Breast milk transmitted cytomegalovirus infection among preterm infants with birth weight ≤1 500 g: a clinical study

Abstract

Objective To investigate the incidence and clinical presentation of breast milk transmitted cytomegalovirus (CMV) infection among preterm infants with birth weight ≤1 500 g. Methods Preterm infants enrolled in this study met the following inclusion criteria: birth weight ≤1500 g, fed with CMV-positive breast milk and admitted into Neonatal Intensive Care Unit of Children's Hospital of Fudan University within 72 hours after birth from October 2015 to July 2016. And those with congenital digestive tract malformation or congenital CMV infection were excluded. Breast milk and infants' urine samples were regularly screened for CMV DNA by fluorescent quantitative polymerase chain reaction. Symptoms and laboratory findings in infants with CMV infection transmitted via breast milk were documented and analyzed. Differences in relevant parameters were analyzed using Chi-square test, Fisher's exact test, t test or Mann-Whitney U test where appropriately. Results Sixty preterm infants breastfed with CMV DAN-positive milk were recruited. Among them, 19 (31.7%) developed breast milk-acquired CMV infection as their urine samples were positive for CMV DNA, while the others were negative for CMV DNA (infected group: n=19; non-infected group: n=41). The average CMV copies in breast milk, gestational age and birth weight of the infected group were all significantly higher than those of the non-infected group [3.76 (3.18-4.50) vs 3.47 (3.00-4.88) Log10 copies/ml, Z=-2.042; (30.4±2.1) vs (28.4±2.3) weeks, t=3.175; 1 290 (750-1 500) vs 1 110 (575-1 480) g, Z=-2.837; all P 0.05]. Four infants (21.1%, 4/19) had severe organ damage and/or positive IgM antibodies to CMV in serum, and were treated with antiviral therapy. Two had mild symptoms and were not given antiviral therapy. All of the six symptomatic infants were followed-up for one to six months, during which time the complete blood cell count and results of biochemical test and fundus examination were back to normal. Conclusions The incidence of breast milk-acquired CMV infection among preterm infants with birth weight ≤ 1 500 g was 31.7%, and no severe symptoms were reported in this study. Key words: Cytomegalovirus infections; Infectious disease transmission, vertical; Breast feeding; Infant, premature