Effect of double dose plateletpheresis on target yield and donor platelet recovery

Abstract Introduction The demand for apheresis platelets has increased in the recent past and the shrinking donor pool has shifted the trend to collection of double-dose or higher yield of platelets. Objective The present study aimed to determine the effect of double-dose plateletpheresis on the target yield and donor platelet recovery. Methods The study was conducted on 100 healthy plateletpheresis donors, 50 of whom were in the study group, which underwent double-dose plateletpheresis (DDP), and 50 of whom were in the control group for single-donor plateletpheresis. Pre- and post-procedure samples of donors were subjected to a complete blood count. The DDP product was sampled for platelet yield and then split into two parts. Platelet yield, collection efficiency, collection rate, recruitment factor and donor platelet loss were calculated. Results The mean platelet yield in the SDP was 4.09 ± 1.15 × 1011 and in the DDP, 5.93 ± 1.04 × 1011. There was a significant correlation between the pre-donation platelet count and platelet yield. The total of platelets processed for the SDP were 5.42 ± 1.08 × 1011 and for the DDP, 7.94 ± 0.77 × 1011. The collection efficiency was 71.93 ± 25.14% in the SDP and 72.94 ± 16.28% in the DDP, while the collection rates were 0.78 × 1011 and 0.94 × 1011 per minute, respectively. The average recruitment factor observed was 0.98 in the SDP, while it was 0.99 in the DDP. The mean platelet loss observed in the SDP was 35.55 ± 8.53% and in the DDP, 37.76 ± 8.65%. Conclusion The double-dose plateletpheresis supplements the platelet inventory in developing countries where the apheresis donor pool is limited. It is prudent to ensure stringent donor selection criteria for donors donating high-yield platelet products, thus enhancing donor safety and retention.

Low-Tube-Voltage CT Urography Using Low-Concentration-Iodine Contrast Media and Iterative Reconstruction: A Multi-Institutional Randomized Controlled Trial for Comparison with Conventional CT Urography

OBJECTIVE: To compare the image quality of low-tube-voltage and low-iodine-concentration-contrast-medium (LVLC) computed tomography urography (CTU) with iterative reconstruction (IR) with that of conventional CTU. MATERIALS AND METHODS: This prospective, multi-institutional, randomized controlled trial was performed at 16 hospitals using CT scanners from various vendors. Patients were randomly assigned to the following groups: 1) the LVLC-CTU (80 kVp and 240 mgI/mL) with IR group and 2) the conventional CTU (120 kVp and 350 mgI/mL) with filtered-back projection group. The overall diagnostic acceptability, sharpness, and noise were assessed. Additionally, the mean attenuation, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and figure of merit (FOM) in the urinary tract were evaluated. RESULTS: The study included 299 patients (LVLC-CTU group: 150 patients; conventional CTU group: 149 patients). The LVLC-CTU group had a significantly lower effective radiation dose (5.73 ± 4.04 vs. 8.43 ± 4.38 mSv) compared to the conventional CTU group. LVLC-CTU showed at least standard diagnostic acceptability (score ≥ 3), but it was non-inferior when compared to conventional CTU. The mean attenuation value, mean SNR, CNR, and FOM in all pre-defined segments of the urinary tract were significantly higher in the LVLC-CTU group than in the conventional CTU group. CONCLUSION: The diagnostic acceptability and quantitative image quality of LVLC-CTU with IR are not inferior to those of conventional CTU. Additionally, LVLC-CTU with IR is beneficial because both radiation exposure and total iodine load are reduced.

Persistence of Protective Hepatitis B Surface Antibody Titers after Successful Double-Dose Hepatitis B Virus Rescue Vaccination in HIV-Infected Patients

BACKGROUND/AIMS: To assess the durability of protective hepatitis B surface antibody (anti-HBs) titers in HIV-infected patients who responded to double-dose hepatitis B virus (HBV) rescue vaccination. METHODS: A retrospective chart review was performed for HIV-infected patients who received the double-dose HBV rescue vaccination at 0-, 1-, and 2-month intervals after they had failed conventional HBV vaccination series. A protective antibody response was defined as an anti-HBs titer > or =10 mIU/mL. RESULTS: Of 54 HIV-infected patients who received a double-dose HBV rescue vaccination, 44 patients (81.5%) had a positive response and achieved protective anti-HB titers. Of the 44 patients who developed protective anti-HB titers, 33 patients received an evaluation of their anti-HB titers 12 months later. Of the 33 patients, 19 (57.6%) had persistent protective anti-HB titers (persistent responders, PR), and 14 patients (42.4%) lost their protective anti-HB titers (nonpersistent responders, NPR). There were significantly more patients who had an undetectable HIV viral load (<50 copies/mL) at baseline and follow-up in the PR group (11/19, 57.9%) than in the NPR group (3/14, 21.4%, p=0.036). Logistic regression analysis showed that an undetectable HIV viral load at baseline and follow-up (odds ratio, 12.973; 95% confidence interval, 1.189 to 141.515; p=0.036) was associated with PR. CONCLUSIONS: Protective anti-HB titers may decrease over time after successful double-dose HBV rescue vaccination in HIV-infected patients. HIV viral load suppression could improve the persistence of anti-HB titers.

The risk factors of the nonresponders after hepatitis B vaceinatio and the immunogenecity after a double-dose revaccination in the nonresponders

BACKGROUND: Korea is an endemic area of viral hepatitis B with a rate of 5~10% carrier state. Therefore, hepatitis B vaccination is performed nationwide. But 5~15% of healthy individuals fail to respond adequately to the vaccine and an approved guideline for the nonresponders has not been developed yet. This study is designed to identify risk factors for those who lack anti-HBs after hepatitis B vaccination and to document the results of a double-dose revaccination in such nonresponders to the primary vaccination. METHODS: From Feb. 1996 to Aug, 1997, we assessed 51 healthy subjects(HBs Ag negative, anti-HBs negative, anti-HBc negative and a normal LFT). All subjects were vaccinated with Hepavax- B, 1.0ml, 24 by a rapid schedule(0, 1, and 2 months) and 27 by a standard schedule(0, 1, and 6 months). Anti-HBs titers were evaluated 3 months after the third vaccine and assessed the nonre-sponders (anti-HBs titer<2mIu/ml) and the hyporesponders(2~10mK/ml). All 13 nonresponders were revaccinated with 2ml of Hepavax-B 3 months after the primary vaccination. Anti-HBs titers were evaluated 1 month later. RESULTS: The differences in age(p<0.01) and smoking amount(p<0.05) between the responders and the hypo and the nonresponders were statistically significant. There were more males and higher body mass index in the hypo and the nonresponders but not statistically significant. The seroconversion rate after the double-dose vaccination was 92.3%(12/13) with an average titer of 5K08mlU/ ml(1-132.4mIU/ml). CONCLUSIONS: Increase in age and smoking amount were the risk factors of the nonresponders after the primary vaccination. Most of the hypo and the nonresponders to the primary vaccination responded adequately to the double-dose revaccination.