title: Current incidence of clinical kernicterus in preterm infants in Japan.
abstract: Clinical kernicterus in preterm infants has recently been reported in Japan, diagnosed on the basis of clinical findings during the neonatal and infancy periods. We investigated the incidence of clinical kernicterus in preterm infants <30 weeks gestational age (GA) based on a nationwide survey conducted in 233 certified educational facilities for neonatologists. The numbers of infants admitted and infants who died within 14 days after birth during 2011, and the number of infants who subsequently developed clinical kernicterus, were recorded. A total of 2720 infants were analyzed, representing 59% (2720/4623) of all preterm live births <30 weeks GA in Japan in 2011. Of these, 159 (5.8%) died within 14 days after birth, similar to the national rate. Five infants developed clinical kernicterus in infancy (5/2720, 0.18%). The current incidence of clinical kernicterus in Japan is therefore estimated at 1.8 per 1000 live births <30 weeks GA.
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe.|Japan Neonatal Jaundice Study Group, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Morioka
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe.|Japan Neonatal Jaundice Study Group, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Nakamura
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe.|Japan Neonatal Jaundice Study Group, Japan.
authors.forename: Tsubasa
authors.initials: T
authors.lastname: Koda
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe.|Japan Neonatal Jaundice Study Group, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Yokota
authors.affiliation: Department of Pediatrics, Faculty of Medicine, Kagawa University, Kagawa.|Japan Neonatal Jaundice Study Group, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Okada
authors.affiliation: Department of Pediatrics, Takatsuki General Hospital, Takatsuki.|Japan Neonatal Jaundice Study Group, Japan.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Katayama
authors.affiliation: Department of Pediatrics, Saitama Medical University, Saitama.|Japan Neonatal Jaundice Study Group, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Kunikata
authors.affiliation: Department of Neonatology, Tokyo Metropolitan Children's Medical Center, Tokyo.|Japan Neonatal Jaundice Study Group, Japan.
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Kondo
authors.affiliation: Department of Neonatology, Okayama Medical Center, Okayama.|Japan Neonatal Jaundice Study Group, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Nakamura
authors.affiliation: Department of Pediatrics and Child Health, Nihon University School of Medicine, Tokyo.|Japan Neonatal Jaundice Study Group, Japan.
authors.forename: Shigeharu
authors.initials: S
authors.lastname: Hosono
authors.affiliation: Department of Pediatrics, Faculty of Medicine, Kagawa University, Kagawa.|Japan Neonatal Jaundice Study Group, Japan.
authors.forename: Saneyuki
authors.initials: S
authors.lastname: Yasuda
authors.affiliation: Department of Pediatrics, Akashi Medical Center, Akashi.|Japan Neonatal Jaundice Study Group, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Yokoyama
authors.affiliation: Osaka Developmental Rehabilitation Center, Osaka.|Japan Neonatal Jaundice Study Group, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Wada
authors.affiliation: Department of Pediatrics, Faculty of Medicine, Kagawa University, Kagawa.|Japan Neonatal Jaundice Study Group, Japan.
authors.forename: Susumu
authors.initials: S
authors.lastname: Itoh
authors.affiliation: Osaka Developmental Rehabilitation Center, Osaka.|Japan Neonatal Jaundice Study Group, Japan.
authors.forename: Masahisa
authors.initials: M
authors.lastname: Funato
authors.affiliation: Kibi International University, Takahashi.|Japan Neonatal Jaundice Study Group, Japan.
authors.forename: Yoshitada
authors.initials: Y
authors.lastname: Yamauchi
authors.affiliation: Aijinkai Rehabilitation Hospital, Takatsuki.|Japan Neonatal Jaundice Study Group, Japan.
authors.forename: Yong Kye
authors.initials: YK
authors.lastname: Lee
authors.affiliation: Department of Pediatrics, Kakogawa West Municipal Hospital, Kakogawa.|Japan Neonatal Jaundice Study Group, Japan.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Yonetani
mesh_terms: D005260:Female; D005865:Gestational Age; D006801:Humans; D015994:Incidence; D007223:Infant; D007226:Infant Mortality / Q000639:trends; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases / Q000453:epidemiology*; D007564:Japan / Q000453:epidemiology; D007647:Kernicterus / Q000453:epidemiology*; D008297:Male; D012189:Retrospective Studies; D011795:Surveys and Questionnaires; D015996:Survival Rate / Q000639:trends
keywords: Japan; incidence; kernicterus; preterm infant