1H NMR Urinary Metabolomics Profiling of Newborns with Congenital Human Cytomegalovirus Infection: Insights into Metabolic Alterations

: Human cytomegalovirus (HCMV) is the leading cause of congenital infections resulting in severe morbidity and mortality among newborns worldwide. Currently, the most significant prognostic factor of congenital cytomegalovirus (cCMV) infection is the time of maternal infection, with a more severe clinical phenotype if the mother's first outbreak occurs during the first trimester of pregnancy. Nonetheless, the pathogenesis of cCMV infection has still to be completely characterized. In particular, little is known about the metabolic response triggered by HCMV in congenitally infected newborns. As such, urinary metabolic profiling by 1H nuclear magnetic resonance (NMR) might represent a promising tool to be exploited in the context of cCMV. This study aims to investigate the impact of HCMV infection on the urine metabolome in a population of congenitally infected newborns and uninfected controls by 1H NMR spectroscopy combined with multivariate statistical analysis. The 1H NMR spectra of patients (n = 35) and controls (n = 15) allowed the identification of an overall amount of 55 metabolites. Principal Component Analysis (PCA) and clustering correctly assigned 49 out of 50 newborns into the infected and control groups. Partial Least-Squares-Discriminant Analysis (PLS-DA) revealed that newborns with cCMV resulted in having increased betaine, citrate, 3-hydroxybutyrate, 4-hydroxybutyrate, acetoacetate, formate, glycolate, lactate, succinate, and threonine levels in the urine. On the other hand, healthy controls showed increased 4-aminohippurate, creatine, creatinine, fumarate, mannitol, taurine, and dimethylamine levels. These results showed a clear difference in metabolomic fingerprint between newborns with cCMV infection and healthy controls. Thus, metabolomics can be considered a new, promising diagnostic and prognostic tool in the clinical management of cCMV patients.