Human parvovirus B19 infections: routine diagnosis by a new nested polymerase chain reaction assay.

A nested primer PCR assay was developed to detect human parvovirus B19 in various clinical specimens in a routine diagnostic laboratory. Under optimized conditions the highly specific assay had a sensitivity of less than 10 genome units. For practical reasons, however, this sensitivity was adjusted to 10-100 virus genomes in diagnostic applications. Using clinical specimens from 200 patients with suspected B19 infection, nested PCR was shown to have important diagnostic advantages over the detection of B19 specific antibodies. The data suggest that on the basis of serological data as obtained with currently available test systems a considerable proportion of B19 infections would be misdiagnosed. Examples for the usefulness of the PCR assay in routine diagnosis are given.