Culture confirmation of cytomegalovirus and herpes simplex virus by direct enzyme-labeled DNA probes and in situ hybridization.

Using probes consisting of horseradish peroxidase (HRP) directly attached to DNA, scrapings or trypsinized cells from 217 adequate clinical samples were cultured and analyzed in 3 blind studies by in situ hybridization for the presence of cytomegalovirus (CMV) and herpes simplex virus (HSV). Sixty samples were judged inadequate due to insufficient cell numbers; however, this problem was significantly decreased during the course of the study. One hundred and eighteen samples were found positive and 70 samples were found negative for CMV. Scrapings of cultured cells from 29 clinical samples revealed 9 samples which were positive and 20 samples which were negative for HSV. Forty-two additional samples, containing either uninfected cells or cells infected with various strains of CMV, were analyzed for the ability of the HRP-DNA CMV probe to detect such isolates. Twenty samples were positive and 22 negative for CMV. No false-negatives or false-positives were observed for either CMV or HSV. In addition to the specificity noted above neither the CMV nor the HSV DNA probe hybridized to potential contaminants found in clinical specimens.