Cytomegalovirus DNA detection on Guthrie cards: A useful method to identify hearing loss cases due to congenital infection

The significance of congenital cytomegalovirus (CMV) infection as a cause of hearing loss (HL) is difficult to evaluate because of problems in diagnosing the infection when a child is found deaf. In this study, a test relying upon PCR amplification of CMV DNA extracted from stored Guthrie cards has been applied to 42 cases of HL (age: 4 days to 2 months) identified in the period 1993-1999. The test was positive in 5 cases: one regarded an infant with a congenital CMV disease, two were premature babies, and two were full-term babies with no known risk factor. These results confirm the usefulness of the test on Guthrie cards in the assessment of the etiology of HL. It is conceivable that it might lead to discover a higher rate of congenital CMV linked cases. This in turn might suggest the advisability of prophylactic interventions.