in a position lower than the patient's bladder (AIII).
  • 7Do not place drainage bags directly on the floor (AIII).
  • 8Catheters with hydrophilic silver coatings or antibacterial coatings are thought to be effective only for short-term use in settings such as the intensive-care unit (ICU) (BII).
  • 9The use of prophylactic antimicrobials in long-term urinary catheter patients is not recommended (AII).
  • 10The optimal time for catheter replacement varies from patient-to-patient. Replace the catheter in the event of an occlusion or if there are signs that an occlusion might occur. In general, do not leave the same catheter in place for more than 2 months (BIII).

Approximately 40% of all nosocomial infections are UTI, approximately 10–20% of which are caused by urogenital surgeries or procedures, and approximately 80% of which originate from urinary catheters. Thus, urinary catheter management is extremely important for controlling infections in inpatient urology.10,11 This section was created based on the “European and Asian guidelines on management and prevention of catheter-associated urinary tract infections.”11

Bacteriuria is present in almost 100% of patients with open urinary catheters within 4 days of insertion.8,9 Although the closed urinary catheter system dramatically reduces the occurrence of bacteriuria, it is still present in nearly 100% of patients 30 days after insertion.9 Bacteria can enter the urinary tract through the inside or outside of the urinary catheter. In a closed system, bacteria can enter into the urinary tract during the removal of the catheter and drainage tube, or through the opening of the urine collection bag. However, in long-term catheterization, bacteria enter along the outside of the tube, eventually causing bacteriuria. Even periodically cleaning or sterilizing of the area around the urethral meatus does not decrease the frequency of bacteriuria.13

Practice proper hand hygiene and wear gloves when inserting a catheter. Sterilize the area around the urethral meatus using 0.02% benzethonium chloride or 10% povidone-iodine. Use a sufficient amount of sterile lubricating jelly. Use the smallest possible diameter catheter and leave it inserted for the shortest amount of time possible. Catheters with hydrophilic silver coatings or antibacterial coatings are thought to be effective only for short-term use in settings such as the ICU. The use of prophylactic antimicrobials is not recommended.

As much as possible, maintain the integrity of the series of junctions of the catheter, urine tube and drainage bag in the closed urinary catheter system. Collect urine samples from the urine sample port. In order to prevent urinary reflux, place the drainage bag in a position lower than the patient's bladder, but do not place drainage bags directly on the floor. In order to prevent contamination of the drainage port, do not allow direct contact with the floor or urine collection vessels. There is no evidence that bladder irrigation reduces the frequency of bacteriuria.8 Use a sterile syringe and sterile physiological saline when carrying out bladder irrigation. In order to prevent the contamination of clothing, medical staff should wear a plastic apron and gloves. In cases where frequent bladder irrigation is necessary, it is preferable to use a three-way bladder irrigation catheter.

There is not currently a consensus on the periodic replacement of catheters.14 In general, replace the catheter in the event of an occlusion, or if there are signs that an occlusion might occur.8,10,11 In cases of long-term catheterization, it is generally recommended that catheters be replaced once every 1–2 months, even if no occlusions occur. Ordinarily, do not leave the same catheter in place for more than 2 months.

(2) Bladder irrigation8–11,15

  • 1The hygienic operation of the junction between the urinary catheter and the urine collection bag is extremely important in closed continuous bladder irrigation (BIII).
  • 2Open bladder irrigation to treat cloudy urine does not decrease the frequency of fever or urinary catheter occlusion (BIII).
  • 3Bladder irrigation with antimicrobials does not decrease the frequency of UTI (AII).
  • 4Bladder irrigation using antiseptic agents carries the danger of exposing mucous membranes to antiseptic agents. In addition, the efficacy of this irrigation method is unclear (AI).
  • 5The use of sterile physiological saline is preferable for bladder irrigation (AIII).

(3) Cystostomy management16,17

  • 1Although many potential benefits of suprapubic cystostomy over urinary catheter use have been identified, no comparative studies have been carried out to show one method's superiority over the other (CIII).

(4) Nephrostomy management

  • 1A nephrostomy is carried out to temporarily maintain the urinary tract and to allow drainage in cases of percutaneous renal lithotripsy, postrenal renal failure, severe hydronephrosis, pyonephrosis and so on. (AII).
  • 2The nephrostomy should be carried out after maximum barrier precautions have been taken (AIII).
  • 3Prophylactic antimicrobials should be given so that blood concentrations reach their peak level at the time of insertion of nephrostomy (AII).
  • 4The optimal replacement time for nephrostomy catheters differs from person-to-person; replace the catheter in the event of an occlusion, or if there are signs that an occlusion might occur (BIII).

Nephrostomies are carried out to temporarily maintain the urinary tract and to allow drainage in cases of postrenal renal failure, severe hydronephrosis, pyonephrosis, percutaneous renal lithotripsy to treat renal/ureteral stones and so on. The careless management of nephrostomies can easily result in a high probability of bacteremia or sepsis.18 Accurate catheter insertion through the combined use of radioscopy and ultrasound, as well as infection control using maximum barrier precautions, is necessary.19 The use of antimicrobials should be based on the “Japanese guidelines for the prevention of perioperative infections in the urological field2” and given so that blood concentrations reach their peak level at the time of insertion.

The replacement of nephrostomy catheters generally occurs approximately once every 2–4 weeks; however, there is no clear evidence for this established period. Replace the catheters in the event of an occlusion, or if there are signs that an occlusion might occur.8–11 Avoid leaving the same catheter in place for more than 2 months. Bacteriuria is almost inevitable in patients with a long-term nephrostomy, even if the catheter is replaced. If there are no signs of infection in the nephrostomy insertion area, sterilization and dressing of the insertion area are not necessary.

(5) Purple urine bag syndrome

  • 1Purple urine bag syndrome (PUBS) is caused by constipation and UTI.
  • 2The treatment of PUBS with antimicrobial agents is unnecessary. PUBS should be treated as an asymptomatic UTI (AIII).
  • 3In treating PUBS, re-evaluation of the necessity of urinary catheter placement, maintenance of urine volume, bowel movement control and so on is necessary (AIII).

PUBS is the appearance of a purple color in the urine collection bag and tube connecting to the urinary catheter that is caused by either constipation or a UTI.20,21 PUBS should be considered an asymptomatic UTI and the administration of antimicrobials is not necessary. In the event of a febrile infection, treatment should be given.

II. Infection control in outpatient urology and urological procedures

Handling of urine and urinalysis

  • 1Wear disposable gloves when handling urine1,3 (AIII).

Because urine is a body fluid, wear disposable gloves when handling urine according to standard precautions. After urinalysis, dispose of urine in a toilet or other waste disposal apparatus, and dispose of used urinalysis test paper, urinary sediment tubes and so on in a medical waste container.

Infection control in an outpatient setting1,3,5,6

  • 1Always keep standard precautions when carrying out an examination (AII).

One of the unique characteristics of outpatient urology is the large number of opportunities for exposing the environment to urine. Bacteria, including multidrug resistant bacteria, have been isolated from the urine of catheterized patients and patients with a history of hospitalization. Always maintain standard precautions when carrying out examinations. Strictly observe hand-washing or the use of disinfectant hand gel, and wear gloves when handling wounded areas or during catheterization (AII). In addition, be aware that bacteria have been detected on the keyboards and mice of computers used for the electronic chart.22

Contrast study of the lower urinary tract (retrograde urethrography, cystography, voiding cystourethrogram, chain cystography) and urodynamic examinations (cystometry, measurement of urinary flow rate)

  • 1In the examination of the lower urinary tract, the insertion of a urinary catheter using hygienic procedures and sterile instruments is extremely important10,11,23,24 (AIII).

Use sterile instruments and an aseptic technique when injecting the contrast medium for retrograde urethrography. After positioning, disinfect the area around the urethral meatus with 10% povidone-iodine, draw the contrast medium from a sterile cup into a sterile enema tube and inject into the external urethral meatus. Cystography is carried out similarly using the hygienic procedure for urinary catheter insertion. Draw contrast medium from a sterile cup using a syringe and inject through the catheter. In cystometry, insert the pressure-sensing catheter using an aseptic technique and sterile instruments.23,24 Pay attention to the hygienic operation of the sterile physiological saline route and gas tube junction leading into the bladder, and replace these for each patient. Regularly clean and disinfect urinals or urine collection devices for the measurement of urinary flow rate once a day.

Upper urinary tract tests (retrograde pyelography) and insertion of ureteral stents

  • 1The examination of and procedures to the upper urinary tract should maintain maximum barrier precautions if at all possible2 (AIII).

Maximum barrier precautions with aseptic technique and sterile instruments are necessary for urological procedures under radiographic guidance, including the insertion or placement of double J stents and retrograde pyelography (AIII). Prepare a sterile endoscope for ureteral catheter management, disinfect the area around the patient's urethral meatus using 10% povidone-iodine and insert the endoscope. If at all possible, use sterile tubes for perfusion with physiological saline and sterile light source cords. If it is not possible to sterilize these instruments, disinfect them with alcohol swabs or 10% povidone-iodine. Antimicrobial prophylaxis is unnecessary after the insertion of a double J stent; give antimicrobials only if there are signs of infection.2,25

Handling the urine of patients with urinary tract tuberculosis

  • 1Airborne infection countermeasures are unnecessary (AIII).
  • 2Under normal conditions, it is safe to assume that the urine of a patient with urinary tract tuberculosis is scarcely infectious (AIII).
  • 3In environments where urine specimens containing tuberculosis bacilli are centrifuged or concentrated, there is a danger of infection to medical staff.
  • 4Benzalkonium chloride or chlorhexidine gluconate is effective in disinfecting the hands for tuberculosis bacilli (AIII).
  • 5An undiluted solution of disinfectant ethanol and a 1% saponated cresol solution are effective for the disinfection of urine containing tuberculosis bacilli (AIII).

Airborne infection countermeasures are unnecessary for urinary tract tuberculosis, because tuberculosis bacilli spread through airborne infection.26 However, there is a risk of airborne infection to laboratory personnel working in environments where urine specimens containing tuberculosis bacilli are centrifuged or concentrated.27 If a patient is suspected of or diagnosed as having urinary tract tuberculosis, all people in contact the patient should be informed immediately.28 For disinfecting hands, benzalkonium chloride (Welpas, 0.2% w/v benzalkonium chloride, 70% ethanol solution) and chlorhexidine gluconate (Wellup, 0.2% w/v chlorhexidine gluconate, 70% ethanol solution) are effective against tuberculosis bacilli. A 1% saponated cresol solution and disinfectant ethanol (undiluted solution) are strong sterilizing agents and are reported as being as effective against tuberculosis bacilli in urine.

Provisions for the intravesical instillation therapy with bacillus Calmette-Guérin

  • 1Because the bacillus Calmette-Guérin (BCG) vaccine is a freeze-dried preparation of strains of attenuated live bovine tuberculosis bacilli, the possibility of infection is present.
  • 2The intravesical instillation therapy with BCG is contraindicated in immunocompromised patients.
  • 3It is necessary to thoroughly follow standard precautions, such as using masks and gloves, when handling BCG (AIII).
  • 4Before disposal, sterilize the medical instruments used in BCG preparation (such as injection syringes and catheters) by autoclaving, boiling or use of an antiseptic solution, such as 10% hypochlorous acid (AIII).
  • 5After the intravesical instillation therapy with BCG, disinfect the urine before disposal in order to prevent infection (AIII).

The BCG vaccine currently used is a freeze-dried preparation of strains of live bovine tuberculosis bacilli that is infectious to humans. BCG administration in patients with bladder cancer who have not recovered from the damage to mucous membranes after transurethral resection (TUR) or trauma as a result of urethral catheter insertion can develop a disseminated BCG infection, including septicemia.29,30 Therefore, BCG administration is contraindicated in immunocompromised patients. When handling BCG, it is necessary to thoroughly follow standard precautions for handling “infectious” preparations, such as the use of masks and gloves. Before disposal, sterilize the medical instruments used in BCG preparation (such as injection syringes or catheters) by autoclaving, boiling or using an appropriate antiseptic solution, such as 10% hypochlorous acid.

After intravesical instillation therapy with BCG, disinfect urine before disposal. Add a volume equal to half of the urine volume of 10% sodium hypochlorite or household bleach and leave for 15 min before disposal. The results of urine sterilization tests for 107 viable BCG cells after the intravesical instillation showed the following: sodium hypochlorite (Hyporite) is effective at 10% or more of the commercial concentration after 15 min of use; saponated cresol solution is effective at 1% or more of the commercial concentration after 15 min of use; and isopropanol is effective at 33% or more of the commercial concentration after 15 min of use. Sodium hypochlorite is corrosive to metal, discoloring and produces chlorine gas when mixed with acid. However, when considering general use and safety, disposal with 10% sodium hypochlorite is appropriate.

III. Aseptic technique and disinfection/sterilization of urological endoscopes

Aseptic technique of urological endoscopes

  • 1Always use aseptic technique (AIII).
  • 2Use gloves and gowns, and wash hands as necessary for the circumstances (AIII).
  • 3Use sterilized liquids, such as sterile physiological saline, depending on the situation for the irrigation of the urinary tract during urological endoscopy (AIII).

The use of sterile gloves is recommended when inserting a cystourethroscope. Disinfect a wide area around the urethral meatus and cover with a sterile cloth before urological endoscopy. In addition, the use of disposable aprons and other protective garments can prevent droplets from adhering to the operator's clothes. When carrying out an operation using a urological endoscope, wash hands and carry out all maneuvers aseptically while wearing a surgical cap, mask, sterile gown and sterile gloves. For the irrigation fluid, use packaged physiological saline or sterile water for observation, or use a specialized irrigation pack for TUR (physiological saline for saline-compatible ablation apparatuses). Use disposable irrigation circuits. Light cables and charge coupled device (CCD) cameras should preferably undergo high-level disinfection or sterilization before use, though the appropriate procedures might differ depending on instruments.

Disinfection and sterilization of urological endoscopes

  • 1Treat urological endoscopes with high-level or greater disinfection methods (AIII).
  • 2Because urological endoscopes inserted into a sterile area are classified as “critical” in the Spaulding classification system, sterilization is preferable (AIII). For flexible endoscopes, strictly monitored high-level disinfection is currently permitted because of compatibility issue.
  • 3The high-level disinfectants used for urological flexible endoscopes are peracetic acid and glutaral. Automatic machine washing is recommended (BIII).
  • 4Sterilize the appropriate endoscopes by autoclaving. Drying is unnecessary if endoscopes are used directly after sterilization (BIII).
  • 5Sterilize flexible endoscopes when necessary through EOG sterilization or low temperature hydrogen peroxide gas plasma sterilization (CIII).
  • 6Do not use formaldehyde gas for disinfection (AI).

There are currently no evidence-based guidelines for the disinfection and sterilization of urological endoscopes. However, because endoscopes are inserted into a fundamentally sterile area (classified as “critical” in the Spaulding classification system), urological endoscopes should be sterilized or disinfected. Endoscopes used in the urological field include the cystourethroscope, ureteroscope and nephroscope, which are further divided into rigid and flexible scopes. Sterilization techniques are generally classified into high-pressure steam sterilization (autoclaving), EOG sterilization and low temperature hydrogen peroxide gas plasma sterilization.31

It is extremely important to clean the surfaces and channels of endoscopes that are contaminated with body fluids or blood directly after use. Brushing both the suction and clamp channels directly after each examination is recommended. Insufficient cleaning will result in residual protein that solidifies, reducing the efficacy of sterilization techniques.31

All rigid scopes currently sold are autoclavable and should be sterilized by autoclaving. The use of non-autoclavable rigid scopes is not recommended. Autoclaving is a simple, inexpensive and safe sterilization technique. EOG sterilization and low temperature hydrogen peroxide gas plasma sterilization can also be used with rigid scopes. However, EOG sterilization takes a long time for complete sterilization, whereas low temperature hydrogen peroxide gas plasma sterilization is extremely costly.

Flexible scopes can be sterilized by either EOG or low temperature hydrogen peroxide gas plasma sterilization.32 Confirm instrument compatibilities, and follow appropriate procedures for either of these methods. Because moisture can remain in a flexible cystourethroscope for more than 60 h after washing, flush tubes with alcohol, remove as much moisture as possible with an air tube and sterilize after drying.

Currently, the recommended high-level disinfectants for urological flexible endoscopes are peracetic acid and glutaral.33,34 The use of ortho-phthalaldehyde on urological endoscopes is prohibited in Japan based on previous reports of anaphylaxis caused by disinfection with ortho-phthalaldehyde.31,35 Glutaral is the only high-level disinfectant usable in manual washing or sterilizing. However, there are reports of this chemical posing a health hazard to medical staff.36 Even if using automatic machine washing, ensure that proper exhaust facilities are installed and wear a gown, goggles and gloves. Because peracetic acid has a strong, irritating odor, deteriorates quickly on dilution and is costly,37 it should be considered a medicinal agent for use exclusively in automatic machine washing. Although there are no directives regulating the use of peracetic acid, it is preferable to establish sufficient ventilation facilities. Available guidelines regarding the reprocessing of gastrointestinal endoscopes can be applied to urological flexible endoscopes. However, urological endoscopes should be processed just before use and immediately after procedure.

A disinfection container called the “formalin box” has gained popularity and is still used to disinfect urological endoscopes at some facilities. Formaldehyde gas has been reported to pose a health hazard to both patients and medical staff that is impossible to ignore.38 In addition, the efficacy of disinfection by formaldehyde gas is uncertain. For these reasons, in this guideline, the Japanese Urological Association and The Japanese Society of Endourology and ESWL strongly and voluntarily declare a total ban on the use of formaldehyde gas to disinfect urological endoscopes within Japan.

Acknowledgment

We discussed this guideline with Hiroshi Kiyota, Kazushi Tanaka, Kiyohito Ishikawa, Shinya Uehara, Mitsuru Yasuda, Kana Kobayashi, Shin Ito, Tomihiko Yasuhuku, Takehiko Sho and Masahiro Matsumoto at the meeting of Japanese Research Group for UTI.

Ancillary