title: Fetal and neonatal anemia associated with anti-Jr(a) : a case report showing a poorly hemolytic mechanism.
abstract: Although recently published case reports suggest the significance of Jr(a) alloimmunization in the obstetric setting, the involved mechanism still remains unclear. Here we report a case of severe fetal and neonatal anemia associated with anti-Jr(a) alloimmunization, which was successfully managed using Doppler assessment of peak systolic velocity of the fetal middle cerebral artery (MCA-PSV). A Japanese woman with anti-Jr(a) (titer 1024) was referred to our department at 20 weeks' gestation. As fetal MCA-PSV exceeded 1.5 multiple of median, labor was induced and a female neonate of 1998 g was delivered vaginally at 33 weeks and 5 days of gestation. The infant's hematocrit and hemoglobin levels were 25.4% and 82 g/L, respectively, but her total bilirubin level (15 µmol/L; 0.9 mg/dL) and reticulocyte counts (4.5%) were low. During the course, the infant showed no apparent signs of hemolysis. Jr(a) alloimmunization should be recognized as a possible cause of fetal anemia with no direct hemolytic process.
authors.affiliation: Department of Obstetrics and Gynecology, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Sasamoto
authors.forename: Takuji
authors.initials: T
authors.lastname: Tomimatsu
authors.forename: Keisuke
authors.initials: K
authors.lastname: Nagamine
authors.forename: Machiko
authors.initials: M
authors.lastname: Oshida
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Kashiwagi
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Koyama
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kanagawa
authors.forename: Hitomi
authors.initials: H
authors.lastname: Arahori
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Tomiyama
authors.forename: Tadashi
authors.initials: T
authors.lastname: Kimura
mesh_terms: D000328:Adult; D000751:Anemia, Neonatal / Q000000981:diagnostic imaging* / Q000276:immunology* / Q000503:physiopathology; D001783:Blood Flow Velocity; D001789:Blood Group Antigens / Q000032:analysis; D005260:Female; D005323:Fetal Monitoring; D006801:Humans; D007231:Infant, Newborn; D007518:Isoantibodies / Q000032:analysis*; D007564:Japan; D007751:Labor, Induced; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000196:embryology / Q000503:physiopathology; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011263:Pregnancy Trimester, Third; D047928:Premature Birth; D016216:Ultrasonography, Prenatal; D055815:Young Adult
chemical_list: D001789:Blood Group Antigens; D007518:Isoantibodies