Introduction
Enterococci are bacteria (germs) frequently found in the environment, such as in soil and water, and are typically found in the female genital tract and the human intestines. These microorganisms may cause infections. The enterococci bacteria are always coming up with novel strategies to evade the antibiotics used to treat the diseases they cause. Antibiotic resistance arises when bacteria become resistant to the antibiotics that kill them. These microorganisms become Vancomycin-resistant Enterococci (VRE) if they grow resistant to Vancomycin, an antibiotic used to treat some drug-resistant illnesses.
How Does Enterococcus Become Resistant to Vancomycin?
To resist various antibiotics, including aminoglycosides, B-lactams, tetracyclines, quinolones, and Vancomycin, enterococci have developed several resistance mechanisms (glycopeptide). They naturally have penicillin-binding proteins with low beta-lactam affinities, are capable of producing beta-lactamases, and have reduced cellular permeability to several of them. Vancomycin-resistant bacteria, in particular, changes in the production of the peptidoglycan that makes up the bacterial cell wall cause enterococcus resistance. The D-Ala-D-Ala terminus of the protein precursors to peptidoglycan is where Vancomycin typically binds. When this terminal is altered to D-Ala-D-lactate, Vancomycin binds with less affinity, which leads to the development of resistance. The genotypes VanA through VanG, in alphabetical order, are used to code this. The chromosomal phenotypes VanD and VanC are significantly less prevalent than the plasmid-based VanA and VanB genotypes, which are by far the most prevalent.
Who Is at Risk for VRE Infection?
VRE infections occur more frequently in those who:
-
Are receiving long-term antibiotic treatment while they are hospitalized.
-
Are older.
-
Have chronic illnesses or compromised immune systems.
-
Have previously received long-term treatment with Vancomycin or another antibiotic.
-
Have been hospitalized in intensive care units (ICUs).
-
Have worked in a transplant or cancer unit.
-
Have undergone major surgery.
-
Have catheters to drain urine or long-lasting intravenous (IV) catheters.
What Are the Symptoms of VRE Infection?
Enterococcus causes various clinical manifestations. Some of the clinical manifestations present are as follows.
-
Bacteriuria - Enterococcus can bring on numerous clinical disorders. Although it is becoming increasingly obvious that many of these instances are caused by colonization rather than infection, bacteriuria is still the most frequent clinical manifestation. Bacteremia without endocarditis is the second most common cause of infection, followed by endocarditis.
-
Urinary Tract Infection (UTI) - UTIs linked to healthcare are usually noted as having enterococcus as one of the three most likely causes of both simple and complex UTIs. E. faecalis makes up the majority, despite E. faecium being the predominant isolate with Vancomycin resistance. It frequently involves equipment and indwelling urinary catheters.
-
Intra-Abdominal and Pelvis Infections - Vancomycin-resistant enterococcus is frequently isolated from pelvic and intra-abdominal infections as commensals (an organism that feeds on food found in the host's internal or external environment without developing an intimate relationship with the host, such as by consuming its tissues). Peritonitis, wounds, and abscesses are among the common infections. They frequently form part of a multi-organism infection with gram-negative or anaerobic pathogens. However, enterococcal bacteremia is frequently linked to intra-abdominal and pelvic abscesses, necessitating antibiotic treatment for enterococcus.
-
Bacteremia - Vancomycin-resistant enterococcus frequently manifests as bacteremia, which can be fatal. Intravascular or urinary catheters frequently result in nosocomial bacteremic infections. Bacteremia in the general population is frequently brought on by translocation from the GI (gastrointestinal) and genitourinary (GU) tract. Increased mortality is linked to E. faecium in the bloodstream, most likely because of the higher resistance levels.
-
Infective Endocarditis - The second most typical cause of infective endocarditis is enterococci. Central lines, GI or GU tracts following surgery, damaged mitral or aortic valve infections, or liver transplants are common sources. E. faecalis is frequently the cause of community-acquired endocarditis in people without known risk factors. Clinically, they exhibit constitutional symptoms and subacute fevers. Fever or a new murmur are typical indicators of infection. As with other etiologies, typical endocarditis stigmata, including petechiae, Osler nodes, and Roth spots, are uncommon and often accompany subacute illness rather than acute infection.
-
Other Sites of Infections - Enterococcus can occasionally cause Vancomycin-resistant central nervous system infections (CNS). When it does, E. faecium generally causes it rather than E. faecalis. Neurosurgical procedures like shunts frequently result in infection. Like most CNS infections, fevers and altered mental status are frequent symptoms. Vancomycin-resistant as a component of microbial infection, enterococcus is also seen in skin infections. They are present in soft tissue abscesses, osteomyelitis, and decubitus ulcers. Finally, pneumonia brought on by enterococci is quite uncommon. When it happens, it is typically diagnosed as VAP (ventilator-associated pneumonia) in severely immunosuppressed and weakened patients who have previously taken broad-spectrum antibiotics.
How Is VRE Infection Evaluated?
Assessment for Vancomycin resistance by identifying the underlying infectious illness process will be the first step in treating enterococcus. The next step is to assess each potential infection source. Before giving empiric antibiotics, samples from the possible source will be sent for regular culturing to identify the particular species and medication susceptibilities. Fosfomycin, Daptomycin, Nitrofurantoin, and Chloramphenicol sensitivity tests are done as clinically necessary because they are not always standard in labs.
How Is VRE InfectionTreated?
Antibiotics other than Vancomycin are typically used to treat VRE infections when they do occur. Healthcare professionals will send a sample (commonly referred to as a culture) to the lab and test any bacteria that grow against a set of antibiotics to discover which are active against the germ. This will help them decide on the appropriate antibiotic to treat a specific ailment. The healthcare professional will then decide on an antibiotic based on its activity and additional variables, including possible side effects or drug interactions. Being colonized refers to how some people carry the VRE infection on their bodies without experiencing any symptoms. Therefore, antibiotics are not necessary for colonized individuals.
What Are the Complications Of VRE Infection?
The complications that can occur in VRE infection are:
-
Endocarditis (a heart valve infection that affects the heart's inner lining).
-
Colitis (colonic inflammation that is frequently auto-immune or infectious).
-
Osteomyelitis (infection-induced bone inflammation that typically affects the legs, arms, or spine).
-
Sepsis (occurs when the body reacts incorrectly to an infection).
-
Pneumonia (an infection that causes swelling and fluid buildup in the air sacs in one or both lungs).
How Can a VRE Infection Be Prevented?
The preventive measures that can safeguard from VRE infections are:
-
Avoiding illness and transmitting infectious agents by keeping the hands clean. Patients and caregivers should wash their hands often with soap, water, or alcohol-based hand sanitizer.
- Before handling medical devices or tending to wounds.
- Before preparing food.
- After using the restroom.
-
Regularly cleaning any potential VRE-infested sections of the house, like the bathrooms.
-
Putting on gloves while handling objects like bandages from infected wounds or stool (poop) that may contain VRE.
-
Let medical professionals know if there is a prior VRE infection so that proper measures can be taken to stop the spread of the infection.
Conclusion
Although preventative steps have been taken, VRE is still an issue in many hospitals. Short-term findings demonstrate that administering antibiotics cautiously and continued adherence to infection control procedures, particularly in high-risk patients, is essential for preventing VRE.
