ABSTRACT
【Objective】 To investigate the effectiveness of current indicators in initial screening and retest before donation and access the optimal testing strategies. 【Methods】 Data of initial screening (rate method for ALT, colloidal gold method for HBsAg) and retest (rate method for ALT, ELISA for HBsAg) of 18 510 platelet donors in our center from January 2019 to December 2021 were collected, and the results were retrospectively analyzed and compared in terms of different years and number of donations. 【Results】 From 2019 to 2021, data of initial screening and retest of platelet donors were as follows: 1) the deferral rate of ALT and HBsAg was 12.98% (2 403/18 510) vs 0.26%(40/15 412); 2) the deferral rate of ALT was 13.19% (712/5 398) vs 0.20%(9/4 410)in 2019, 13.33% (873/6 549) vs 0.06%(3/5 387)in 2020 and 11.05% (725/6 563) vs 0.07%(4/5 615)in 2021; for initial screening, significant difference was noticed in ALT reactivity in 2021 as in comparison to other two years(P<0.05); 3) the reactive rate of HBsAg was 0.43% (23/5 398) vs 0.18%(8/4 410)in 2019, 0.66% (43/6 549) vs 0.20%(11/5 387)in 2020 and 0.41% (27/6 563) vs 0.09%(5/5, 615) in 2021. For initial screening, HBsAg deferral in 2021 was significantly different from 2019, while similar with 2020. 4) Among ALT deferral samples in the retest, 68.75% (11/16) were ALT≥45 U/L. Among HBsAg reactive samples, 91.67% (22/24) were reactive by single reagent. 【Conclusion】 Setting the threshold value of ALT for platelet donors in initial screening as less than 45 U/L can effectively reduce the reactive rate in the retest. HBsAg screening only for first-time platelet donors can reduce the detection cost. Adding pre-donation detection indicators according to local prevalence of transfusion transmitted diseases is conductive to reduce the discarding rate of platelets.
ABSTRACT
【Objective】 To explore the deferral causes of apheresis platelet donors during primary screening in Qinghai, so as to take appropriate measures to improve the pass rate of donors. 【Methods】 The primary screening results of 6 673 apheresis donors from January 2018 to January 2020 in Qinghai were analyzed retrospectively. And the deferral results of donors were compared according to high(>2 500 m), middle(about 2 000 m) and low(<1500 m) altitude. 【Results】 41.7%(531) of those high-altitude blood donors were deferred, as low Plt accounted for 13.2%(168), high ALT 11.9%(151), high Hct/Hb/RBC 11.8%(150), and limepic blood 4.0%(51). 8.1% of the middle-altitude donors were deferred. As for low-altitude donors, low HCT, Hb and RBC(0.6%, 8 cases) were the dominant reason. 【Conclusion】 The different altitudes and living habits of blood donors may result in their deferral. Appropriate measures should be carried out for apheresis donors from areas of different altitudes when recruiting donors, so as to elevate the pass rate.
ABSTRACT
BACKGROUND: As apheresis platelet concentrates are widely used recently, the risk of transfusion associated infections is increased. Parvovirus B19 causes transfusion associated infections especially in chronic hemolytic anemia, haemophilia or immunosuppressed patients. We evaluated the significance of Parvovirus B19 antigen test to be one of the apheresis platelet donor screening test. METHODS: Three hundred forty eight serum (or plasma) samples from apheresis platelet donors were tested for Parvovirus B19 antigen test which was based on haemagglutination in gel technology. The tubes arranged in special gel cards (DiaMed) were added with 25 microL P antigen positive red cell and 10 microL patient's serum and then centrifuged at room temperature, 85 g for 10 minutes without incubation. The result was read and scored from 0 to 4 positive. Also the antibody screening test was performed for all of the positive samples on the Parvovirus B19 gel card test to exclude false positive reaction due to red cell alloantibody. We investigated directed recipient's disease state for all of positive donors and compared the result of the Parvovirus B19 antigen test with the routine screening test. RESLUTS: Six of the 348 samples were positive for Parvovirus B19 antigen test, the frequency was 1.7%. All of the six positive samples on gel card test reveal negative result by the antibody screening test. All of four directed recipients are immunosuppressed states. If the Parvovirus B19 antigen test was included in routine screening test, the rejection rate is expected to be increased about 1.4%. CONCLUSION: Screening for Parvovirus B 19 in apheresis platelet donors is considered to prevent transfusion mediated viral infection of susceptible recipients including immunocompromised patients.