Clinical Value of Serial Quantitative Analysis of Cytomegalovirus DNA in Blood and Saliva Over the First 24 Months of Life in Congenital Infection: The French Cymepedia Cohort

Abstract

Objective: To evaluate cytomegalovirus (CMV) viral load dynamics in blood and saliva during the first 2 years of life in symptomatic and asymptomatic infected infants and to identify whether these kinetics could have practical clinical implications.

Study design: The Cymepedia cohort prospectively included 256 congenitally infected neonates followed for 2 years. Whole blood and saliva were collected at inclusion and months 4 and 12, and saliva at months 18 and 24. Real-time CMV polymerase chain reaction (PCR) was performed, results expressed as log₁₀ IU/mL in blood and in copies per milliliter in saliva.

Results: Viral load in saliva progressively decreased from 7.5 log₁₀ at birth to 3.3 log₁₀ at month 24. CMV PCR in saliva was positive in 100% and 96% of infants at 6 and 12 months, respectively. In the first month of life, neonatal saliva viral load of less than 5 log₁₀ was related to a late CMV transplacental passage. Detection in blood was positive in 92% of neonates (147/159) in the first month of life. No viral load threshold values in blood or saliva could be associated with a high risk of sequelae. Neonatal blood viral load of less than 3 log₁₀ IU/mL had a 100% negative predictive value for long-term sequelae.

Conclusions: Viral loads in blood and saliva by CMV PCR testing in congenital infection fall over the first 24 months. In this study of infants affected mainly after primary maternal infection during pregnancy, all salivary samples were positive in the first 6 months of life and sequelae were not seen in infants with neonatal blood viral load of less than 3 log₁₀ IU/mL.