MRSA

Question 1

MRSA?

Answer 1

Methicillin-resistant Staphylococcus aureus (MRSA) was one of the first organisms which highlighted the dangers of hospital-acquired infections.

Question 2

Who should be screened for MRSA?

Answer 2

• All patients awaiting elective admissions (exceptions include day patients having terminations of pregnancy and ophthalmic surgery. Patients admitted to mental health trusts are also excluded)
• from 2011 all emergency admissions will be screened

Question 3

How should a patient be screened for MRSA?

Answer 3

• nasal swab and skin lesions or wounds
• the swab should be wiped around the inside rim of a patient’s nose for 5 seconds
• the microbiology form must be labelled ‘MRSA screen’

Question 4

Suppression of MRSA from a carrier once identified?

Answer 4

• nose: mupirocin 2% in white soft paraffin, tds for 5 days
• skin: chlorhexidine gluconate, od for 5 days. Apply all over but particularly to the axilla, groin and perineum

Question 5

Which antibiotics are commonly used in the treatment of MRSA infections?

Answer 5

• vancomycin
• teicoplanin
• linezolid

Question 6

Some strains may be sensitive to the antibiotics but they should not generally be used alone because resistance may develop:

Answer 6

• rifampicin
• macrolides
• tetracyclines
• aminoglycosides
• clindamycin
• Relatively new antibiotics such as linezolid, quinupristin/dalfopristin combinations and tigecycline have activity against MRSA but should be reserved for resistant cases

Question 7

Interaction of MRSA (green bacteria) with a human white cell. The bacteria shown is strain MRSA252, a leading cause of hospital-associated infections in the United States and United Kingdom.

Answer 7