title: Successful treatment of extremely severe fetal anemia due to anti-Jra alloimmunization.
abstract: BACKGROUND
  Although Jr(a) hemolytic disease of the newborn (HDN) is generally considered to be mild, we encountered a case of anti-Jr(a) alloimmunization hydrops fetalis due to extremely severe fetal anemia that required aggressive intrauterine treatment.
  
  
  METHODS
  A Japanese woman developed hydrops fetalis at the 29th week of gestation. Blood examination was highly positive for anti-Jr(a) antibodies. Cordocentesis demonstrated that the fetus had anti-Jr(a) antibodies and the lowest fetal hemoglobin concentration was 2.3 g/dl. After a total of four intravascular transfusions, fetal hydrops improved and a healthy girl of 2,120 g was delivered at the 35th week of gestation. The initial neonatal hemoglobin concentration at birth was 7.2 g/dl. After two straight transfusions, the infant's anemia did not worsen. Anti-Jr(a) antibodies became negative without developing hyperbilirubinemia.
  
  
  CONCLUSIONS
  The incidence of Jr(a) negativity can lead to underestimation of the risk of Jr(a) alloimmunization. This case shows that anti-Jr(a) alloimmunization may cause HDN and hydrops fetalis.
authors.affiliation: Department of Perinatology, National Cardiovascular Center, Suita, Osaka, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Ishihara
authors.forename: Shigeki
authors.initials: S
authors.lastname: Miyata
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Chiba
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kawai
mesh_terms: D000328:Adult; D000740:Anemia / Q000276:immunology / Q000628:therapy*; D001789:Blood Group Antigens / Q000276:immunology*; D001787:Blood Group Incompatibility / Q000150:complications*; D001805:Blood Transfusion, Intrauterine; D005260:Female; D005312:Fetal Blood / Q000737:chemistry; D005315:Fetal Diseases / Q000276:immunology / Q000628:therapy*; D005865:Gestational Age; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D015160:Hydrops Fetalis / Q000276:immunology / Q000628:therapy; D007518:Isoantibodies / Q000097:blood; D011247:Pregnancy; D011256:Pregnancy Outcome
chemical_list: D001789:Blood Group Antigens; D006454:Hemoglobins; D007518:Isoantibodies