Contribution of Serum Cytomegalovirus PCR to Diagnosis of Early CMV Primary Infection in Pregnant Women

(1) Background: What is the role of serum CMV PCR in the diagnosis of recent primary infection (PI) in pregnant women when IgG avidity is uninformative? (2) Methods: Retrospective cohort study to compare serum versus whole blood CMV PCR. (a) Qualitative assessment: CMV PCR was performed on 123 serum samples and 74 whole blood samples collected from 132 pregnant women with recent CMV PI. PCR positivity rate was used to calculate sensitivity in serum and whole blood. (b) Quantitative assessment: CMV PCR was performed on 72 paired samples of serum and whole blood collected on the same day from 57 patients. (3) Results: In pregnant women, PCR positivity rate was 89% for serum samples versus 100% in whole blood in the case of very recent PI (