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What is 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? and explain in detail?
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.