Management Of Alloimmunization Research Articles

Alloimmunization in Pregnancy: Implications for the Fetus and Neonate.

Blood group or red cell alloimmunization occurs when a pregnant patient has produced antibodies to a blood group antigen possessed by the fetus and not possessed by the pregnant patient. Maternal antibodies are usually produced as an immune response to fetal-maternal bleeding or blood product transfusion. Prevention remains the most important strategy to avoid the formation of maternal antibodies or alloimmunization. Maternal alloimmunization may result in transplacental passage of these antibodies into the fetal circulation and the potential for fetal or neonatal hemolysis and anemia. Red cell alloimmunization can result in significant perinatal morbidity and mortality. Management of alloimmunization in pregnant patients should be protocol-driven. Current strategies for assessment and therapies allow for more thorough and less invasive management with risks to mother and fetus.

ACOG Clinical Practice Update: Paternal and Fetal Genotyping in the Management of Alloimmunization in Pregnancy

This Clinical Practice Update clarifies guidance on paternal genotyping and provides new recommendations on the role of noninvasive fetal red blood cell antigen genotyping using cell-free DNA (cfDNA). This document updates Practice Bulletin No. 192, Management of Alloimmunization in Pregnancy (Obstet Gynecol 2018;131:e82–90).

ACOG Practice Bulletin No. 192 Summary: Management of Alloimmunization During Pregnancy.

When any fetal blood group factor inherited from the father is not possessed by the mother, antepartum or intrapartum fetal-maternal bleeding may stimulate an immune reaction in the mother. Maternal immune reactions also can occur from blood product transfusion. The formation of maternal antibodies, or "alloimmunization," may lead to various degrees of transplacental passage of these antibodies into the fetal circulation. Depending on the degree of antigenicity and the amount and type of antibodies involved, this transplacental passage may lead to hemolytic disease in the fetus and neonate. Undiagnosed and untreated, alloimmunization can lead to significant perinatal morbidity and mortality. Advances in Doppler ultrasonography have led to the development of noninvasive methods of management of alloimmunization in pregnant women. Together with more established protocols, Doppler ultrasound evaluation may allow for a more thorough and less invasive workup with fewer risks to the mother and fetus. Prevention of alloimmunization is addressed in another Practice Bulletin ().

Aportación del Doppler de la arteria cerebral media y del genotipado RHD fetal en el manejo de la isoinmunización

ObjectiveTo assess the clinical application of non-invasive methods in the management of alloimmunization from 2006 to 2010. Subjects and methodsSeventy pregnancies with risk of fetal anemia were studied by fetal middle cerebral artery peak systolic velocity (MCA-PSV). The efficacy of MCA-PSV was compared between the first, second and third transfusions. Prenatal testing of fetal RHD blood group using maternal blood was performed in pregnancies followed-up in our center. ResultsFetal blood sampling was performed in 22 pregnancies; of these, fetal transfusion was carried out in 20. Detection rates and the false-positive rate of MCA-PSV in the prediction of severe or moderate fetal anemia were 89% and 15% in pregnancies with no previous transfusions, 100% and 41% in patients with one previous transfusion, and 40% and 24% when more than one transfusion was performed. ConclusionMCA-PSV has high sensitivity when there is one previous fetal transfusion but its specificity is lower.

The prevention and management of alloimmunization in sickle cell disease: the benefit of extended phenotypic matching of red blood cells

The prevention and management of alloimmunization in sickle cell disease: the benefit of extended phenotypic matching of red blood cells

Anti‐Paternal Antibodies by Flow Cytometry in the Management of Alloimmunization on Recurrent Miscarriages

There is no reliable laboratory test available to diagnose immunologically mediated miscarriages. We investigated the clinical significance of maternal anti-paternal leukocyte antibodies by flow cytometry after alloimmunization. The flow cytometry crossmatch (FCXM) was performed in 158 patients with a history of three or more unexplained first-trimester miscarriages without live birth. After negative FCXM patients were immunized, subsequent pregnancy outcomes and FCXM results were followed. Of 112 subsequent pregnancies, 83 of 100 (83.0%) FCXM-positive patients after immunotherapy had successful pregnancy outcomes, whereas seven of 10 (70.0%) FCXM-negative patients had miscarriages (P = 0.0001). The percent live birth ratio was 2.77 (CI, 1.07-7.16; P=0.0001) for FCXM-positive patients compared to FCXM-negative patients. The calculated predictive value showed that 75.6% of FCXM-negative patients would have subsequent miscarriages. Positive FCXM is closely associated with successful pregnancy outcome following immunotherapy. We propose that FCXM might be included in the routine laboratory tests for the management of recurrent miscarriages.