A Case of Severe Hemolytic Disease of the Newborn Caused by Anti-Di^a and SLC4A1 Gene Analysis in the Family

Excerpt

A 1-day-old newborn with extreme hyperbilirubinemia was found in Dalian Children’s hospital, whose total bilirubin surged to 466 µmol/L (27.3 mg/dL) within 4 h after birth. Coomb’s test (anti-IgG) of the newborn was strongly positive, while initial antibody screening test (Blood and Biological Medicine, Shanghai, China) was negative. The mother had an 11-years-old daughter and a severe hemolytic disease of the newborn (HDN) was suspected in this case. The blood type of the newborn was A, Rh CcDee and her mother was A, Rh CcDEe, so ABO and Rh HDN were excluded. In order to confirm the cause of the hyperbilirubinemia in this newborn, more serological and genetic tests were performed for further investigation in Dalian Blood Center. No antibody was identified in the plasma of both the newborn and her mother by using Makropanel 16 (Sanquin Reagents, Amsterdam, Netherlands). However, anti-Di^a antibody was identified in the newborn’s plasma and eluate of her red blood cells by using Panel Cells 10 (Blood and Biological Medicine, Shanghai, China). An antibody titer of 128 was detected using Di (a+) red cells by the method of double dilution. As inaccessibility of monoclonal anti-Di^a and anti-Di^b reagent, for further investigation, we performed polymerase chain reaction-sequence based typing (PCR-SBT) to genotype DI*A (Di^a) and DI*B (Di^b) [1]. Sequencing for exon 19 of SLC4A1 gene in the family is illustrated in Fig. 1.

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