MRSA Case Study Answers

Prior to class, read the following:

Upshaw-Owens, M., & Bailey, C. A. (2012). Preventing Hospital-Associated Infection: MRSA. MEDSURG Nursing, 21(2), 77-81.

http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0004520/

Briana, a 16 year-old soccer player shows her coach a mysterious sore on her right knee. The sore is warm, painful and red and has been draining pus.

She reports falling on her knee during practice 3 days ago. She continued playing for another 2 hours, and did not wash her knee off until after that. She denies fever, chills, and malaise. The coach refers her to you, the school nurse.

You call her parents and suggest they take her to her personal care provider. Briana visits her family care doctor that afternoon. An I & D (incision and drainage) is performed on the wound. She is started on empiric treatment with po antibiotics. The wound is cultured.

1. What two types of bacteria do you suspect are most likely causing this skin infection? What type of bacteria are they?Staphylococcus aureus and Streptococcus

2. What is meant by ‘empiric treatment’?Empiric treatment refers to the use of broad-spectrum antibiotics to treat an infection before the exact causative species is known. Empiric treatment targets the most likely culprits in an infection.

Briana goes home with her antibiotics. She is taking amoxicillin, an antibiotic in the penicillin class. Her wound does not improve after 3 days of antibiotic use, so she returns to the doctor. By then, the wound culture has come back positive for a MRSA infection.

3. What is MRSA? What makes it resistant?Methicillin-resistant Staphylococcus aureusMRSA bacteria produce an enzyme called beta-lactamase. This enzyme cleaves the beta-lactam ring found in penicillins, deactivating them.

4. Why isn’t Briana getting better, even though she is taking antibiotics?Amoxicillin is an antibiotic in the penicillin class. Thus, it has a beta-lactam ring that is deactivated by MRSA.

5. What are some of the diseases and conditions caused by S. aureus?6. What characteristics of the S. aureus bacterium increase its virulence?7. What body fluids may contain MRSA?8. What are some risk factors for CA-MRSA colonization?9. S. aureus colonizes 32% of the population, and MRSA colonizes 0.8% of the population. What is

colonization?

10. Name some strategies for reducing the spread of MRSA in the hospital setting. 11. How can patients with MRSA be decolonized?12. Why is MRSA such a big deal?