MRSA: A Doctor s Nightmare

1. MRSA: A Doctor�s Nightmare? John Verstraete D.O. Mid-America Infectious Disease Consultants

2. MRSA Initially emerged in the 1960�s Major pathogen by 1980 Currently 30% of Staph aureus in hospitals is Methicillin-resistant Community carriage is 4-10% and growing.

3. Classical Risk Factors for MRSA Prior antibiotics Penicillins Cephalosporins aminoglycosides Prolonged hospitalization (nursing homes) Underlying disease (COPD) Advanced age Invasive procedures

4. Community Acquired MRSA Often do not fall into the classical risk groups Several other antibiotic options often still show sensitivity Involved healthy individuals Spider bite?

5. Transmission of MRSA Patients are commonly colonized in the nares or respiratory tract or on their skin Transmission is typically by direct contact with colonized or infected persons

6. Microbiology of MRSA Caused by changes in penicillin binding proteins Generally resistant to all B-lactam antibiotics May be resistant to TMP/Sulfa, Tetracyclines, Quinolones Vancomycin resistance has been reported (VISA, GISA)

7. Clinical Manifestations of MRSA Infection Skin/soft tissue infection Pneumonia Endocarditis Bone infection Line infection

8. CA-MRSA Recurrent skin infections

9. Colonization of the Newborn Uterus and contents are normally sterile and remain so until just before birth. Breaking of fetal membrane exposes the infant; all subsequent handling and feeding continue to introduce what will be later become normal flora.

10. Resident Flora Includes bacteria, fungi, protozoa, viruses and arthropods Most areas of the body in contact with the outside environment harbor resident microbes; large intestine has the highest numbers of bacteria. Internal organs and tissues and fluids are microbe-free. Bacterial flora benefit host by preventing overgrowth of harmful microbes � microbial antagonism.

11. Staphylococcus aureus Gram-positive bacterium that frequently colonizes the nose and skin of healthy persons Leading cause of skin & soft tissue infections (SSTI) Abscesses (boils), furuncles, and cellulitis

12. Methicillin-resistant Staphylococcus aureus (MRSA) Resistant to all beta-lactam antibiotics Note: methicillin no longer used clinically or in lab�look for oxacillin or nafcillin resistance Increasingly important cause of healthcare-associated infections since the 1960s For 20 yrs, MRSA infections mostly associated with healthcare settings

13. Here we have plotted theprevalenceo MRSA, MR CNS and VRE reported from nosocomial infections. These pathogens account for over half of the bloodstream infections among ICU patients. In 1999 the prevalence of MRSA has broken the 50% mark for ICU patients, and VRE has reached 25%.Here we have plotted theprevalenceo MRSA, MR CNS and VRE reported from nosocomial infections. These pathogens account for over half of the bloodstream infections among ICU patients. In 1999 the prevalence of MRSA has broken the 50% mark for ICU patients, and VRE has reached 25%.

14. Emergence of MRSA in the Community 1990s: Strains of MRSA distinct from those already established in healthcare settings (HA-MRSA) emerged worldwide as a cause of infection among otherwise healthy adults and children in the community (CA-MRSA) Genetic characteristics of these strains suggested they originated in the community, and did not spread from hospitals

15. Original Case Definition for CA-MRSA A positive culture for MRSA within 48 hours of admission No history of hospitalization, surgery, residence in a long-term care facility, or dialysis within the prior year No indwelling or percutaneous medical devices No history of MRSA infection or colonization

16. Distinctions Between CA-MRSA and HA-MRSA Now Blurring Strain characteristics (genotypes & susceptibility profiles) are becoming less closely linked to epidemiologic case classifications (CA-MRSA vs. HA-MRSA) Movement of �community strains� into healthcare settings Emerging resistance to non-beta-lactam agents in �community strains�

17. MRSA Was the Most Commonly Identified Cause of Purulent SSTIs Among Adult ED Patients

18. Factors Facilitating MRSA Transmission (5 �C�s) Contact Crowding Contaminated items Compromised skin integrity Cleanliness (lack thereof)

19. Persons at Risk for CA-MRSA Household contacts of patient with proven CA-MRSA Day-care center contacts of hospitalized patients with MRSA infection Incarcerated persons Soldiers Men who have sex with men Drug users Athletes Students Children

20. Persons at Risk for CA-MRSA (cont.) Pacific Islanders Native Americans Persons with a previous CA-MRSA infection

21. It�s Everywhere

22. Clinical Considerations SSTI MRSA Obtain material for culture I&D should be routine for all purulent skin lesions No data to suggest molecular typing or toxin-testing should guide management

23. Clinical Management of SSTI MRSA Incision & drainage is the mainstay Antimicrobial therapy sometimes prudent Use susceptibility data to guide treatment Avoid fluoroquinolones & macrolides Nasal culture not typically beneficial Patient education is critical! Maintain adequate follow-up

24. Empiric Antibiotic: Considerations Severity & rapidity of progression, or cellulitis Signs and symptoms of systemic illness Patient co-morbidities or immune suppression e.g., diabetes mellitus, neoplastic disease, HIV infection Extremes of patient age Location of the abscess area difficult to drain or associated with septic phlebitis of major vessels (e.g., central face) Lack of response to initial treatment with I & D alone

25. Options for Outpatient Rx of MRSA SSTIs

26. Infection Control in the Clinic(open or draining SSTI) Wear gloves when providing care for patients Remove gloves before leaving the patient's room and wash hands or use alcohol-based hand sanitizer immediately. Do not touch potentially contaminated environmental surfaces or items in the patient's room after glove removal and hand washing, to avoid transfer of microorganisms to other patients and environments.

27. Infection Control in the Clinic(open or draining SSTI) cont. Wear a gown (if there will be substantial contact with the patient�s wound) Remove the gown before leaving the examination room Limit the movement and transport of the patient Ensure that patient-care items and potentially contaminated surfaces are cleaned and disinfected after use. Avoid wearing ties Clean stethoscope after each patient

28. Key Prevention Messages for Patients and their Close Contacts Keep wounds that are draining covered with clean, dry, bandages Clean hands regularly with soap and water or alcohol-based hand gel (if hands are not visibly soiled). Always clean hands immediately after touching infected skin or any item that has come in direct contact with a draining wound Maintain good general hygiene with regular bathing Do not share items that may become contaminated with wound drainage, such as towels, clothing, bedding, bar soap, razors, and athletic equipment that touches the skin

29. Key Prevention Messages for Patients and their Close Contacts (cont.) Launder clothing that has come in contact with wound drainage after each use and dry thoroughly. If you are not able to keep your wound covered with a clean, dry bandage at all times, do not participate in activities where you have skin to skin contact with other persons (such as athletic activities) until your wound is healed. Clean equipment and other environmental surfaces with which multiple individuals have bare skin contact with an over the counter detergent/disinfectant that specifies Staphylococcus aureus on the product label and is suitable for the type of surface being cleaned. Isolation is not practical

30. Case 1 87 y.o. white male presents with complaints of a wound on his foot PMH COPD DM MEDS Albuterol Inhaler prn, Insulin, Multi- vitamin Allergies PCN-rash SH- remote tobacco, denies ETOH, lives in a Nursing home FH- positive for DM in mother Temp 102.5 120 28 140/90 88%

31. Case 1 cont. Gen A & O x 3 HEENT- PERRLA, EOMI Neck- supple, No LAD, No JVD H-tacky L- CTA Abd- Soft NT ND Ext- Marked erythema of Left foot with ulceration WBC-13,000 with an increased number of PMNs

32. An infected ulceration plantar to the fifth metatarsal head. This ulceration could be probed to the bone, and a deep space infection was present. The patient was taken to surgery to drain the underlying abscess.

33. Foot infection. Radiographs of the foot demonstrate the development of osteomyelitis. The cuboid, anterior portion of the calcaneus, base of the fifth metatarsal, and base of the fourth metatarsal were all involved and required debridement.

34. Foot infection. Lateral view of foot demonstrating osteomyelitis

35. Most Likely Infecting bacteria Staph aureus Strept Gram Negatives (Pseudomonas) Anerobes

36. Due to pts allergy pt was started on IV Cefepime

37. Despite minimal improvement, on day 3 it was noted that patient�s culture was positive for MRSA. Patient was immediately changed to Vancomycin.

38. Pt was transferred to the skilled unit to complete 6 weeks of IV vancomycin.

39. Diabetic Foot Infection Prevelance An estimated 15% of people with diabetes in the United States will develop a foot ulcer that may have a potentially serious complication Microbiology The predominant pathogens in DFI are aerobic gram positive cocci Gram negative rods, and anaerobes. ?MRSA

40. Treatment of MRSA Vancomycin is the drug of choice Zyvox (Linezolid) IV or oral an alternative Synercid (Quinupristin/Dalfopristin) IV only Cubicin (Daptomycin) is another IV alternative (Doesn�t cover pulmonary infections) Mild MRSA infections TMP/Sulfa Tetracyclines Rifampin Quinolones Removal of foreign bodies

41. Case 2 JB is a previously healthy 49 year old white male He cut his foot on a clean piece of aluminum that he was installing around a window frame of his house in late April He received local wound care only and the wound appeared to heal and crust over Approximately 1 week later, the wound began to develop erythema, swelling, & pain; Ffevers or chills

42. Case Presentation The wound later spontaneously opened and purulent material began to drain from it The swelling and erythema began to spread up the leg There was increased pain with movement of the leg or with ambulation Pt. presented to a local ED

43. Case Presentation Afebrile upon presentation (T=98.9) ESR 77; CRP 29.99, WBC=11,000 Plain films ? marked soft tissue swelling but no evidence of osteo, fracture, or foreign body Pt was admitted. Seen by podiatry and thought to have an abscess Underwent I & D; cultures submitted

44. Case Presentation Treated with cefazolin, elevation, W?D dressings, with a slow response Culture data then forthcoming ID consult was obtained

45. Culture Results �

46. Infectious Disease� Conclusions Foot soft tissue infection/abscess secondary to MRSA � no evidence of bony involvement � S/P I&D Cefazolin was changed to vancomycin with cont. tx for 2 weeks Of interest was that the infection was community-acquired. Pt had no risk factors for MRSA nor did any of his immediate family.

47. Resistant Gram Positive Organisms Who�s Winning?

48. Case presentation 33 y/o male nurse admitted to the hospital because of fever and increasing pain in the right leg On physical exam he appeared toxic and there was erythema over the medial malleolus Patient believed he had been bitten by a spider The next day the leg doubled in size, he is lethargic and c/o severe pain.

50. Differential diagnosis Staph or strep Grp A Strept cellulitis Necrotizing fasciitis Clostridial myonecrosis Synergistic necrotizing cellulitis Vibrio vulnificus Capnocytophaga canimorsus (DF-2)

51. MRSA Hospital-acquired Infections

52. Pathogenesis MRSA colonization can lead to infection Increased colonization seen in the elderly, and debilitated patients Increased colonization also seen in: -Hospital workers - Dialysis pts -Newborns -IVDA pts -Pts with dermatitis - IDDM pts -Previous exposure to ABX�s

53. Modes of Transmission Principle mode of spread is pt. to pt. via transiently colonized HANDS of hospital personnel Acquired from direct pt. contact or handling contaminated equipment (stethoscopes, thermometers) Airborne transmission ? Chronic-care facilities are the major reservoir

54. Virulence MRSA strains are NOT more virulent than MSSA MRSA strains are NOT less virulent than MSSA MRSA strains are NOT more contagious Increase risk of infection: Long-term colonization Underlying host factors Increasing disability

55. Treatment of MRSA Vancomycin is drug of choice If vancomycin allergic, TMP/SMX + rifampin, clindamycin, doxycycline, linezolid, synercid, daptomycin Vancomycin is ineffective in eradicating the carrier state

56. Guidelines for Infection Control Identify the pts and place on contact isolation HANDWASHING ;Change gloves between patients!!! Alcohol hand rub liquid Keep BP cuff, stethoscopes, etc. in pt�s room Do not transfer instruments from pt to pt unless disinfect between pts i.e. scissors

57. Preventing Antimicrobial Resistance in Hospitals Prevent Infection Use Antimicrobials Wisely 1. Seek expert input 2. Get the catheters out 3. Know you antibiogram Eradicate Infection 4. Obtain cultures 5. Know when to say �no� to Vanco 6. Treat to cure 7. Less is best 8. Don�t treat colonization 9. Quit when you are ahead

58. Use Antimicrobials Wisely Less is often best Target the pathogen and only the pathogen Use/switch ASAP to an effective narrow spectrum regimen

59. Don�t treat pseudobacteremias Coag-negative staphylococci Patient risk factors? Prosthetic devices? Check # positive / # ordered Compare antibiograms/ fingerprints

60. Use Antimicrobials Wisely Don�t treat colonization Treat pneumonia, not the endotracheal tube Treat urinary tract infection, not the Foley catheter Treat bacteremia, not the catheter tip Treat the bone infection, not the skin flora

61. Use Antimicrobials Wisely Quit when you are ahead Stop antimicrobials When infection is not diagnosed When infection is unlikely When cultures are negative

62. Prevent Transmission Isolate the pathogen Use standard infection control precautions Contain infectious body fluids Airborne/droplet/contact precautions When in doubt use common sense

63. Prudence use of Antibiotics Antibiotics exert tremendous selection pressure for organisms to develop resistance

64. Zyvox Bactrim Doxycycline Clindamycin (Risk for C-diff) Levaquin? Oral Options for MRSA

65. Decolonization? Effectiveness in preventing disease not clear Resistance is a concern May be reasonable to administer (after optimizing basic strategies): Patient with recurrent infections Ongoing transmission in a closely-associated cohort (e.g., household) Appropriate regimens (agents and schedules) not established for community settings