Detecção dos anticorpos regulares abo maternos em recém-nascidos pelo método de tipagem sangüínea reversa estendida até fase de antiglobulina humana / Detection of the mother's abo regulars antibodies in newborns by the reverse blood typing

Neste estudo foram definidos os índices de detecção dos anticorpos regulares ABO maternos em recém-nascidos pelo método de tipagem sangüínea reversa estendida até fase de antiglobulina humana (TRAGH) e a relação destes resultados com os achados de outras metodologias envolvidas no diagnóstico da incompatibilidade materno-fetal pelo sistema ABO (IABO). Foram colhidasamostras sangüíneas para análise imuno-hematológica de 38 recém-nascidos com tipo sangüíneo A ou B, apresentando até 30 dias de vida (sem conhecimento prévio dos fenótipos ABO maternos) e realização dos testes de tipagem ABO direta, TRAGH, Coombs direto e eluato-LUI, visando detectar anti-A e/ou anti-B. Os resultados demonstraram que a TRAGH efetuou a detecção dos anticorpos regulares ABO maternos na maioria das amostras analisadas nas quais foram confirmados os casos de IABO (09 de 15 amostras), constituindo-se, mediante a análise conjunta com os demais dados imuno-hematológicos, em um útil parâmetro laboratorial na adequação imunológica do hemocomponente ao receptor ena confirmação diagnóstica de IABO.

In this study were defined the exponents of the detection of mother’s ABO regulars antibodies in newborns by the reverse blood typing extend up to stage of the antihuman globulin method (RTAGH) and the relacion this results with the faind other methods include in the diagnosis of the ABO maternal-fetal incompatibility (IABO). Samples of blood were picked for immunohematology analysis from 38 newborns with the blood type A our B , with until 30 days of life ( without previous knowing of the ABO mother’s types) and make of the ABO typing direct, RTAGH, Coombs direct and elution by freezing tests, purposing the detection of the anti-A and/our anti-B. The results demonstrate with the RTAGH maked the detection of the mother’s ABO regulars antibodies in the most samples analyses with the were confirmated the cases of the IABO (09 of 15 samples), constitute, trough the completeness analyse with too much tests immunohematology, in the useful laboratory information in the imunology adjust of the hemocomponent to the pacient and in the diagnosis of IABO confirmation.

Severe hemolytic disease of the newborn in a group B African-American infant delivered by a group O mother.

Maternal-fetal ABO incompatibility is a common hematological problem affecting the newborn. In general, hemolysis is minimal and the clinical course is relatively benign, rarely causing the escalating levels of hyperbilirubinemia and significant anemia commonly associated with Rh hemolytic disease of the newborn (HDN). The incidence of HDN ranges from one in 150 births to 1:3000 births, depending on the degree of anemia and level of serum bilirubin. The etiology of ABO hemolytic disease of the newborn (ABO-HDN) is complex because anti-A and anti-B antibodies are composed mainly of IgM. Since only IgG antibodies cross the placenta, those pregnant women with high levels of IgG anti-A,B, anti-A, or anti-B with an ABO incompatible fetus will be the ones to give birth to an infant with ABO-HDN. We describe a case of a B/Rh positive term newborn born to an O/Rh negative African-American mother demonstrating aggressive hemolysis and a robust response of the bone marrow. This case was successfully managed with phototherapy and simple RBC transfusion without the need for exchange transfusion.

[Correlation of newborn hemolytic disease with ABO antibodies in sera of pregnant women].

To investigate the relations between morbidity of hemolytic diseases of newborn and ABO antibodies (HDN) in sera of Han and Yao nationality, pregnant women were examined before and after delivery. Antibodies screen, direct antiglobulin test, free antibodies and elution test were all performed. The results indicated that immunologic ABO antibodies of Han people were found in 673 cases out of 1,471 Han pregnant women, and was also found in 28 cases out of 65 Yao pregnant women, and there was no significant difference of incidences between Han and Yao nationality. 31 cases of HDN were found out of 288 newborn in Han and 3 cases of HDN were found out of 25 newborn in Yao, and there was no significant difference between Han and Yao nationalities. The characteristics of HDN in Han nationality were as same as in Yao nationality. In conclusion, the morbidity of HDN in Han and Yao nationalities of Shaoguan area did not showed essential difference, the immunologic ABO antibodies and its titration test, especially, elution test are important for prognosis of HDN.

What's happening? The expanding role of apheresis platelet support in neonatal alloimmune thrombocytopenia: current status and future trends.

Despite some unresolved problems that may be associated with platelet transfusion, such as alloimmunisation, refractoriness, bacterial contamination, and the potential side effects related to the development of some biological response modifiers during storage, platelet therapy remains the most effective treatment for the management and prevention of severe thrombocytopenia and hemorrhage [Seghatchian J, Snyder EL, Krailadsiri P, editors. Platelet therapy: current status and future trends. Amsterdam, The Netherlands: Elsevier; 2000]. This appears to be particularly the case in neonatal alloimmune thrombocytopenia (NAIT), which arises due to an incompatibility of the platelet specific antigens between the pregnant mother and her baby. Over 80% of severe NAIT cases in the Caucasian population occur when the mother and baby differ in their HPA-1 epitope (HPA-1a negative and positive respectively) leading, in 10% of cases, to the production of anti-HPA-1a which can cross the placenta and cause NAIT in utero or post-partum. Anti-HPA-5b is the second most cause of NAIT, although severe cases occur only after the first pregnancy. Clinical manifestations of NAIT vary from mild (petechia and bruises) to severe (intracranial haemorrhage with possible death or life long morbidity). A recent study in Scotland indicated that the cost per case of severe NAIT detected during screening of pregnant women, where anti-HPA-1a is detected for the first time, would amount to $98,771 [Turner M, Bessos H, et al. Prospective epidemiological study of the outcome and cost effectiveness of antenatal screening to detect neonatal alloimmune thrombocytopenia (NAIT) due to anti-HPA-1a. Transfusion, in press. Yet, unlike the case with Rhesus hemolytic disease of the new born, the cost-effectiveness of HPA-1 screening in NAIT remains unresolved, as does the most optimal mode of treatment. Therefore, in the absence of a consensus on the screening and optimal management of NAIT, the availability and provision of HPA-1a/5b negative apheresis platelets based on current practice (transfusionguidelines.org.uk) appear to be a clinically effective treatment in NAIT. In that vein, an increasing number of blood transfusion centres are screening blood donors in order to secure panels of donors for the prompt provision of HPA-1a/5b negative apheresis platelets. However, evidence is also accumulating that while platelets derived from various apheresis technologies currently in use may be equivalent in terms of cellular contents (thus meeting specifications), they may differ in terms of the platelet storage lesion, microvesiculation and the development of platelet-derived cytokines and some other biological response modifiers [Seghatchian J. Platelet storage lesion: the influence of various leukoreduction procedures on generation/retention of some biological response modifiers, microvesiculation, distribution of membrane-bound/soluble Prion and the rate of HLA-CLASS1 release. Trans Apher Sci, in press. This manuscript summarises strategy and progress both in the improvement of apheresis platelet quality and provision in NAIT.