Infezione congenita da citomegalovirus e ipoacusia

Abstract

Background - Cytomegalovirus (CMV) infection is the most common of congenital infections, with a prevalence of 0.3-1.2% in industrialized countries and is the most frequent non-genetic cause of permanent hearing loss in children, with an incidence ranging from 0.2 to 2%. Since there is no antenatal therapy or vaccine against CMV and since many patients with congenital CMV (cCMV) do not experience sequelae even in the absence of specific therapy, a universal screening programme has not been established. Current protocols provide test for the detection of cCMV in case of failure at newborn hearing screening. Aim - This article aims to analyze the pros and cons of the different screening approaches for cCMV, through an overview of the topic based on the most recent literature. Materials and Methods - The recent national and international literature on cCMV screening has been examined through a narrative review. Results - As part of the screening and early identification programmes for neonatal hearing loss, current procedures include a search for cCMV on urine or saliva within 3 weeks of life, following a positive result (Refer) at newborn audiological screening. This approach enables to recognize cCMV infection in newborns suffering from isolated hearing loss, which is already present at birth, however it does not allow cases of CMV-related hearing loss occurring in the postnatal period or late in childhood to be recognized. A universal newborn cCMV screening, in conjunction with audiological screening, would have the advantage of identifying all infants infected with cCMV, including 10%-15% of asymptomatic conditions at birth who may develop late hearing loss. One of the major obstacles to the establishment of universal cCMV screening is the unknown cost of its application and a clear understanding of the sensitivity and specificity of the cCMV test. Conclusions - Strategies are needed to identify children with congenital CMV infection at risk for developing late-onset hearing loss. A universal newborn screening to ensure timely recognition of children with cCMV, close audiological surveillance and possible early treatment at the onset of the first hearing symptoms should be provided.