title: Validation of a microbial detection system for use with ACD-A platelets with PAS III platelet additive solution.
abstract: BACKGROUND
  The BacT/ALERT microbial detection system (BTA) is used for testing leukoreduced apheresis platelets (LR-AP) in plasma. Platelet additive solutions (PASs) such as InterSol (PAS III) may be used to reduce the amount of plasma transfused in LR-AP. This study evaluated the performance of the two-bottle BTA testing scheme in the recovery of seeded microorganisms from LR-AP in InterSol-plasma compared to a reference plate culture method.
  
  
  METHODS
  Hyperconcentrated, double LR-AP were collected from healthy donors; InterSol was added (65% Intersol:35% plasma), equally divided into two containers, and then inoculated with an isolate of 1 of 10 clinically relevant index organisms at two levels. Aerobic (BPA) and anaerobic (BPN) BTA bottles were inoculated with 4 mL each of the inoculated LR-AP, and blood agar plates (BAPs) for aerobic and anaerobic culture (0.5 mL each).
  
  
  RESULTS
  Zero false-positives from 103 bottle pairs were observed. All 400 two-bottle BTA tests were positive within 24 hours, except for Propionibacterium acnes (maximum time-to-detection of 86.4 hr) and 13 of 20 pairs of Streptococcus viridans (maximum time-to-detection of 31.7 hr). Thirteen of 400 BAP two-plate tests were negative for starting bacterial concentrations of 10 colony-forming units (CFUs)/mL or less. At 40 CFUs/mL or less, BTA was 100% positive while BAP was 94% positive.
  
  
  CONCLUSIONS
  Seeded organism recovery was superior in the two-bottle BTA test system compared to the two-plate BAP system using InterSol platelets (PLTs). This performance is comparable to previously published results for PLTs in plasma. The use of InterSol does not appear to have a detrimental effect on the performance of the two-bottle BTA system.
authors.affiliation: Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire 03756, USA. larry.j.dumont@hitchcock.org
authors.forename: Larry J
authors.initials: LJ
authors.lastname: Dumont
authors.forename: Shauna N
authors.initials: SN
authors.lastname: Hay
authors.forename: Louise
authors.initials: L
authors.lastname: Herschel
authors.forename: Barbara
authors.initials: B
authors.lastname: Brantigan
authors.forename: Jaime
authors.initials: J
authors.lastname: Houghton
authors.forename: M Dean
authors.initials: MD
authors.lastname: Elfath
authors.forename: Mark E
authors.initials: ME
authors.lastname: Brecher
mesh_terms: D000925:Anticoagulants; D001420:Bacteria, Aerobic / Q000302:isolation & purification; D001421:Bacteria, Anaerobic / Q000302:isolation & purification; D001431:Bacteriological Techniques / Q000379:methods*; D001792:Blood Platelets / Q000382:microbiology*; D058731:Blood Safety / Q000379:methods*; D019343:Citric Acid; D015169:Colony Count, Microbial; D005188:False Negative Reactions; D005189:False Positive Reactions; D005947:Glucose / Q000031:analogs & derivatives; D006801:Humans; D047589:Leukocyte Reduction Procedures; D010949:Plasma / Q000382:microbiology*; D010983:Plateletpheresis / Q000379:methods*; D011310:Preservatives, Pharmaceutical
chemical_list: D000925:Anticoagulants; D011310:Preservatives, Pharmaceutical; C002113:acid citrate dextrose; D019343:Citric Acid; D005947:Glucose