Can Enterococcus bacteria contaminate a Urinary Analysis (UA)?

From the Guidelines

Yes, Enterococcus bacteria can contaminate a urinary analysis (UA). Enterococcus species are common inhabitants of the gastrointestinal tract and female genital tract, making them frequent contaminants in urine samples, especially when proper collection techniques aren't followed 1. When Enterococcus appears in a UA, clinicians must determine whether it represents true infection or contamination by considering the bacterial count (typically >100,000 CFU/mL suggests infection), presence of symptoms, pyuria (white blood cells in urine), and other urinalysis findings.

Some key points to consider:

• Contamination often occurs during sample collection when bacteria from the surrounding skin or genital area enter the specimen 1.
• To minimize contamination risk, proper collection techniques should be employed, including thorough cleansing of the genital area before collection, using mid-stream catch technique, and ensuring the sample container doesn't touch any surfaces 1.
• If contamination is suspected, a repeat sample using proper collection methods is often recommended to obtain accurate results for appropriate treatment decisions.
• Enterococcus faecalis is one of the common organisms causing recurrent UTIs, along with Escherichia coli, Proteus mirabilis, Klebsiella, and Staphylococcus saprophyticus 1.

Proper collection and handling of urine samples are crucial to prevent contamination and ensure accurate diagnosis and treatment of urinary tract infections. The most recent and highest quality study 1 emphasizes the importance of proper collection techniques and consideration of patient factors to minimize contamination risk and ensure accurate diagnosis.

From the Research

Enterococcus Bacteria Contamination in Urinary Analysis (UA)

• Enterococcus bacteria can contaminate a Urinary Analysis (UA) as they are a common cause of urinary tract infections (UTIs), especially in hospitalized patients 2, 3.
• The presence of Enterococcus species in UA can be due to various factors such as the use of catheterization and broad-spectrum antibiotics, which can lead to the selection and spread of resistant strains 4, 5.
• Studies have shown that Enterococcus species, including vancomycin-resistant Enterococcus (VRE), can cause UTIs and contaminate UA 3, 6.
• The management of UTIs caused by Enterococcus species, including VRE, can be challenging due to the limited therapeutic options available and the presence of underlying comorbidities in patients 2, 3.

Diagnosis and Treatment

• The diagnosis of Enterococcus UTIs can be made by urine culture and susceptibility testing 2, 3.
• Treatment options for Enterococcus UTIs include antibiotics such as ampicillin, nitrofurantoin, fosfomycin, and linezolid, depending on the susceptibility pattern of the isolate 2, 3, 6.
• The use of glycopeptides, such as teicoplanin, may be considered as an alternative for the treatment of UTIs due to Enterococcus species 5.

Prevalence and Resistance

• The prevalence of Enterococcus species in UTIs has been increasing over the years, with a significant rise in the isolation of VRE 3, 5.
• The emergence of resistance to multiple antibiotics, including vancomycin, has become a major concern in the treatment of Enterococcus UTIs 2, 3, 4.
• High-level aminoglycoside resistance among Enterococcus species has also been reported, highlighting the need for a more rational and restricted use of antimicrobials 4.