Evaluation of cytomegalovirus infection in low-birth weight children by breast milk using a real-time polymerase chain reaction assay.

Human Cytomegalovirus (CMV) is the most common cause of intrauterine and perinatal infections worldwide. Postnatal CMV transmission has usually no consequences, but in some cases it may produce disease in preterm infants. Literature reports a broad range of breast milk-acquired CMV infections (5.7-58.6%), which depends on the study's design and the treatment of the milk. To evaluate CMV transmission via breast milk, a prospective study using a real-time PCR assay was performed. One hundred and thirty-one mothers (accounting for 160 children) accepted the participation in the study. Urine samples from the infants and breast milk samples from their mothers were collected at 3, 15, 30, 60, and 90 days after delivery. CMV-DNA in breast milk was analysed by quantitative real-time PCR assay Affigene® CMV Trender (Cepheid, Bromma, Sweden). The breast milk samples from 92 mothers (92 of 131, 70.2%) were positive for CMV by PCR. CMV infection was detected in thirteen children by PCR, and four of them (30.7%) had clinical symptoms. There were not significant differences in morbidity between symptomatic and non- symptomatic patients; nonetheless, the average length of hospitalization in symptomatic children was higher than that of non-symptomatic children (P < 0.05). The rtPCR technique is useful for detection of mothers with high viral loads of CMV-DNA in milk, and might be of help to decide whether to freeze the breast milk in preterm children less than 28 weeks.