Microwave treatment of breast milk for prevention of cytomegalovirus infection.

BACKGROUND: Breast milk (BM) is the best nutrition for very preterm infants (VPI), except when provided by human cytomegalovirus (HCMV)-seropositive mothers. Given that VPI are at high risk of developing a sepsis-like syndrome or cholestasis, methods for prevention of HCMV infection via BM have been investigated. Although Holder pasteurization (HP) is the gold standard, HP needs special instruments. Microwave (MW) is available anywhere, therefore, we performed this study to determine whether MW can be used for HCMV prevention. METHODS: Human cytomegalovirus Towne strain was added to formula, followed by heating procedure using HP or MW (at 500 W for 20, 30, 40, or 60 s). HFL-III cells were seeded in culture dishes. Aliquots of HCMV-milk samples after heating were inoculated onto susceptible cell monolayers. The number of plaques was counted to determine the viral titer. The determination of HCMV-DNA copies was also performed. RESULTS: Addition of HCMV for a viral load of 5.0 × 103 plaque-forming units (p.f.u.)/mL achieved 772 p.f.u./mL at baseline, with a decrease to 257 p.f.u./mL after MW radiation for 20 s. No plaque was detected after HP or MW for 30, 40, and 60 s. The temperature of the breast milk reached 60°C after MW radiation for 40 s. The number of HCMV-DNA copies did not change with MW. CONCLUSIONS: Microwave at 500 W for 40 s can be used as a prevention strategy for HCMV transmission. Further research including the loss of bioactive properties in BM is required prior to clinical application.

Increased detection of clinically significant antibodies and decreased incidence of delayed haemolytic transfusion reaction with the indirect antiglobulin test potentiated by polyethylene glycol compared to albumin: a Japanese study.

BACKGROUND: The indirect antiglobulin test (IAT) can be potentiated by agents such as polyethylene glycol (PEG-IAT) and albumin (Alb-IAT). PEG-IAT is generally regarded as superior to Alb-IAT for the detection of clinically significant red blood cell (RBC) antibodies. However, supporting data come from Caucasian-dominant populations. Non-Caucasian populations should be investigated as well. MATERIAL AND METHODS: In this single-centre, retrospective, sequential study, Alb-IAT was used from 1989 to 1996 (8 years) and PEG-IAT from 1997 to 2008 (12 years). Pre-transfusion RBC alloantibody detection rates and specificity, post-transfusion alloantibody production, and the incidence of delayed haemolytic transfusion reaction were assessed and compared for the two periods. RESULTS: Although overall RBC alloantibody detection rates were comparable, PEG-IAT more frequently detected clinically significant antibodies such as anti-E, anti-Fy(b), and anti-Jk(a), and less frequently detected insignificant antibodies such as anti-Le(b) and anti-P(1). New alloantibodies emerged comparably during the two periods. Delayed haemolytic transfusion reaction was less frequent during the PEG-IAT period (0.30% versus 0.12%, p<0.05). CONCLUSION: PEG-IAT was superior in the detection of clinically significant antibodies, reduced the detection of insignificant antibodies, and prevented delayed haemolytic transfusion reaction better than Alb-IAT among Japanese transfusion recipients in this retrospective survey of limited power.