RT Journal Article SR Electronic T1 Notorious anti-Jk3 in a pregnant woman JF American Society for Clinical Laboratory Science JO Clin Lab Sci FD American Society of Chemistry and Laboratory Science SP 78 OP 82 DO 10.29074/ascls.27.2.78 VO 27 IS 2 A1 Jator, Eleanor K. YR 2014 UL http://hwmaint.clsjournal.ascls.org/content/27/2/78.abstract AB This is a case study of a 23-year-old pregnant Polynesian woman with anti-Jk3 identified in her plasma during her third visit to a hospital. This patient, with a history of mild anemia due to β-thalassemia minor and two known transfusion of packed red cells came to an emergency room complaining of severe abdominal cramps. Her hemoglobin during her second hospital visit was 7.5g/dL and her antibody screen was negative. Two units of crossmatch compatible packed cells were transfused with no adverse reaction and she was discharged. Four days post transfusion, she returned to the hospital complaining of back pain and fatigue and she was running a fever (101°F). Her antibody screen was positive, direct antiglobulin testing was also positive and the eluate showed pan-agglutination with a red cell panel. Anti-Jk3 was identified in her plasma by the Red Cross and a delayed transfusion reaction was suspected. As a result, Kidd null crossmatch compatible units were obtained from relatives. The patient was successfully transfused and was discharged with a hemoglobin of 10.1g/dL. The fetus appeared to be unaffected by the antibody. This case reiterates the hard-to-identify characteristics of Kidd antibodies and highlights the need for medical laboratory personnel to be informed on the prevalence of the Kidd null phenotype among various populations. Educating ethnic populations with rare phenotypes and organizing targeted blood drives may increase inventories of these rare blood phenotypes.ABBREVIATIONS: HDFN: Hemolytic disease of the fetus and newborn, IgG: Immunoglobulin G.