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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
In a neonate with "classic" symptoms of congenital cytomegalovirus (CMV) infection, which one of the following tests would be most useful in establishing a diagnosis?
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The correct answer is  CMV IgM titre on neonate's serum at bih and at 1 month of age is useful in establishing a diagnosis in a neonate. The results should indicate a rise in IgM titre. Cytomegalovirus (CMV) is the most common cause of congenital and perinatal viral infections. Measurement of total IgM in the infant's sera at bih is nonspecific and may show false-negative and false-positive reactions.