ABSTRACT
BACKGROUND AND OBJECTIVES: There is a growing infectious syphilis outbreak in Western Canada. Although blood donors are screened for syphilis risks, some blood donors will still be confirmed test-positive for syphilis. This study compares the characteristics of confirmed test-positive syphilis donations in both Western Canada and Eastern Canada, November 2022-August 2023. MATERIALS AND METHODS: Donors were defined as Western or Eastern Canadian. Blood donations were tested for syphilis using the PK-TP assay (Beckman Coulter PK7300 Automated Microplate System). Confirmatory Treponema pallidum particle agglutination (TPPA) and rapid plasma reagin (RPR) assays were performed by one of two reference laboratories. An RPR titre ≥1:8 was used as a proxy for possible infectious syphilis. RESULTS: Rates of laboratory-confirmed syphilis were higher in Western (n = 43, 13.4/100,000 donations) versus Eastern donors (n = 19, 4.7/100,000 donations; Fisher's exact test, two-sided, p ≤ 0.0001). Most syphilis confirmations were in first-time donors (Western Canada n = 31/43, 72.1%, Eastern Canada 12/19, 63.2%). CONCLUSION: Although rates of laboratory-confirmed syphilis were higher in Western versus Eastern donors, Western donors did not have higher rates of infectious syphilis. Further studies might assess whether donors with laboratory-confirmed syphilis understood pre-donation screening questions or were completely unaware of a past infection.
ABSTRACT
BACKGROUND: A systematic review and meta-analysis was performed to determine if there were differences between apheresis platelet concentrates (APCs) or platelets (PLTs) derived from whole blood (WBD) for the outcomes acute reactions, alloimmunization, refractoriness, corrected count increment (CCI), radiolabeled recovery and survival, time to next transfusion, and bleeding. STUDY DESIGN AND METHODS: We searched Medline, Embase, the Cochrane Registry of Controlled Trials, PapersFirst, ProceedingsFirst, and AABB and ASH abstracts for randomized controlled trials (RCTs) comparing APCs and WBD PLTs for clinical outcomes. Study selection, data extraction, and methodologic quality assessments were performed in duplicate. Results were pooled using meta-analytic methods. RESULTS: Ten RCTs met the inclusion criteria. Acute reactions per patient were lower for APCs (relative risk [RR], 0.65; 95% CI, 0.44-0.98); however, when controlling for leukoreduction, there was no significant difference (leukoreduced [LR]-APCs vs. LR-WBDs; odds ratio, 1.78; 95% CI, 0.87-3.62). There was no difference between products when reaction frequencies were assessed per transfusion (RR, 0.65; 95% CI, 0.33-1.28). APCs were associated with significantly higher CCIs than WBD PLTs at both 1 hour (weighted mean difference [WMD], 2.49; 95% CI, 2.21-2.77) and 18 to 24 hours (WMD, 1.64; 95% CI, 0.60-2.67). No conclusions could be made for the outcomes of alloimmunization and refractoriness. No studies addressed outcomes of time to next transfusion or bleeding. CONCLUSIONS: Owing to the small number of trials and lack of comparability of PLT products for leukoreduction, we were unable to draw definitive conclusions about the clinical benefits of APCs compared with WBD PLTs. Rigorous RCTs using clinically important end points are needed to settle this issue.
