182. Are Cultures of Central Line Intravascular Catheter Tips Valuable in the Management of Central Line-Associated Bloodstream Infection (CLABSI)?
Session: Poster Abstract Session: Catheter-associated BSIs
Thursday, October 3, 2013
Room: The Moscone Center: Poster Hall C
Background:

National Healthcare Safety Network (NHSN) criteria do not require a positive catheter tip culture for the diagnosis of CLABSI. In addition, the clinical benefit of collecting catheter tip cultures is unknown. 

Methods:

We retrospectively reviewed all cases of CLABSI identified between 1.1.2009 and 9.30.2012 at NUHS, an 832 bed, university- affiliated health system. A catheter tip culture (roll-plate method) was associated with an episode of CLABSI if it was received within 10 days of the initial positive blood culture. Episodes were categorized as  “concordant “ if the culture and susceptibility testing from both the blood and catheter tip were identical. Those that were not were categorized as “discordant” (negative or other organism).  The laboratory cost was estimated to be  USD $ 75.00 / culture

Results: 366 episodes of CLABSI were reviewed. 116 were associated with a catheter tip culture. 

ORGANISM associated with CLABSI

EPISODE OF CLABSI ASSOCIATED WITH A CATHETER TIP CULTURE (%)

NO CATHETER TIP CULTURE

No.  (%)

 

CONCORDANT

DISCORDANT 

 

 

NEGATIVE

OTHER

MSSA

14

4

2

22

42 (11.5)

MRSA

8

3

3

16

30 (8.2)

Coagulase-negative staphylococci

8

7

3

49

67 (18.3)

Gram-negative bacilli

14

22

7

85

128 (35)

Yeast

1

3

2

19

25 (6.8

enterococcus

3

5

0

34

42 (11.5)

Gram-positive cocci

1

5

0

24

30 (8.2)

Other

0

1

0

1

2 (0.5)

Total  

49 (42)

50 (43)

17 (15)

250

366

Catheter tips were submitted for culture an average of 2.31 days (+2.25, concordant) or 3.5 days  (+2.83, discordant) following the initial positive blood culture (unpaired 2 tail t test, p=0.02). 

Conclusion:

Catheter tip cultures are unlikely to be helpful in the clinical management of CLABSI due to the retrospective nature of the results, time delay to catheter tip results, and the high frequency of discordant results.  Discordant results may be explained by concomitant antimicrobial therapy, improper diagnosis of CLABSI, presence of a biofilm, or that a different catheter was the source. The value of catheter tip cultures in CLABSI appears questionable.  The estimated cost savings, not including unnecessary antimicrobials would be ~ $ 32,000 .00 (45 months).

Jeffery Semel, MD, Infectious Diseases, Northshore University HealthSystem, Evanston, IL; Internal Medicine, Pritzker School of Medicine, University of Chicago, Chicago, IL and Becky Smith, MD, Infection Control, NorthShore University HealthSystem, Evanston, IL; Infectious Diseases, Pritzker School of Medicine, University of Chicago, Chicago, IL

Disclosures:

J. Semel, None

B. Smith, None

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