title: Hemolytic disease of the newborn associated with anti-Jra alloimmunization in a twin pregnancy: the first case report in Korea.
abstract: Jr(a) is a high-frequency antigen found in all ethnic groups. However, the clinical significance of the anti-Jr(a) antibody has remained controversial. Most studies have reported mild hemolytic disease of the newborn and fetus (HDNF) in Jr(a)-positive patients. Recently, fatal cases of HDNF have also been reported. We report the first case of HDNF caused by anti-Jr(a) alloimmunization in twins in Korea. A 33-yr-old nulliparous woman with no history of transfusion or amniocentesis was admitted at the 32nd week of gestation because of vaginal bleeding caused by placenta previa. Anti-Jr(a) antibodies were detected in a routine laboratory examination. An emergency cesarean section was performed at the 34th week of gestation, and 2 premature infant twins were delivered. Laboratory examination showed positive direct antiglobulin test and Jr(a+) phenotype in the red blood cells and the presence of anti-Jr(a) antibodies in the serum in both neonates. The infants underwent phototherapy for neonatal jaundice; this was followed by conservative management. They showed no further complications and were discharged on the 19th postpartum day. Preparative management to ensure the availability of Jr(a-) blood, via autologous donation, and close fetal monitoring must be performed even in cases of first pregnancy in Jr(a-) women.
authors.affiliation: Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Hyungsuk
authors.initials: H
authors.lastname: Kim
authors.forename: Min-Jeong
authors.initials: MJ
authors.lastname: Park
authors.forename: Tae-Jung
authors.initials: TJ
authors.lastname: Sung
authors.forename: Ji Seon
authors.initials: JS
authors.lastname: Choi
authors.forename: Jungwon
authors.initials: J
authors.lastname: Hyun
authors.forename: Kyoung Un
authors.initials: KU
authors.lastname: Park
authors.forename: Kyou-Sup
authors.initials: KS
authors.lastname: Han
mesh_terms: D000328:Adult; D001789:Blood Group Antigens / Q000276:immunology; D001787:Blood Group Incompatibility; D004200:Diseases in Twins / Q000175:diagnosis / Q000276:immunology*; D004899:Erythroblastosis, Fetal / Q000175:diagnosis* / Q000276:immunology; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007519:Isoantigens / Q000276:immunology; D007567:Jaundice, Neonatal / Q000150:complications / Q000276:immunology / Q000628:therapy; D008297:Male; D010641:Phenotype; D010789:Phototherapy; D011247:Pregnancy; D011250:Pregnancy Complications, Hematologic / Q000175:diagnosis / Q000276:immunology*; D014427:Twins
chemical_list: D001789:Blood Group Antigens; D007519:Isoantigens