No abstract

One-year ID-NAT screening of 732,250 donations interdicted 16 HIV, 20 HBV, and 1 HCV window phase donations and 42 anti-hepatitis B core antigen-reactive infections during an early recovery or a later stage of occult HBV infection.

We report the first known case of transfusion-transmitted HBV infection by blood screened using ID-NAT giving an observed HBV transmission rate of 0.34 per million. The estimated pre-acute-phase transmission risk in the ID-NAT screened donor population was 73-fold higher than the observed WP transmission rate.

Background and Objectives Changes in in vitro platelet quality parameters during platelet storage are associated with a decrease of in vivo platelet viability after platelet transfusion. Many attempts have been made to identify the most predictable in vitro parameters for in vivo performance. We used a riboflavin-based ultraviolet (UV) light treatment process designed to inactivate pathogens and white blood cell (WBC) contaminants in blood products as a model system in which to study the correlation of in vitro cell quality with in vivo viability. Materials and MethodsPlatelet products ( n = 18) were collected by a standard Trima apheresis procedure and treated with one of three dose levels of UV light (0, 7·2 or 12·4 J/ml) in the presence of 50 µ M riboflavin. Lactate production, glucose consumption and P-selectin expression, pH, pCO 2 , pO 2 , hypotonic shock response and swirl were measured during 5 days of platelet storage post-UV/RB treatment. Aliquots of these products were radiolabelled on day 5 of storage and were subsequently used to determine platelet recovery and survival time in autologous subjects. ResultsThe responses of in vitro cell quality were observed to occur in a UV dosedependent manner. Lactate production and pH were identified as the parameters most strongly correlated with platelet in vivo recovery, which ranged from 5 to 82%. The correlation coefficients ( r ) for lactate production and pH with in vivo recovery in human subjects were 0·9090 and 0·8831 with P -values of 0·007 and 0·031, respectively. Lactate production and pH were also found to be correlated with platelet survival time, with correlation coefficients of 0·8063 and 0·8384 (the P values were 0·01 and 0·001, respectively).Conclusions Using conditions of riboflavin-based UV light treatment, lactate production and pH were identified as having the highest correlations with recovery and survival of radiolabelled platelets in healthy subjects.Key words: in vitro platelet quality, in vivo platelet recovery, platelet survival, platelet viability prediction, UV light treatment.