Improving Blood Culture Sensitivity WHEN AND WHY Blood ...

Patients on Antibiotics
• Four blood culture studies reported the
number of patients on antibiotics when
blood cultures were obtained
– 36% (J Clin Micro 35:2634-2638, 2638 1997)
– 32.9% (J Clin Micro 35:53-58, 1997)
– 28.6% (Clin Infec Dis 24:584-602, 1997)
– 63% (J Clin Micro 33:2856-2858, 1995)
Break-Through Bacteremia (BTB)
Occurs when patient is receiving antibiotics to which
offending organism is susceptible, but still has bacteria in
the bloodstream.
Critical to patient management and survival and
reimbursements to know if patient has BTB.
Concentration of antibiotic(s) may be too low.
Inadequate drainage or major problems at
focus of infection that must be addressed.
BACTEC RESIN vs
BACT/ALERT STANDARD
Smith et al. JCM 33:1905-1908 (1995)
• 10,000 bottle study
• Bact/Alert std missed 33% of Staph
aureus. Staph aureus detected t d by
Bactec resin
• Bact/Alert standard missed 25% of
cases of Pseudomonas
• Large sepsis reimbursement losses
Clinical Comparion of BACTEC Resin
Media and BacT/Alert FAN Media
• Comparative Yield of
Clinically Important
Bacteria and Yeast from
Patients Receiving
Antibiotic Therapy
– BACTEC recovered approx.
8% more isolates from
patients receiving
antimicrobial therapy.
– More of the isolates were
those that were among the
top 10 isolates that typically
occur in blood cultures.
Greater recovery of
gram neg bacilli
BacT/Alert had higher
recovery of:
S. Aureus S. pneumoniae
E. faecalis C. albicans
E. faecium C. neoformans
E. Coli C. glabrata
E. cloacae
Other enterics
P. aeruginosa
Other Gram-bacili
H. capsulatum
Jorgenson, et al. JCM, Vol 35, No. 1, p. 53-58, Jan 1997
FAN BOTTLE vs.
BACT/ALERT STANDARD
McDonald et al. JCM 34:2180-87 (1996)
• Analyzed 1,047 positive blood cultures
• Bact/Alert standard missed 126 cases of
septicemia
• Chart review showed that 65% of the
cases missed by standard bottle clinically
significant. Lost reimbursements.
Fan Bottle Helpful Hint
• Tilt slide slightly
• Put blood culture fluid at top of the tilt
• Put blood culture fluid at top of the tilt
• Charcoal particles should run down toward
bottom of tilt
• Bacteria should stay near the top
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