A rare case of hemolytic disease of newborn due to weak D (D unknown) antigen in child

Obstetric and Newborn Weak D-Phenotype RBC Testing and Rh Immune Globulin Management Recommendations: Lessons From a Blinded Specimen-Testing Survey of 81 Transfusion Services

CONTEXT.—

Modern RHD genotyping can be used to determine when patients with serologic weak D phenotypes have RHD gene variants at risk for anti-D alloimmunization. However, serologic testing, RhD interpretations, and laboratory management of these patients are quite variable.

OBJECTIVE.—

To obtain interlaboratory comparisons of serologic testing, RhD interpretations, Rh immune globulin (RhIG) management, fetomaternal hemorrhage testing, and RHD genotyping for weak D-reactive specimens.

DESIGN.—

We devised an educational exercise in which 81 transfusion services supporting obstetrics performed tube-method RhD typing on 2 unknown red blood cell challenge specimens identified as (1) maternal and (2) newborn. Both specimens were from the same weak D-reactive donor. The exercise revealed how participants responded to these different clinical situations.

RESULTS.—

Of reporting laboratories, 14% (11 of 80) obtained discrepant immediate-spin reactions on the 2 specimens. Nine different reporting terms were used to interpret weak D-reactive maternal RhD types to obstetricians. In laboratories obtaining negative maternal immediate-spin reactions, 28% (16 of 57) performed unwarranted antiglobulin testing, sometimes leading to recommendations against giving RhIG. To screen for excess fetomaternal hemorrhage after a weak D-reactive newborn, 47% (34 of 73) of reporting laboratories would have employed a contraindicated fetal rosette test, risking false-negative results and inadequate RhIG coverage. Sixty percent (44 of 73) of laboratories would obtain RHD genotyping in some or all cases.

CONCLUSIONS.—

For obstetric and neonatal patients with serologic weak D phenotypes, we found several critical problems in transfusion service laboratory practices. We provide recommendations for appropriate testing, consistent immunohematologic terminology, and RHD genotype-guided management of Rh immune globulin therapy and RBC transfusions.

RhD alloimmunization by DEL variant missed in donor testing

INTRODUCTION

Exposure to normal or variably expressed RhD antigens in an antigen-negative individual can elicit an immune response and lead to the formation of clinically significant anti-D alloantibodies. We present the case of anti-D alloimmunization by DEL variant missed in routine blood donor screening.

MATERIAL AND METHODS

Blood donors were typed for D antigen using the direct serologic micromethod. Nonreactive samples were confirmed in the indirect antiglobulin method with an IgM/IgG anti-D monoclonal reagent. Genomic DNA was extracted using a commercial QIAamp DNA Blood Mini kit on the QIAcube device (Qiaqen, Germany). RHD genotyping was performed using the PCR-SSP genotyping kits- Ready Gene D weak, Ready Gene D weak screen, Ready Gene CDE, and Ready Gene D AddOn (Inno-Train, Germany). Unidentified alleles were sent for DNA genome sequencing.

RESULTS

After identifying DEL positive blood units in RhD negative blood donor pool, a look-back study was performed to determine if their previous donations caused alloimmunization in recipients. Out of 40 D negative recipients, one developed anti-D alloantibody after 45 days. The patient did not receive other RhD positive blood products. Blood donor typed D negative in direct and indirect agglutination method. RHD screening was positive, but RHD genotyping and DNA sequencing showed no mutation indicating the normal genotype.

CONCLUSION

Currently used methods in RHD genotyping are insufficient to identify many variant alleles, especially intronic variations. We suggest additional gene investigation including yet unexplored regions of regulation and intron regions to justify our serological finding.

The Improvement Effect of Different Doses of Gamma Globulin on the Disease Condition of Infants with Hemolytic Disease of Newborn and Their Effects on Immune Factors in Serum

BACKGROUND

To explore the effect of different doses of Gamma Globulin (GG) on the condition of children with Hemolytic Disease of Newborn (HDN) and the influence of immune factors in serum.

METHODS

Overall, 180 infants with hemolytic disease of newborn in the People's Hospital of Zhangqiu Area, Jinan, China from April 2016 to August 2018 were divided into group A (88 cases) and group B (92 cases). Group A was given intravenous low-dose GG on the basis of phototherapy, and group B was given intravenous high-dose GG on the basis of phototherapy. The level of serum total bilirubin of the infants, the levels of CD3+, CD4+, CD8+, IgA, IgG and IgM of the infants, the time of jaundice disappearance and the length of hospital stay, hemoglobin and reticulocyte levels were recorded before treatment and after treatment. The number and condition of adverse reactions were recorded.

RESULTS

After treatment, the levels of TBiL, hemoglobin and reticulocyte, the time of jaundice disappearance and hospital stay in group B were significantly lower than those in group A. The level of immune cells in group B was significantly higher than that in group A after 7 days of treatment, and the levels of IgA / IgG / IgM in group B were significantly higher than those in group A after 28 days of treatment.

CONCLUSION

Intravenous high-dose GG has a better effect on the condition of neonatal hemolytic disease patients, and more effectively improve the immune function of children.