Question 2

College Answer

Predisposing factors

Previous treatment with anti-microbials (especially vancomycin, cephalosporins and broad-spectrum antibiotics)

Increased length of stay

Renal impairment

Long-term IV access

Enteral tube feeding

Prevalence of VRE colonized patients in the ICU

Resident of long-term care facility 
Decreased staff : patient ratios

Consequences

Potential transmission of resistance to Staph aureus

Determined by site of infection if present (eg UTI, bloodstream including endocarditis and rarely respiratory infection) 
Need for isolation

Management

Specific antibiotics if infected rather than colonized depending on sensitivities (Van A resistant to vancomycin and teicoplanin; Van B sensitive to teicoplanin) – options include linezolid, daptomycin, quinupristin-dalfopristin, tigecycline. 
Probiotics may have a role.

Infection control including isolation, contact precautions and PPE, and general infection control measures including surface and environmental cleaning, antibiotic stewardship, screening of contacts and patient surveillance until swabs are negative.

Precautions should continue on discharge from ICU

Discussion

VRE comes up often in this exam. One should become intimately familiar with its behaviour and temperament.

Risk factors for VRE colonisation:

• Proximity to other VRE patients - especially those with diarrhoea
• Advanced age
• Severe underlying illness
• Inter-hospital transfer
• Nursing home residency
• Extended hospitalization
• Specialized nutritional support
• Central venous catheterization
• Haematologic malignant tumours
• Solid organ allograft
• Chronic haemodialysis
• Antibiotic exposure to vancomycin, third-generation cephalosporins, metronidazole, and any antibiotics with anti-anaerobic activity.
• Exposure to multiple antibiotics
• Prolonged duration of antibiotic therapy

Consequences of VRE colonisation

• Need for isolation
• Potential for clinically significant VRE infection
• Potential for transmission of vancomycin resistance to S.aureus

Management of the colonised patient

• Isolation
• Protective equipment
• Scrupulous attention to cleaning areas where the patient has been
• Surveillance swabs until the patient tests negative

Management of the clinically relevant VRE infection

• Linezolid
• Daptomycin
• Tigecycline

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MacIntyre, C. Raina, et al. "Risk factors for colonization with vancomycin-resistant enterococci in a Melbourne hospital." Infection control and hospital epidemiology 22.10 (2001): 624-629.

Tornieporth, Nadia G., et al. "Risk factors associated with vancomycin-resistant Enterococcus faecium infection or colonization in 145 matched case patients and control patients." Clinical infectious diseases 23.4 (1996): 767-772.

Karki, Surendra, et al. "Prevalence and risk factors for VRE colonisation in a tertiary hospital in Melbourne, Australia: a cross sectional study." Antimicrob Resist Infect Control 1.1 (2012): 31.

DeLisle, Sylvain, and Trish M. Perl. "Vancomycin-resistant enterococci: a road map on how to prevent the emergence and transmission of antimicrobial resistance." Chest journal 123.5_suppl (2003): 504S-518S.

Patel, Robin. "Clinical impact of vancomycin-resistant enterococci." Journal of Antimicrobial Chemotherapy 51.suppl 3 (2003): iii13-iii21.

Noble, W. C., Zarina Virani, and Rosemary GA Cree. "Co-transfer of vancomycin and other resistance genes from Enterococcus faecalis NCTC 12201 to Staphylococcus aureus ." FEMS Microbiology letters93.2 (1992): 195-198.