Effect of delayed processing of blood samples on performance of cytomegalovirus antigenemia assay

This prospective, parallel, and blind study of 120 blood samples from immunocompromised patients examined the influence of delayed sample processing on cytomegalovirus antigenemia assay. Cytomegalovirus was detected in 49 samples (40.8%): 41 were processed within 2 to 4 h, and 40 were reprocessed the following day. Results were discrepant in 17 of the samples with the lowest positive cell counts. Differences between the two days did not reach statistical significance.