CC BY-NC-ND 4.0 · J Lab Physicians 2009; 1(02): 069-072
DOI: 10.4103/0974-2727.59703
Original Article

Optimum Time to Detection of Bacteria and Yeast Species with BACTEC 9120 Culture System from Blood and Sterile Body Fluids

Nita Pal
Department of Microbiology, SMS Medical College, Jaipur, India
Rajni Sharma
Department of Microbiology, SMS Medical College, Jaipur, India
Suman Rishi
Department of Microbiology, SMS Medical College, Jaipur, India
Leela Vyas
Department of Microbiology, SMS Medical College, Jaipur, India
› Author Affiliations
Source of Support: Nil


The culture results of 4,807 blood and 383 sterile body fluid specimens received in our laboratory during a 54-month period, were analyzed to determine the time required for culture to become positive, time at which a culture could safely be considered negative, and the spectrum of isolated organisms. The specimens were processed by automated BACTEC 9120 culture system. A total of 1,677 clinically significant microorganisms were isolated. Gram positive and negative bacterial isolation rates were found to be 62.55% and 32.20%, respectively. Yeasts were recovered in 5.24%. False positivity rate was 1.5%. Clinically significant isolates recovered on day four and five were 97.81% and 99.88%, respectively. At day five, the sensitivity was 99.94% and negative predictive value 99.96%. Our data support a five-day incubation protocol for recovery of all clinically significant organisms with sensitivity reduced by 0.06%, when compared with a six-day protocol.

Publication History

Publication Date:
29 January 2020 (online)

© 2009.

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  • 1 Bloodstream infections. In: Forbes BA, Sahm DF, Weissfeld AS, editors. Bailey and Scott′s Diagnostic Microbiology. 11 th ed. Missouri: Mosby, Inc.; 2002. p. 865-83.
  • 2 Durmaz G, Tercan US, Aydinli A, Kiremitci A, Kiraz N, Akgun Y. Optimum detection times for bacteria and yeast species with the BACTEC 9120 aerobic blood culture system: Evaluation for a 5-year period in a Turkish University Hospital. J Clin Microbiol 2003;41:819-21.
  • 3 Reisner BS, Woods GL. Times to detection of bacteria and yeast in 9240 Blood culture bottles. J Clin Microbiol 1999;37:2024-6.
  • 4 Doern GV, Brueggemann AB, Dunne WM, Jenkins SG, Halstead DC, McLaughlin JC. Four-day incubation period for blood culture bottles processed with the Difco ESP blood culture system. J Clin Microbiol 1997;35:1290-2.
  • 5 Hardy DJ, Hulbert BB, Migneault PC. Time to detection of positive BacT/Alert cultures and lack of need for routine subculture of 5- to 7- day negative cultures. J Clin Microbiol 1992;30:2743-5.
  • 6 Baka S, Logginidis I, Efstratiou V, Panagiotopoulou E, Kaparos G, Gerolymatos K, et al. Time to positivity of BACTEC blood culture bottles, abstr. No. 1733_441. In Abstracts of the 17 th European Congress of Clinical Microbiology and Infectious Diseases ICC, Munich, Germany, 2007.
  • 7 Kara A, Kanra G, Cengiz AB, Apis M, Gür D. Pediatric blood culture: Time to positivity. Turk J Pediatr 2004;46:251-5.
  • 8 Bourbeau PP, Pohlman JK. Three days of incubation may be sufficient for routine blood cultures with BacT/Alert FAN blood culture bottles. J Clin Microbiol 2001;39:2079-82.
  • 9 Bourbeau PP, Foltzer M. Routine incubation of BacT/Alert FA and FN blood culture bottles for more than 3 days may not be necessary. J Clin Microbiol 2005;43:2506-9.
  • 10 McGowan KL, Foster JA, Coffin SE. Outpatient pediatric blood cultures: Time to positivity. Pediatrics 2000;106:251-5.
  • 11 Endimiani A, Tamborini A, Luzzaro F, Lombardi G, Toniolo A. Epidemiology of bloodstream infections and time to detection of positive blood culture: An evaluation of the automated BacT/Alert and BACTEC 9240 systems. New Microbiol 2002;25:9-16.
  • 12 Johnson AS, Touchie C, Haldane DJ, Forward KR. Four-day incubation for detection of bacteremia using BACTEC 9240. Diagn Microbiol Infect Dis 2000;38:195-9.
  • 13 Pauli I Jr, Shekhawat P, Kehl S, Sasidharan P. Early detection of bacteremia in the neonatal intensive care unit using the new BACTEC system. J Perinatol 1999;19:127-31.
  • 14 Gray J, Brockwell M, Das I. Experience of changing between signal and BACTEC 9240 blood culture systems in a children′s hospital. J Clin Pathol 1998;51:302-5.
  • 15 Kurlat I, Stoll BJ, McGowan JE. Time to positivity for detection of bateremia in neonates. J Clin Microbiol 1989;27:1068-71.
  • 16 Cockerill FR 3rd, Reed GS, Hughes JG, Torgerson CA, Vetter EA, Harmsen WS, et al. Clinical comparison of BACTEC 9240 Plus Aerobic/F resin bottles and the Isolator Aerobic culture system for detection of blood stream infections. J Clin Microbiol 1997;35:1469-72.
  • 17 Smith JA, Bryce EA, Ngui-Yen JH, Roberts FJ. Comparison of BACTEC 9240 and BacT/Alert blood culture system in an adult hospital. J Clin Microbiol 1995;33:1905-8.
  • 18 Nolte FS, Williams JM, Jerris RC, Morello JA, Leitch CD, Matushek S, et al. Multicenter clinical evaluation of a continuous monitoring blood culture system using fluorescent-sensor technology (BACTEC 9240). J Clin Microbiol 1993;31:552-7.
  • 19 Weinbaum FI, Lavie S, Danek M, Sixsmith D, Heinrich GF, Mills SS. Doing it right the first time: Quality improvement and the contaminated blood culture. J Clin Microbiol 1997;35:563-5.