Presentation on theme: "Update on the AABB Standards and platelet bacterial contamination TAC: MVRBC 2011."— Presentation transcript:
Update on the AABB Standards and platelet bacterial contamination TAC: MVRBC 2011
Standard 184.108.40.206 The blood bank or transfusion service shall have methods to limit and to detect or inactivate bacteria in all platelet components. Standard 5.6.2 applies. –Venipuncture skin prep and diversion
Association Bulletin 09-04 “…after publication of data sufficiently robust…the current standard will be reappraised. At that time, AABB intends to promulgate an interim standard to require enhanced methods of bacterial detection in WBD platelets—either by specifically prohibiting the use of less sensitive methods such as pH or glucose, or by establishing a minimum sensitivity level for methods used to detect bacteria. At this time, transfusion services using uncultured WBD platelets should begin to consider their options.”
Interim Standard 220.127.116.11.1 Detection methods shall either be approved by the FDA or validated to provide sensitivity equivalent to FDA-approved methods. Effective date of January 31, 2011.
Bacterial deaths reported to FDA http://www.fda.gov/BiologicsBloodVaccines/SafetyAvailability/ReportaProblem/ TransfusionDonationFatalities/ucm204763.htm
Contamination rate/10 6 based on early (release) culture: optimal arm prep and diversion pouch Corash, L. Expert Rev. Heme. 2011
Rates/10 6 of bacterial contamination detected with culture-based testing at expiration Corash, L. Expert Rev. Heme. 2011
Confirmed cultures (per sample tested) WBD vs. apheresis platelets WBDApheresis Study Pool sizeMethodN Rate/ 10 6 N Rate/ 10 6 OR (95%CI) Benjamin, US 5PRP20,725965431,490167 5.8 (3.5-9.5) Yomtovian, US 5PRP12,9612,39215,493452 5.3 (2.3-12.0) Schrezenmeier, Germany 5BC22,04472615,198855NS Murphy, Ireland 5BC30,40732912,823312NS de Korte, Netherlands 5BC6,7491,3224,9632,418NS Adapted from Benjamin et al. Transfusion. 2008
Clinical vs. analytical sensitivity Yomtovian et al. CID. 2008.
LOD for bacteria in platelets with Verax PGD ® Verax PGD PI. 2010.
Performance of Verax PGD ® at ITxM WBD platelet pools Test WBD platelets screened Positive tests Positive culturesSpec.PPVp PGD773314299.8514.3.014 pH37060405498.931.0 After Yazer et al. AJCP. 2010
Verax PGD and apheresis platelets (negative release culture at time of issue) Jacobs et al. Transfusion. 2011 Repeat reactive PGD 152 Culture negative 142 False pos PGD Culture positive 9 True pos PGD Culture negative 10,342 True neg PGD Culture positive 2 False neg PGD Recultured 10,344 Negative PGD 27,469 AP doses w/ valid PGD 27,620.55%.514%.033%.019%99.980%
Options to meet the intent of 18.104.22.168.1 PGD ® within 4 h. of transfusion on WBD pools: point of issue; Prepooled WBD platelets tested by supplier with approved culture-based QC test; Culture aliquots from WBD units at pooling; Use methods not FDA-cleared but validated to be of equivalent sensitivity to an approved assay, subject to review at the time of accreditation assessments. Use apheresis platelets tested by supplier with approved culture-based QC test; Should PGD (or equivalent) be used in transfusion service?
What else? pH, glucose and microscopy will NOT be acceptable Use of untested WBD pools (e.g. ≤3 days) will require validation Use of Verax at ≤72 hr. may detect clinically important bacteria, and should be considered when other sensitive alternatives are not available Optimal practice is to test WBD pools before LR (per PI); testing after LR may be considered if workflow or clinical constraints demand Urgent platelet release without or during QC testing is “practice of medicine” and is acceptable if addressed in facility SOPs.