Cordocentesis in fetuses with congenital cytomegalovirus

TO THE EDITORS: We thank Arossa et al for their comment.1 In our letter,2 we inquired with the authors3 about the use of cordocentesis in fetuses with normal prenatal im- aging at midgestation, because the risk of moderate to severe fetal sequelae seems to be low. Sensorineural hearing loss or other neurodevelopmental abnormalities cannot be com- pletely excluded in cases of normal imaging. Prenatally, ul- trasound abnormalities in congenital cytomegalovirus (CMV) infection have been classi ed as severe brain abnormalities, mild brain abnormalities, or extracerebral abnormalities, ac- cording to Leruez-Ville et al.4 Severe fetal brain lesions are associated with a poor prognosis, while the prognosis of fetuses with mild brain ultrasound abnormalities or extracerebral abnormalities remains uncertain. Thrombocytopenia, high levels of B2-microglobulin and elevated levels of DNAemia were observed more often in fetuses diagnosed with severe brain damage.5 In fetuses with mild brain ultrasound abnormalities or extracerebral abnormalities, fetal blood sampling could potentially reduce uncertainty about the prognosis.5 How- ever, in fetuses with normal imaging, where the risk of moderate to severe sequelae is low, do these parameters provide valuable information for counseling parents? The evidence is still limited and there are no data demonstrating that the onset of ultrasound brain abnormalities in the third trimester can be predicted by fetal blood parameters. There is the potential for increasing the rate of termination of pregnancy without diagnostic con rmation of fetal sequelae. Furthermore, valacyclovir reduces the risk of maternal-fetal transmission of CMV and is now recom- mended by guidelines.6 We do not know how the antiviral therapy may affect the values of CMV DNA, platelets, and B2-microglobulin in fetal blood, which makes their use even more complex. We believe that data are insuf cient to recommend routine use of cordocentesis in evaluation for congenital CMV infection and rather, it should be performed on an individual basis, considering the risks and diagnostic limitations.