Search

Background: Because antibody identification is labor-intensive, facilities with high volume and/or marginal technical support could benefit from partial automation., Study Design and Methods: After a validation study of automated solid-phase red cell (RBC) adherence assay (SPRCA; Galileo, Immucor) compared to tube polyethylene glycol antiglobulin antibody identification method (t-PEG), we evaluated Galileo followed by select RBC panels by t-PEG. Of 298 consecutive samples in which antibody identifications were performed in a 2-month period, 160 samples were examined by both Galileo and t-PEG., Results: There were concordant results between Galileo and t-PEG in 120 of 160 (75%) samples including cases with identical alloantibody identification (n = 99), panagglutinin (n = 9), and negative results (n = 12). Of the samples in which alloantibodies were identified, 99 of 108 (91.7%) were identical. In 9 samples with discrepant antibody identifications, 2 samples showed alloantibody specificity by Galileo (possible anti-K and anti-Jk(b)) but were negative by t-PEG. These antibodies were identifiable by t-PEG in subsequent samples. One sample showed anti-E by Galileo, while t-PEG revealed anti-Fy(a) and -E. Five samples showed alloantibody specificity by t-PEG and nonspecific reactivity or panagglutinin by Galileo. These included samples with anti-C (n = 2), anti-E (n = 2), and anti-Fy(a) (n = 1). One sample showed anti-E by t-PEG but was negative by Galileo. Galileo found a panagglutinin in 23 samples and nonspecific reactivity in 22 samples, whereas t-PEG found a panagglutinin in 12 samples but no nonspecific reactivity., Conclusions: Automated Galileo solid-phase red cell adherence assay can be a useful adjunct for antibody identification, although it detects more nonspecific reactivity than does t-PEG.

Background: D-RBCs are produced by a rare gene that fails to encode for CcEe. Such persons may produce an antibody (Ab) of complex specificity such as anti-Rh17 (Hro). The anti-Rh 17 Ab may cross the placenta and cause severe hydrops fetalis. Case Report: A 34-year old pregnant woman G2P1001 was found to have a high-titer IgG Ab against high-frequency antigen with negative DAT. Further investigation showed her RBCs are D-. Her mother's and father's RBC phenotypes are O, D+ c+ e+ and A, D+, C+ e+ respectively. Her parents are unrelated. Her husband's RBC phenotype is O, D+C+c+E+e+. Sensitization presumably resulted from transfusion of two units of blood after her first delivery. Prenatal ultrasonography showed polyhydramnios and double bubble consistent with duodenal atresia. Amniocentesis at 31 weeks disclosed zone III OD at 450 on Liley graph. Hydrops fetalis developed two days prior to cesarean section. Two courses of betamethasone were given prior to delivery. The baby, delivered at 33 weeks with birth weight of 2121 g, had severe hydrops fetalis and was intubated immediately. Apgar scores were 4 and 7 at 1 and 5 min, respectively. He received surfactant and mechanical ventilation until day 19, and oxygen until day 25. Initial Hb was 6.9g/dl, platelets 100,000/ul, bilirubin 7.1/1.0 mg/ dl, and RBC type is O, C+D+e+. Two exchange transfusions (EXT) were done: a partial EXT and double volume EXT with D—blood reconstituted with FFP. Ab titer decreased from 1:256 after EXT to 1:16 at 5 weeks of life, with an estimated t1/2 of 6.7 days. Mixed jaundice was treated first with phototherapy, IVIG, and phenobarbital. Because of limited availability of D— blood, erythropoietin was initiated immediately. Cardiovascular complications included systemic hypotension, pulmonary hypertension, and patent ductus arteriosus which required surgical ligation. Laparotomy disclosed a preampullary duodenal atresia with malrotation; a duodenoduodenostomy and appendectomy were done. Persistent cholestatic jaundice was treated with phenobarbital, ursodiol, elementary diet (with MCT oil), and liposoluble vitamins. Conclusions: This is a case of severe hydrops fetalis due to hemolytic disease associated with D— possible de novo mutation, accompanied with duodenal atresia, and treated successfully with a combination of D— RBC and erythropoietin. [ABSTRACT FROM AUTHOR]