REALM project updateMRSA and KPC

January 26, 2011

Michael Lin, MD MPHon behalf of REALM co-investigators

REALM update

Outline

1. MRSA surveillancea. Overview and main results

b. Contact precautions analysis

c. NICU analysis

2. KPC surveillance and future directions

REALM update

Aim

• Evaluation of 2007 mandate for MRSA active surveillance among all Illinois hospital ICU and “high risk” patients.

– Is the prevalence of MRSA colonization decreasing after the initiation of state-wide active surveillance?

REALM update

Design

3 year project involving all hospitals in city of Chicago with ≥ 10 ICU beds– Serial point prevalence survey of MRSA

colonization in ICUs (6 times over 3 years)– All ICUs (neonatal, pediatric, and adult)– City of Chicago hospitals – chosen for

feasibility and to limit selection bias– Peds/adults – swabbed in nose and groin;

neonates – nose and umbilicus– All cultures processed in central laboratory

REALM update

Design (cont.)

• All 26 eligible hospitals in Chicago participating

• Timeline:– 1st survey: 2008 (2nd half)– 6th survey: 2011 (1st half)

• We tracked the prevalence (%) of1. MRSA colonization2. CA-MRSA vs. HA-MRSA genotype3. Mupirocin resistance

REALM update

Hospital locations within Chicago

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Results

• Through 5 surveys*, total patients:– Neonates: 1,328– Pediatric: 409– Adult: 2,545

* Survey 5 almost complete. All data involving survey 5 are preliminary.

1 2 3 4 50

2

4

6

8

10

12

14

16

MRSA colonization trend among adult ICU patients

Non-CA-MRSACA-MRSA

Survey

Percent

Trend, P = 0.04

1 2 3 4 50

2

4

6

8

10

12

14

16

MRSA colonization trend among PICU

Non-CA-MRSACA-MRSA

Survey

Percent

Trend, P = 0.41

1 2 3 4 50

2

4

6

8

10

12

14

16

MRSA colonization rate among neonates (NICU)

Non-CA-MRSACA-MRSA

Survey

Percent

Trend, P = 0.33

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Mupirocin resistance

Surveys 1-5 combined

No resistance

Low resistance

High resistance

Adult ICU 93% (261/281) 5% (14/281) 2% (6/281)

Pediatric ICU 90% (17/19) 5% (1/19) 5% (1/19)

Neonatal ICU 100% (62/62) – –

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MRSA trend summary

• Adult ICU MRSA colonization rate may be decreasing over time!– No change for PICU or NICU

• CA-MRSA rates stable

• No significant mupirocin resistance

2005 2006 2007 20080

0.5

1

1.5

2

2.5

3

3.5

MRSA incidence (CDC data, 2005-2008)

Hospital-onset, allHeathcare-associated community onset

Mean Incidence per 10,000 per-

son-yrs

Kallen AJ, JAMA 2010

REALM update

Outline

1. MRSA surveillancea. Overview and main results

b. Contact precautions analysis

c. NICU analysis

2. KPC surveillance and future directions

REALM update

Contact Precautions analysis

• Question – of the patients that are found by our point prevalence survey to be MRSA+, what percent of the patients are in contact precautions?

– Data from surveys 1-2– Presented at 5th SHEA/IDSA/CDC Decennial

International Conference on Healthcare-Associated Infections in Atlanta, 2010

Methods

Admission Surveillance

Point Prevalence Surveillance

• Reported by hospital

• Heterogeneous practice

• Obtained by study, standardized

• Variable timing

• Contact Precautions assessed

Study patient timeline

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Admission screen results

• Hospitals had obtained admission screening cultures for– 95% for adults– 98% for neonates

• MRSA admission prevalence (hospital report)– 9.3% for adults– 1.3% for neonates

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Point prevalence survey results

• Median ICU day for point prevalence survey:– Adults: ICU day 4– Neonates: ICU day 17

• MRSA prevalence (point prevalence survey):– 12.4% of adults

(Hospital-reported admission rate, 9.3%)

– 5.3% of neonates(Hospital-reported admission rate, 1.3%)

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Contact Precautions results

• Contact Precautions for any reason:– 26% of adults– 5% of neonates

• Of patients with hospital-reported admission cultures MRSA +:– 87% of adults in Contact Precautions– 86% of neonates in Contact Precautions

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Contact Precautions results

• Of patients with point prevalence survey cultures MRSA +, Contact Precautions rate:

• 52% (65 / 125) of adults

• 39% (11 / 28) of neonates

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Possible reasons for Contact Precautions deficit

1. Inadequate MRSA surveillance test sensitivity

2. Lag time for admission surveillance results

3. Lag time for initiating Contact Precautions after surveillance results known

4. On-going nosocomial MRSA acquisition

REALM update

Possible reasons for Contact Precautions deficit

1. Inadequate MRSA surveillance test sensitivity

2. Lag time for admission surveillance results

3. Lag time for initiating Contact Precautions after surveillance results known

4. On-going nosocomial MRSA acquisition

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Contact Precautions Summary

• Point prevalence surveys identified a greater proportion of MRSA-colonized ICU patients compared to routine mandated admission screening.

• At a given point in time, about half of MRSA-colonized ICU patients were not in Contact Precautions, despite on-going active surveillance at admission.

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Contact Precautions Conclusion

• Possibilities for improvement:– Increasing test sensitivity (more body sites,

enrichment methods)– Periodic surveillance to detect acquisition

(especially among neonates)

• We do not know if current 50% level of Contact Precautions is sufficient to reduce MRSA transmission and infection

REALM update

Outline

1. MRSA surveillancea. Overview and main results

b. Contact precautions analysis

c. NICU analysis

2. KPC surveillance and future directions

REALM update

Outline

1. MRSA surveillancea. Overview and interim results

b. Contact precautions analysis

c. NICU analysis

2. KPC surveillance and future directions

REALM update

Neonatal ICU:MRSA epidemiology

• How does neonatal ICU MRSA colonization differ from that of adult ICU patients?

• Data from surveys 1-4• Presented at IDSA 2010

Neonatal MRSA+ distribution

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15-21

22-28

29-35

≥360

5

10

15

20

25

30

35

40

45

50

0

50

100

150

200

250

300

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450

500

Contact Precautions No Contact Precautions Total N

ICU day

Patients with MRSA (n) Total N

Adult MRSA+ distribution

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15-21

22-28

29-35

≥36

0

5

10

15

20

25

30

35

40

45

50

0

50

100

150

200

250

300

350

400

450

500

Contact Precautions No Contact Precautions Total N

ICU day

Patients with MRSA (n)

Total N

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15-21

22-28

29-35

≥3605

101520253035404550

050100150200250300350400450500

Contact Precautions No Contact Precautions Total N

ICU day

Patients with MRSA (n) Total N

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15-21

22-28

29-35

≥3605

101520253035404550

050100150200250300350400450500

ICU day

Patients with MRSA (n)

Total N

Neonatal ICU

Adult ICU

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15-21

22-28

29-35

≥3605

101520253035404550

050100150200250300350400450500

Contact Precautions No Contact Precautions Total N

ICU day

Patients with MRSA (n) Total N

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15-21

22-28

29-35

≥3605

101520253035404550

050100150200250300350400450500

ICU day

Patients with MRSA (n)

Total N

Neonatal ICU

Adult ICU

Median MRSA+

Median MRSA+

NICU Summary• MRSA colonization is common among neonatal

ICU patients

• For neonates, MRSA is uncommon early in ICU stay; rather, colonization appears days or weeks after admission

• If active surveillance is performed among neonates, it should be performed serially rather than only upon admission

REALM update

Outline

1. MRSA surveillancea. Overview and main results

b. Contact precautions analysis

c. NICU analysis

2. KPC surveillance and future directions

REALM update

KPC – emerging threat

• Klebsiella pneumoniae carbapenemase – usually found in Klebsiella spp., but can also be transmitted to other bacteria (E. coli, Pseudomonas).

• Carbapenems (imipenem) often last resort for treatment

• KPCs: no reliable antibiotic therapy, making some infections impossible treat.

REALM update

KPC PPS - Rationale

• First KPC isolated in Chicago ~ 2008• Increasing prevalence of KPC colonization

and infection– Nursing home / LTACH epicenters– Survey of Chicago hospitals – 65% in 2010

have isolated KPC• Goal:

– Determine prevalence of KPC colonization among ICU patients in Chicago

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Design

• Surveys 5 and 6 (July 2010 – June 2011)• Voluntary hospital participation• Adult ICUs (optional for NICU/PICU)• Initial design:

– Groin swab + urine culture (if urine bag present)

• Modified design: rectal culture• Lab – phenotypic screen for carbapenemase

resistance; confirmation using in-house PCR for blaKPC

REALM update

Results

Survey 5: 25 eligible hospitals ─ 1 remaining = 24 hospitals

6 hospitals: groin/urine culture only

2 hospitals: groin culture only

18 hospitals: rectal cultures

Patients: 459 adults (and 67 NICU/PICU)

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KPC results

• Overall KPC prevalence in adult ICUs:

17 / 459= 4%

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KPC future directions• Identify the extent of problem

– LTACH surveillance– Nursing home surveillance?– REALM survey 6 – KPC survey #2– Extending REALM for KPCs?

• Identify best practices to control KPCs– Chlorhexidine bathing? Environmental cleaning?

• Improve communication between facilities

REALM update

Thank you!• Co-investigators

– Rosie D. Lyles, Karen Lolans, Mary K. Hayden, Alexander J. Kallen, Stephen G. Weber, Robert A. Weinstein, and William E. Trick

• CDC– John Jernigan, Scott Fridkin

• Illinois Department of Public Health– Craig Conover

• Cook County department of public health– Sue Gerber

• Hospital epidemiologists and infection preventionists at all 26 hospitals