Incidence of HCV and HIV NAT Positive in Cord Blood Donors.

Introduction:

Donors of cord blood (CBD) are screened similarly to whole blood donors (WBD). It has been reported that CBD have a higher incidence of both true positive and false positive disease markers tested by EIA[1]. This abstract compares the rate of positive results for viral RNA (NAT) in CBD vs. WBD in a large cohort of donors.

Methods:

NAT was performed using the Chiron Procleix MPX or discriminatory assays. EIA testing was performed using Abbott bead methodology following manufacturer’s instructions. Confirmatory results for EIA were performed with Chiron RIBA. Results from 12/17/04 to 6/30/05 were collated.

Results

A higher percentage of CBD were positive for HIV and HCV EIA as previously reported¹. HIV NAT positive donors were 0.00% for both populations. The ratio of HCV EIA positive to HCV NAT positive donors was 28.97% for WBD and 28.26% in CBD. The ratio of CBD HCV EIA positives to WBD HCV EIA positives is 2.71 and the ratio of WBD HCV NAT positives to WBD HCV NAT positives is 2.75. The ratio of HIV CBD EIA positives to HIV WBD EIA positives is 4.10, which is significantly higher (p=<0.01).

Conclusions

Both CBD and WBD have a low rate (0%) of HIV NAT positive donors, but CBD have a 4x higher rate of HIV EIA. This suggests a 4x higher donor loss to false positive antibody results. The CBD donors have a 2.7x higher rate for both EIA and NAT positive results, showing a higher rate of viremic donors in CBD. The similar ratios for EIA positive to NAT positive donors in the two populations suggest that the false positive rate is not elevated in CBD versus WBD.

The higher incidence of HCV infection in CBD could be geographic or ethnic in origin. More study is needed to determine the reasons and further predict donor loss. The HIV EIA results are not predictive of actual infection in this population. A more aggressive logarithm for reentry than used for WBD may be merited.