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We think you have liked this presentation. If you wish to download it, please recommend it to your friends in any social system. Share buttons are a little bit lower. Thank you! Published by Quinn Bickford Modified over 5 years ago. Reconhecimento do Ag 4. Abstract Objective: Although anti-D prophylaxis has greatly reduced the rate of Rh-immunization, there remain women who sensitize during or after pregnancy because of inadequate prophylaxis.

The purpose of this study was to compare adherence to prophylaxis recommendations for antenatal and postnatal anti-D immunoglobulin administration. Methods: We conducted a retrospective cohort study of all pregnancies recorded at the Royal Victoria Hospital between and to determine the rates of antenatal and postnatal prophylaxis in Rh D -negative women.

We compared adherence to anti-D prophylaxis recommendations between our institution's physician-dependent antenatal approach and the protocol-based postpartum approach. Results: Antenatal administration was analyzed in pregnancies in eligible Rh-negative women. Among these women, Conclusion: Unlike hospital-based protocol-dependent systems, physician-dependent systems for antenatal anti-D prophylaxis remain subject to errors of omission.

A more standardized system is needed to ensure effective antenatal prophylaxis. Memorial Blood Center of Minneapolis, Minnesota. Abstract Most women have only very small amounts of fetal blood in their circulations following pregnancy and delivery: the volume is less than 0. FMH of 30 mL or more occurs in just 3 of women. When the FMH was mL or more, 15 of 41 infants did not survive Rh-negative women with FMH of more than 30 mL of Rh-positive whole blood are at increased risk of Rh immunization, and thus the outcome of their future pregnancies also may be affected.

ABO-compatible fetal red cells that have entered the maternal circulation have a life span similar to that of adult cells. ABO-incompatible fetal red cells may be cleared rapidly, but in some cases they circulate for weeks. Most FMHs of 30 mL or more occur before labor, delivery, or cesarean section. The majority occur with minimal clinical signs and symptoms in apparently normal pregnancies. The identification of postpartum Rh-negative women who have 30 mL or more of Rh-positive fetal blood in their circulation is important so that sufficient RhIG for immune suppression can be administered.

It appears that more than one-half of women with FMH of 30 mL or more would not be identified if protocols were adopted to test only women in pregnancies considered to be at high risk. Fetomaternal hemorrhage in normal vaginal delivery and in delivery by cesarean section. Determination of these variables would enable optimalization of guidelines for D alloimmunization prophylaxis.

FMH was assessed by flow cytometry. Contrarily, only rarely does greater FMH occur and delivery by cesarean section does not present a risk factor. Potential sources of bias were systematically identified using bias checklists, and their impact and uncertainty were quantified using expert opinion. Study results were adjusted for biases and combined, first in a random-effects meta-analysis and then in a random-effects meta-regression analysis. After adjusting for these, the pooled odds ratio for sensitisation was estimated as 0.

A meta-regression analysis was performed, which used the data available from the ten anti-D prophylaxis studies to inform us about the relative effectiveness of three licensed treatments. All three licensed dose regimens are expected to be effective. Abstract Objective. The aim of the study was to determine the kinetic profile and duration of detectable levels of anti-D. Prospective observational study. Antenatal outpatient clinic.

Serial plasma anti-D quantitations following antenatal administration of anti-D immunoglobulin were performed using flow cytometry. Kinetic profiles for anti-D levels were generated from the concentration values at predetermined sampling time points. The half-lives were calculated by linear regression analysis. Main outcome measures.

Time vs. The half-life varied between individuals, with a median of 23 days. We found detectable levels of anti-D IgG within two weeks of parturition in 11 of 12 women. The preparation of anti-D immunoglobulin used in the present study, if administrated in pregnancy week , is associated with detectable levels of anti-D in most women at the time of delivery. Although the half-time is 23 days, it is uncertain whether all mothers have adequate anti-D concentrations at term. Alternative strategies may be evaluated in the future, with repeated administration of antenatal prophylaxis at term rather than conventional postpartum administration of anti-D.

Red-cell and platelet alloimmunisation in pregnancy. Abstract The management of red-cell alloimmunisation has been revolutionised by the widespread use of anti-D administration for mothers who are rhesus negative, and the availability of non-invasive, ultrasound-based techniques for reliable detection of moderate-to-severe fetal anaemia.

With reduced frequency of alloimmunisation to the D antigen, antibodies to c and Kell antigen are increasingly responsible for red-cell alloimmunisation. Ultrasound-based, non-invasive diagnosis is now so reliable that invasive techniques are sparingly used to detect significant fetal anaemia.

Treatment of fetal anaemia using ultrasound-guided intravascular transfusions is highly successful. Advances in molecular biology have led to the successful determination of fetal blood group using free fetal DNA from maternal blood. This development is highly likely to allow use of anti-D in only those pregnant women carrying rhesus-positive fetuses.

Sensitisation to non-D group antibodies continues to occur owing to the lack of available prophylaxis for other blood-group antigens. Serologic and molecular characterization of D variants in Brazilians: impact for typing and transfusion strategy.

Abstract Rh discrepancies are a problem during routine testing because of partial D or weak D phenotypes. Panels of monoclonal antibodies MoAb are being developed to identify D variants such as partial D and weak D when there are anomalous D typing results; however, molecular characterization offers a more specific classification of weak and partial D.

The weak D and partial D phenotypes are caused by many different RHD alleles encoding aberrant D proteins, resulting in distinct serologic phenotypes and the possibility of anti-D immunization. We evaluated currently used serologic methods and reagents to detect and identify D variants and correlated the results with molecular analyses.

A total of blood samples from Brazilian blood donors and patients with discrepant results in routine D typing were analyzed. In total, Among weak D samples, 76 weak D type 1 Among the partial D samples, 49 type 4. Our results showed that the use of different methods and anti-D reagents in the serologic routine analysis revealed D variants that can be further investigated.

Molecular methods can help to differentiate between partial D and weak D and to characterize the weak D types, providing additional information of value in the determination of D phenotypes. This distinction is important for optimized management of D— RBC units and for the prevention of anti-D—related hemolytic disease of the fetus and newborn.

Epub Jul Partial D phenotypes and genotypes in the Chinese population. Although the molecular basis underlying the partial D phenotype has been investigated in several races, data from Chinese populations are rare.

Samples with partial D phenotype were determined by commercial monoclonal anti-D panels and molecular methods. Blood samples with discrepant results of serologic and molecular methods were further investigated by polymerase chain reaction PCR with sequence-specific primers and nucleotide sequencing of RHD exons.

The detection of antibodies was performed. Molecular typing revealed five different known aberrant alleles as well as four new RHD alleles. As described previously, DVI represented the most frequent partial D type in China with a total of 36 samples. However, discrepant results were observed in four DVI samples with serotyping and genotyping i. New laboratory procedures and Rh blood type changes in a pregnant woman. New molecular blood-typing methods have identified variant D antigens, which may be reported as Rh-positive or Rh-negative depending on the laboratory method.

We describe a case illustrating the effect of the new laboratory methods on a woman's candidacy for Rh immune globulin and present recommendations for interpreting the new test results. CASE: A year-old woman presented for management of her third pregnancy. During her first pregnancy, she was typed as Rh-positive "D" and did not receive Rh immune globulin.

During her second pregnancy, she was typed as Rh-negative, in accordance with revised Rh-typing procedures. Anti-D antibody was detected. During her third pregnancy, she was genotyped as a partial D antigen, which was reported as Rh-negative. Detection of fetomaternal hemorrhage. Abstract The prevention of Rhesus D alloimmunization through Rh immune globulin RhIg administration is the major indication for the accurate detection and quantification of fetomaternal hemorrhage FMH.

In the setting of D incompatibility, D-positive fetal cells can sensitize the D-negative mother, resulting in maternal anti-D alloantibody production.

These anti-D alloantibodies may lead to undesirable sequelae such as hemolytic disease of the newborn HDN. Since the widespread adoption of FMH screening and RhIg immunoprophylaxis, the overall risk of Rh alloimmunization and infant mortality from HDN has substantially decreased. The rosette screen, the initial test of choice, is highly sensitive in qualitatively detecting 10 mL of fetal whole blood in the maternal circulation.

As the screen is reliant on the presence of the D antigen to distinguish fetal from maternal cells, it cannot be used to detect FMH in D-positive mothers or in D-negative mothers carrying a D-negative fetus. The Kleihauer-Betke acid-elution test, the most widely used confirmatory test for quantifying FMH, relies on the principle that fetal RBCs contain mostly fetal hemoglobin HbF , which is resistant to acid-elution whereas adult hemoglobin is acid-sensitive.

Although the Kleihauer-Betke test is inexpensive and requires no special equipment, it lacks standardization and precision, and may not be accurate in conditions with elevated F-cells. Anti-HbF flow cytometry is a promising alternative, although its use is limited by equipment and staffing costs. Hematology analyzers with flow cytometry capabilities may be adapted for fetal cell detection, thus giving clinical laboratories a potentially attractive automated alternative for quantifying FMH.

Noninvasive prenatal RHD genotyping by real-time polymerase chain reaction using plasma from D-negative pregnant women. We performed real-time polymerase chain reaction on fetal DNA derived from maternal plasma to determine fetal Rh status. All 3 RHD exon sequences were detected in 68 of 72 mothers of D-positive infants.

The presence of fetal DNA in mothers of D-negative infants was confirmed in all 10 boys and in 14 of 16 girls.



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Doença Hemolítica Perinatal

Cynthia Amaral M. Moreira III. Todos os pacientes receberam fototerapia antes do procedimento. Bowman J. The management of hemolytic disease in the fetus and newborn. Semin Perinatol ;


Doença Hemolítica Perinatal — Caso Clínico

Stephany Silva flag Denunciar. Hadley A. The Alloimune disorders of pregnancy. Cambridge University Press, New York




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