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Antiglobulin Test (antiglobulin + test)
Kinds of Antiglobulin Test Selected AbstractsInfluence of clinical factors on the haemolysis marker haptoglobinEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 3 2006G. F. Körmöczi Abstract Background, Plasma haptoglobin determination is clinically used as parameter for haemolysis. To date, however, the influence of the mode of haemolysis (extravascular vs. intravascular) and of nonhaemolytic conditions on haptoglobin concentration and its reliability as a haemolysis marker remain poorly defined. Materials and methods, In a total of 479 individuals, the influence of haemolytic and nonhaemolytic conditions on plasma haptoglobin levels was investigated. Results, All studied types of haemolytic disease (n = 16) were associated with markedly decreased plasma haptoglobin levels, without significant differences between intravascular vs. predominantly extravascular haemolysis. Diminished haptoglobin values were also observed in patients with liver cirrhosis, which normalized after liver transplantation. In contrast, markedly increased haptoglobin levels were found in patients with inflammation. In patients with haemolysis and a concomitant acute-phase response, however, haemolysis-dependent haptoglobin depletion was not attenuated. Interestingly, patients with a strongly positive direct antiglobulin test or high cold agglutinin titre but no further evidence for haemolysis had normal haptoglobin values. Likewise, anaemia owing to bone marrow failure, acute gastrointestinal or chronic diffuse blood loss, and end-stage kidney disease were associated with normal haptoglobin levels. Conclusions, Plasma haptoglobin depletion is a reliable marker for the instant diagnosis of accelerated red cell destruction irrespective of the site of haemolysis or the presence of inflammation. The capacity of this parameter to predict haemolysis appears to be limited in patients with liver cirrhosis and decreased haptoglobin production only. [source] First case of immune-mediated haemolytic anaemia associated to imatinib mesylateEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 6 2003Marcia C. Zago Novaretti Abstract: Imatinib mesylate is a specific inhibitor of protein tyrosine kinase activity secondary to bcr-abl, mostly indicated for the treatment of patients with Philadelphia chromosome positive chronic myeloid leukaemia (CML). Generally, the undesirable effects of imatinib administration observed in clinical trials were of mild-to-moderate degree, and no haemolysis has been associated with this drug. We report here a case of immune-mediated haemolytic anaemia associated to imatinib mesylate successfully treated with prednisone in a patient with CML. Laboratory investigation showed anaemia [haemoglobin (Hb) of 59 g/L], reticulocyte of 61 × 109/L and a positive direct antiglobulin test. Anti-drug in vitro studies revealed a positive result with gel microcolumn assay by an adsorption mechanism. Seventy-four days after prednisone therapy, the patient's Hb level was of 110 g/L with negative direct antiglobulin test and drug in vitro studies. This case demonstrated that patients treated with imatinib mesylate can present immune-mediated haemolysis and adequate management of this event can be done maintaining the drug and associating corticosteroids. [source] Intravascular haemolysis in a patient on ceftriaxone with demonstration of anticeftriaxone antibodiesINTERNAL MEDICINE JOURNAL, Issue 6a 2008D. Dinesh Abstract Drug-induced haemolytic anaemia can be life threatening. We report a case of ceftriaxone-induced severe haemolytic anaemia in a previously healthy 68-year-old woman. The patient had a positive direct antiglobulin test (anti-C3d positive, anti-immunoglobulin G negative). Serological tests showed ceftriaxone-specific antibodies. The patient recovered after cessation of the drug. This complication may cause milder anaemia and thus be poorly recognized. [source] Therapeutic plasmapheresis as a bridge to liver transplantation in fulminant Wilson diseaseJOURNAL OF CLINICAL APHERESIS, Issue 1 2007Jeffrey S. Jhang Abstract Wilson disease is an autosomal recessive disorder of copper metabolism that leads to the accumulation of copper mainly in the liver, cornea, brain, and kidney. Rarely, Wilson disease can present as fulminant hepatic failure with direct antiglobulin test,negative hemolytic anemia and renal failure. In the absence of liver transplantation, this disease is uniformly fatal because medical therapy is ineffective. This report describes the successful use of plasmapheresis for a patient with fulminant Wilson disease as a bridge to transplantation. Five daily therapeutic plasmapheresis procedures using fresh frozen plasma as a replacement fluid were performed over 6 days. Serum copper, urinary copper excretion, and hemolysis were significantly reduced and renal function improved. The patient's clinical status improved and she remained clinically stable until a liver transplant was possible. Plasmapheresis can be a successful medical treatment in fulminant Wilson disease and should be considered as a therapeutic measure to stabilize a patient by decreasing serum copper, reducing hemolysis, and helping to prevent renal tubular injury from copper and copper complexes until liver transplantation is possible. J. Clin. Apheresis. 22:, 2007 © 2007 Wiley-Liss, Inc. [source] Role of enzyme-treated cells in RBC antibody screening using the gel test: a study of anti-RH1, -RH2, and -RH3 antibodiesJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 2 2007Jocelyne Conne Abstract The role of enzyme-treated cells (ETCs) in red blood cell (RBC) antibody screening has been the subject of controversy, and its place in the clinical routine remains to be determined. In this work, plasma samples containing anti-RH1 (anti-D; N = 10), anti-RH2 (anti-C; N = 10), or anti-RH3 (anti-E; N = 10) antibodies were studied. The samples were diluted in nonbuffered or buffered normal saline, as well as in a pool of AB plasma samples. Titers and scores were determined by means of the gel test, using the indirect antiglobulin test (IAT) as well as ETCs, with R0r, r,r, or r,r test cells. Our results showed that compared to the IAT, ETCs allowed a clearer detection of anti-RH2 and anti-RH3, but not of anti-RH1 antibodies. Based on our study, it is not clear whether the ETC phase of the gel test should be maintained for RBC antibody screening. J. Clin. Lab. Anal. 21:61,66, 2007. © 2007 Wiley-Liss, Inc. [source] Review of positive direct antiglobulin tests found on cord blood samplingJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 9-10 2005Dorothy Dinesh Until recently, all babies born in Wellington had umbilical cord blood sampling for direct antiglobulin test (DAT). It is considered to be an important test in identifying babies who are at risk of haemolytic disease of the newborn (HDN). Objective: The aim of this review was to examine the utility of positive DAT results and ascertain: , How many cases required phototherapy? , Were any babies readmitted for phototherapy? , Did the positive DAT influence the detection and treatment of HDN? Methods: The clinical records of all newborn babies found to have positive DATs by Wellington Hospital Blood Bank, over a 6-month period (January 2001,June 2001) were reviewed. Blood group serological results of all babies that received phototherapy during this period were also reviewed. Results: Ninety-four babies had a positive DAT, of which 22 (23%) received phototherapy. The incidence of a positive cord blood DAT was found to be 5.5%. In total, 1724 cord blood samples were analysed by Blood Bank over the first 6 months in 2001. Overall 145 babies received phototherapy, 117 were DAT-negative and six were not tested. Six of the 22 (27%) DAT-positive babies that received phototherapy were alerted by a positive DAT, leading to measurement of serum bilirubin (SBR). Twelve of the 22 (55%) were initially alerted by clinical jaundice, leading to measurement of SBR. Two DAT-positive cases were diagnosed antenatally, both were due to anti-D. Overall 10 babies were readmitted for phototherapy, two had a positive DAT. One baby received an exchange transfusion in addition to phototherapy. Two babies that received phototherapy had SBRs in the exchange transfusion range. Eighty-six per cent of the DAT-positive cases treated with phototherapy were due to anti-A. There were four cases of DAT-negative ABO HDN. Conclusions: The positive predictive value of a positive DAT for HDN is 23%. The sensitivity was estimated to be 86%. Ten babies required readmission for phototherapy, two of these were DAT-positive. Jaundice, rather than the positive DAT, was the first alert in the majority of cases of HDN requiring phototherapy. Recommendations for testing are discussed but remain controversial in practice. Assessment for hyperbilirubinaemia in all infants early in life is fundamental. [source] Cut-off value of red-blood-cell-bound IgG for the diagnosis of Coombs-negative autoimmune hemolytic anemia,AMERICAN JOURNAL OF HEMATOLOGY, Issue 2 2009Toyomi Kamesaki Direct antiglobulin test (DAT)-negative autoimmune hemolytic anemia (Coombs-negative AIHA) is characterized by laboratory evidence of in vivo hemolysis, together with a negative DAT performed by conventional tube technique (CTT) in clinically suspected AIHA patients. The immunoradiometric assay (IRMA) for red-blood-cell-bound immunoglobulin G (RBC-IgG) can be used to diagnose patients in whom CTT does not detect low levels of red cell autoantibodies. We investigated the diagnostic cutoff value of the IRMA for RBC-IgG in Coombs-negative AIHA and calculated its sensitivity and specificity. Of the 140 patients with negative DAT by CTT referred to our laboratory with undiagnosed hemolytic anemia, AIHA was clinically diagnosed in 64 patients (Coombs-negative AIHA). The numbers of Coombs-negative AIHA and non-AIHA patients changed with age and gender. The cutoff values were determined from receiver operating characteristic (ROC) curve according to age and gender. The IRMA for RBC-IgG proved to be sensitive (71.4%) and specific (87.8%) when using these cutoffs. Using these cutoffs for 41 patients with negative DAT referred to our laboratory in 2006, all the pseudonegative cases were treated with steroids before the test. The 31 untreated cases could be grouped using one cutoff value of 78.5 and showed 100% sensitivity and 94% specificity, independent of gender and age. Results indicate that RBC-IgG could become a standard approach for the diagnosis of Coombs-negative AIHA, when measured before treatment. Am. J. Hematol., 2009. © 2008 Wiley-Liss, Inc. [source] Does a negative direct antiglobulin test exclude warm autoimmune haemolytic anaemia?BRITISH JOURNAL OF HAEMATOLOGY, Issue 5 2006A prospective study of 504 cases No abstract is available for this article. [source] Maternal IgG anti-A and anti-B titres predict outcome in ABO-incompatibility in the neonateACTA PAEDIATRICA, Issue 12 2009Egil Bakkeheim Abstract Aim:, To evaluate predictors for risk of severe hyperbilirubinaemia and kernicterus in ABO-incompatible neonates with emphasize on maternal IgG anti-A/-B titres. Methods:, Blood group O women in labour at Oslo University Hospital, Ullevål, were included in the years 2004,2006. Offspring with blood group A or B had direct antiglobulin test performed and IgG anti-A/-B levels measured in maternal plasma. Blood group A or B infants developing severe hyperbilirubinaemia, received in addition to phototherapy, immunoglobulin treatment and/or exchange transfusion (EXT). Results:, Of 253 neonates, 61.3% had blood group O, 29.6% blood group A and 9.1% blood group B. Twenty neonates with blood group A or B received at least one immunoglobulin treatment. In multivariate analysis, maternal antibody-titres were the only significant predictors for immunoglobulin treatment (p < 0.0001), EXTs (p < 0.05) and duration of phototherapy (p < 0.0001). The need for invasive treatment increased sharply for antibody titres ,512. Receiver operating characteristic analyses demonstrated that titres ,512 had a sensitivity of 90% and a specificity of 72% for predicting immunoglobulin treatment and thus severe hyperbilirubinaemia. Conclusion:, Maternal IgG anti-A/-B titres contribute to the prediction of risk of severe hyperbilirubinaemia in ABO-incompatible neonates, in addition to blood-grouping and direct antiglobulin-testing, especially following early discharge after delivery. [source] Review of positive direct antiglobulin tests found on cord blood samplingJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 9-10 2005Dorothy Dinesh Until recently, all babies born in Wellington had umbilical cord blood sampling for direct antiglobulin test (DAT). It is considered to be an important test in identifying babies who are at risk of haemolytic disease of the newborn (HDN). Objective: The aim of this review was to examine the utility of positive DAT results and ascertain: , How many cases required phototherapy? , Were any babies readmitted for phototherapy? , Did the positive DAT influence the detection and treatment of HDN? Methods: The clinical records of all newborn babies found to have positive DATs by Wellington Hospital Blood Bank, over a 6-month period (January 2001,June 2001) were reviewed. Blood group serological results of all babies that received phototherapy during this period were also reviewed. Results: Ninety-four babies had a positive DAT, of which 22 (23%) received phototherapy. The incidence of a positive cord blood DAT was found to be 5.5%. In total, 1724 cord blood samples were analysed by Blood Bank over the first 6 months in 2001. Overall 145 babies received phototherapy, 117 were DAT-negative and six were not tested. Six of the 22 (27%) DAT-positive babies that received phototherapy were alerted by a positive DAT, leading to measurement of serum bilirubin (SBR). Twelve of the 22 (55%) were initially alerted by clinical jaundice, leading to measurement of SBR. Two DAT-positive cases were diagnosed antenatally, both were due to anti-D. Overall 10 babies were readmitted for phototherapy, two had a positive DAT. One baby received an exchange transfusion in addition to phototherapy. Two babies that received phototherapy had SBRs in the exchange transfusion range. Eighty-six per cent of the DAT-positive cases treated with phototherapy were due to anti-A. There were four cases of DAT-negative ABO HDN. Conclusions: The positive predictive value of a positive DAT for HDN is 23%. The sensitivity was estimated to be 86%. Ten babies required readmission for phototherapy, two of these were DAT-positive. Jaundice, rather than the positive DAT, was the first alert in the majority of cases of HDN requiring phototherapy. Recommendations for testing are discussed but remain controversial in practice. Assessment for hyperbilirubinaemia in all infants early in life is fundamental. [source] |