title: Sequence analysis of two variable cytomegalovirus genes for distinction between transfusion- and breast milk-transmitted infections in a very-low-birthweight infant.
abstract: BACKGROUND
  Cytomegalovirus (CMV) infections in very-low-birthweight infants can lead to serious clinical consequences. When CMV-related symptoms occur after transfusion, CMV transmission is often attributed to the transfusion products rather than to breast milk. However, it is sometimes difficult to distinguish between transfusion-transmitted and breast milk-transmitted CMV infections.
  
  
  METHODS
  A patient was born at 27 gestational weeks with a weight of 689 g. He was transfused with leukoreduced red blood cells (LR-RBCs), which were later found to be CMV seropositive and CMV DNA positive. He was also fed with CMV DNA-positive breast milk. Thereafter, he developed CMV disease with thrombocytopenia and jaundice. To determine the route of transmission, we analyzed the sequences of two variable CMV genes, UL139 and UL146, by direct sequence analysis. We also performed deep sequence analysis to determine whether there were polyclonal CMV strains in the LR-RBCs transfused.
  
  
  RESULTS
  CMV DNA sequence-matching rates for the LR-RBCs and the patient's blood were 64.6% for the UL139 gene and 68.6% for the UL146 gene. In contrast, the sequences of these genes in the patient's blood were 100% matched with those in the breast milk. Furthermore, by deep sequence analysis, the CMV strain found in the patient's blood was not detected in the LR-RBCs transfused.
  
  
  CONCLUSIONS
  The results indicate that the pathogenic CMV strain was transmitted through breast milk, which is consistent with the claims that transfusion-transmitted CMV infection due to leukoreduced blood products is uncommon.
authors.affiliation: Central Blood Institute Japanese Red Cross Society, Tokyo.
authors.forename: Naoji
authors.initials: N
authors.lastname: Yamagishi
authors.affiliation: Blood Service Headquarters, Japanese Red Cross Society, Tokyo, Japan.
authors.forename: Yasumi
authors.initials: Y
authors.lastname: Furui
authors.affiliation: Tohoku University School of Medicine.
authors.forename: Syota
authors.initials: S
authors.lastname: Koshinami
authors.affiliation: Tohoku Block Blood Center, Japanese Red Cross Society, Sendai, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Ichijo
authors.affiliation: Miyagi Blood Center, Japanese Red Cross Society, Sendai, Japan.
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Shimizu
authors.affiliation: Central Blood Institute Japanese Red Cross Society, Tokyo.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Hoshi
authors.affiliation: Central Blood Institute Japanese Red Cross Society, Tokyo.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Gotanda
authors.affiliation: Central Blood Institute Japanese Red Cross Society, Tokyo.
authors.forename: Keiko
authors.initials: K
authors.lastname: Miyakawa
authors.affiliation: Central Blood Institute Japanese Red Cross Society, Tokyo.
authors.forename: Shigeharu
authors.initials: S
authors.lastname: Uchida
authors.affiliation: Blood Service Headquarters, Japanese Red Cross Society, Tokyo, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Tadokoro
authors.affiliation: Central Blood Institute Japanese Red Cross Society, Tokyo.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Nagai
authors.affiliation: Central Blood Institute Japanese Red Cross Society, Tokyo.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Satake