Q) What is VRE (vancomycin-resistant enterococci)?
A) Enterococci are bacteria that are normally present in the human intestines and female genital tract and are often found in the environment. Management of Enterococci infections in challenging due to its inherent resistance to various classes of antimicrobials. Enterococci resistant to vancomycin are called vancomycin-resistant enterococci (VRE). Most of VRE infections are nosocomial and emergence of VRE strains globally have made treatment of VRE infections very difficult.
Q) What types of infections does VRE cause?
A) It can cause of urinary tract, blood stream, and wound infections.
Q) Are certain people at risk of getting VRE?
A) The following persons are at an increased risk becoming infected with VRE:
Persons who have been previously treated with vancomycin and combinations of other antibiotics such as penicillin and gentamicin.
Persons who are hospitalized, particularly when they receive antibiotic treatment for long periods of time.
Persons with weakened immune systems such as patients in Intensive Care Units, oncology or transplant units.
Persons who have undergone surgical procedures such as abdominal or chest surgery
Persons with medical devices that stay in for some time such as urinary catheters or central intravenous catheters.
Q) How common is VRE?
A) Data reported to the Centers for Disease Control and Prevention during 2004 showed that VRE caused about 1 of every 3 infections in hospital intensive care units. VRE was first reported from Pakistan in 2002. Although population based data of VRE from Pakistan is not available, data from a tertiary care center revealed 9% VRE in their nosocomial isolates.
Q) What is the treatment for VRE?
A) Treatment options of VRE infections are very limited and available only in developed countries. Antimicrobial susceptibility pattern of VRE is determined by laboratory testing. In persons with urinary catheter associated VRE infections, removal of the catheter when it is no longer needed can help getting rid of the infection. People who are colonized (bacteria are present, but have no symptoms of an infection) with VRE do not usually require treatment.
Q) What are the alternative treatment options for VRE that should be tested in the clinical laboratory?
A) Because of limited alternative, chloramphenicol, erythromycin, tetracycline (doxycycline or mineocycline), and rifampin may be tested for VRE.
Q) How is VRE spread?
VRE is usually passed to others by direct contact with skin, stool, urine, or blood of VRE infected or colonized persons. It can also be spread indirectly via the hands of healthcare providers or on contaminated environmental surfaces. VRE is not spread through the air by coughing or sneezing.
Q) How can I prevent the spread of VRE?
A) If you or someone in your household has VRE, the following are some measures to prevent spread of VRE:
Always wash your hands thoroughly after using the bathroom and before preparing food. Clean your hands after close contact with persons who have VRE. Wash with soap and water (particularly when visibly soiled) or clean with alcohol-based hand cleaner.
Frequently clean areas of your home such as your bathroom that may become contaminated with VRE. Use a household disinfectant or a mixture of one-fourth cup bleach and one quart of water to clean those areas and surfaces that are touched frequently.
Wear gloves if you may come in contact with body fluids that may contain VRE, such as stool. Always wash your hands after removing gloves.
Be sure to tell any healthcare providers that you have VRE so that they are aware of your infection. What should I do if I think I have VRE?
Q) What are the aims of VRE Control in the hospital settings?
A) The aims of VRE control in the hospital setting should include the following:
A. Preventing the transmission of VRE:
to residents within the facility,
to staff and visitors of the facility, and
to those outside the facility when residents are transferred;
B. Allowing for admission or readmission of patients with VRE; and
C. Preventing the potential transfer of vancomycin resistance to other gram-positive microorganisms (including S. aureus and S. epidermidis) within the facility and the community.
Q) What Infection Control Practices should be adopted to prevent spread of VRE in hospital setting?
A) Consistent application of sound infection control practices will reduce the spread of many nosocomial pathogens, including VRE. Such practices do not depend on the identification of VRE cases, and should be applied in all patient care situations. Specific practices that should be especially followed when caring for VRE cases include:
1) Hand Washing, Gloves, and Gowns
Antiseptic soap is recommended for hand washing
Staff and visitors should wash hands after any contact with a VRE case prior to leaving the resident’s room.
A resident identified as a VRE case should wash his/her hands after any personal hygiene activities (e.g., toileting) and prior to leaving his/her room for group activities. A resident who cannot wash his/her own hands should be assisted with hand washing in these instances.
Staff should wear gloves when providing care which involves any personal contact (e.g., changing clothes, bathing). In the course of resident care, gloves should be changed before further contact with clean surfaces, the resident, or staff if they have become soiled with potentially infectious material (e.g., stool, urine). After such care, staff should remove gloves and wash hands. Care should be taken to avoid touching environmental surfaces or other residents or staff after caring for a VRE case and prior to washing hands.
Gowns should be worn if the provider’s clothing is likely to have substantial contact with a VRE case in the course of care. Gowns should be removed
2) Environmental Surface Precautions
Rooms of VRE cases should be cleaned daily; frequently touched surfaces (e.g., bed rails, bedside tables, doorknobs) should be cleaned with an EPA-approved hospital grade disinfectant-detergent, in accordance with the manufacturer’s instructions. It should be noted that, although VRE is difficult to treat in the individual, it is not more difficult to eradicate from environmental surfaces than other enterococci or similar bacteria.
Patient-care equipment with which a VRE case has contact should be cleaned and disinfected prior to use on another resident.
Upon discharge or transfer, the room of a VRE case should undergo “terminal cleaning” with an EPA-approved hospital grade disinfectant-detergent.
3) Room Placement
A. VRE case should receive special consideration for room placement within the hospital. The order of preference for room placement is:
A private room;
A room with other resident(s) known to be VRE cases (i.e., cohorting); or
A room with other resident(s) who are not at increased risk for infection (e.g., residents without vascular lines, catheters, stomas, decubiti, or other wounds), and who do not have MRSA infection or colonization.
A resident identified as a VRE case who is incontinent of either urine or feces (regardless of the site of documented infection or colonization) or who is unreliable in personal hygiene should be placed in a private room or cohorted in a room with another VRE case.
A VRE case should never be placed in the same room as a resident with current MRSA infection or colonization
Q) What is the clinical laboratory method for VRE detection?
A) METHOD FOR DETECTING VRE
| Methods | Antibiotic concentration | Inoculum Density | Media | Incubation temperature | Incubation time | Result interpretation |
|---|---|---|---|---|---|---|
| Agar screening method | 6 ug /ml | Adjust inoculum to 0.5% McFarland in 0.9% saline | Streak small area (10-15mm) on Muller Hinton Agar.
|
35oC | Full 24 hours | No growth or 1colony=
Vancomycin susceptible. >1colony vancomycin resistant |
Q) What are the QC strains used in the agar screening method?
A) Entercoccus fecalis ATCC 29212-Vancomycin susceptible.
Entercoccus fecalis ATCC51299-Vancomycin resistant.
CLINICAL MICROBIOLOGY PROCEDURES HANDBOOK — ASM (American Society Manual 2nd edition)