Contents

Search

blood culture

Indications: - bacteremia - septicemia Specimen: 1) adults a) collect 20 mL of blood b) divide equally between 2 100 mL culture bottles or between a 100 mL blood culture bottle & a lysis centrifugation tube c) divide 5 mL into aerobic & anaerobic bottles & 10 mL into another blood culture system 2) infants a) collect 1-5 mL of blood per 100 mL culture bottle b) collect both aerobic & anaerobic cultures 3) sodium polyanetholesulfonate (SPS, 0.025-0.05%) should be included in culture bottles 4) use of sterile gloves reduces contamination rate [4] 5) sterile technique & a checklist reduces contamination rate by nearly 50% [5] * specify if fastidious organisms are suspected (Brucella, leptospirosis) Clinical significance: - two sets of blood cultures collected at different sites should be obtained with each episode of fever - all blood cultures should be positive if bacterial endocarditis is the source of bacteremia - for other sources of bacteremia, there may be more intermittent shedding of organisms into the blood - prior antimicrobial therapy may reduce the yield - sodium polyanetholesulfonate (SPS, 0.025-0.05%) included in culture bottles as anticoagulant may interfere with recovery of Neisseria gonnorhoeae & Neisseria meningitidis - gram staining of blood cultures read as negative in an automated system revealed slow-growing pathogens in 0.13% of cultures [6] Management: - all positive blood cultures should be followed with echocardiography to assess presence of endocarditis [3] a) transthoracic echocardiogram (TTE) on all patients b) transesophageal echocardiogram (TEE) if TTE is negative

Related

blood blood culture isolator (lysis centrifugation)

Specific

bacteria identified in blood by culture bacteria identified in cord blood by culture blood culture for fungus/Mycobacterium

General

culture

References

  1. Clinical Guide to Laboratory Tests, 3rd ed. Teitz ed., W.B. Saunders, 1995
  2. Harrison's Principles of Internal Medicine, 13th ed. Isselbacher et al (eds), McGraw-Hill Inc. NY, 1994, pg 491
  3. Medical Knowledge Self Assessment Program (MKSAP) 14, American College of Physicians, Philadelphia 2006
  4. Kim N-H et al. Effect of routine sterile gloving on contamination rates in blood culture: A cluster randomized trial. Ann Intern Med 2011 Feb 1; 154:145 PMID: 21282693 - Kim JY and Rosenberg ES. The sum of the parts is greater than the whole: Reducing blood culture contamination. Ann Intern Med 2011 Feb 1; 154:202. PMID: 21282700
  5. Journal Watch. Jan 30, 2014 Massachusetts Medical Society http://www.jwatch.org - Self WH et al. Reducing blood culture contamination in the emergency department: An interrupted time series quality improvement study. Acad Emerg Med 2013 Jan; 20:89 PMID: 23570482 - Hall RT, Domenico HJ, Self WH, Hain PD. Reducing the blood culture contamination rate in a pediatric emergency department and subsequent cost savings. Pediatrics. 2013 Jan;131(1):e292-7 PMID: 23209105
  6. Peretz A et al. Performance of Gram staining on blood cultures flagged negative by an automated blood culture system. Eur J Clin Microbiol Infect Dis 2015 Apr 16; PMID: 25877009 http://link.springer.com/article/10.1007%2Fs10096-015-2383-0