Warm Autoimmune Haemolytic Anaemia due to IgA and IgG � A Rare Clinical Scenario

Autoimmune Haemolytic Anaemia (AIHA) is a decompensated acquired haemolysis caused by the host immune system producing autoantibodies that bind to the antigens on the surface of circulating erythrocytes, leading to haemolysis and decreased red cell survival. It requires efficient and advanced immunohaematological and transfusion support. Despite advances in medical field, simple test like Direct Antiglobulin Test (DAT) still remains the diagnostic hallmark. The sensitive column gel technology further helps to characterise these antibodies according to class, subclass and titre of antibodies. It is very important to characterize these autoantibodies as there is a relation between strength of DAT and in vivo haemolysis. Serologically, cases are divided into warm (mainly due to IgG), cold (mainly due to IgM) or mixed depending upon the thermal amplitude of the antibody. IgA and IgG antibodies causing warm type of AIHA are rare as monospecific gel cards are not available in all centres. We here report rare case series of warm AIHA caused by dual antibodies IgA and IgG.

Caracterización fisiopatológica de las anemias hemolíticas autoinmunes / Pathophysiological characterization of autoimmune hemolytic anemia

Introducción: La anemia hemolítica autoinmune se define como el aumento de la destrucción de los eritrocitos en presencia de autoanticuerpos dirigidos contra antígenos de grupos sanguíneos eritrocitarios. Objetivo: Caracterizar las anemias hemolíticas autoinmunes teniendo en cuenta las características fisiopatológicas, manifestaciones clínicas y el diagnóstico de laboratorio. Métodos: Se realizó una revisión de la literatura en inglés y español de artículos publicados en los últimos 10 años sobre anemia hemolítica autoinmune. Conclusiones: La anemia hemolítica autoinmune es una enfermedad muy heterogénea. El diagnóstico suele ser fácil, pero los casos difíciles pueden ser un desafío. La definición de cada tipo es fundamental ya que la terapia es diferente y se enfoca más con la comprensión de los mecanismos patogénicos(AU)

Introduction: Autoimmune hemolytic anemia is defined as increased destruction of red blood cells in the presence of autoantibodies directed against red cell blood group antigens. Objective: To characterize autoimmune hemolytic anemias, taking into account immunohematological, clinical, diagnostic and pathogenic mechanisms. Methods: A review of the literature, in English and Spanish, of articles published in the last 10 years on autoimmune hemolytic anemia was carried out. Conclusions: Autoimmune hemolytic anemia is a very heterogeneous disease. Diagnosis is usually easy, but difficult cases can be challenging. The definition of each type is fundamental since the therapy is different and focuses more on understanding the pathogenic mechanisms(AU)

A case report of hereditary spherocytosis (HS): Approach to diagnosis and management of HS

Hereditary spherocytosis (HS) is a type of congenital hemolytic anemia, in which heterogeneous alterations in one of the six genes that encode for proteins involved in vertical associations which tie the red blood cell (RBC) membrane skeleton to the lipid bilayer causes dysfunction or deficiency of cell membrane protein resulting in spherical-shaped, hyper-dense, and poorly deformable RBCs with a shortened life span. We report a case of HS in a 2-month-old female who presented with severe anemia, jaundice, and hepatosplenomegaly. The peripheral blood smear showed spherocytosis and reticulocytosis. The osmotic fragility was positive and direct antiglobin test was negative. The osmotic fragility test and direct antiglobulin test were positive. She was managed with packed RBCs (PRBCs) transfusion and folic acid supplementation

Anti-Chido/Rodgers antibodies in a patient with infectious disease / Anticuerpos anti-Chido/Rodgers en paciente con enfermedad infecciosa

Introduction: Red cell alloimmunization is an immune response against foreign red cell antigens, usually occurring due to sensibilization in blood transfusions and pregnancies. The Chido (Ch) and Rodgers (Rg) antigens are present in about 96-98 percent of the population in general. Patients who have antibodies against antigens of high frequency in the population are a problem for transfusion medicine. Objectives: To describe the case of a patient diagnosed with AIDS and invasive cancer of the rectum with a recent hospitalization for lower gastrointestinal bleeding and anemia with the presence of anti-Ch and anti-Rg and the difficulties and solutions found for handling the case. Case presentation: Anti-Ch and anti-Rg have not been found to cause a hemolytic transfusion reaction (HTR) or hemolytic disease of the fetus and newborn (HDFN). However, the clinical presentation and laboratory findings including the immunohematological workups concerning the reaction are discussed, with a special emphasis on the benefit of identifying such an antibody and providing a compatible blood unit for transfusion support of the patient. Conclusions: When an antibody against a high-frequency erythrocyte antigen is identified in African or American-descent, anti-Ch or anti-Rg should be considered and that transfusion tests should not be delayed due to its clinical importance(AU)

Introducción: La aloinmunización de glóbulos rojos es una respuesta inmune frente a antígenos de glóbulos rojos extraños, que pueden ocurrir por sensibilización en transfusiones de sangre y embarazos. Los antígenos Chido (Ch) y Rodgers (Rg) están presentes en aproximadamente el 96-98 por ciento de la mayoría de la población. Los pacientes que tienen anticuerpos contra antígenos de alta frecuencia poblacional son un problema para la medicina transfusional. Objetivos: Describir caso de un paciente diagnosticado de AIDS y cáncer invasivo de recto con hospitalización reciente por hemorragia digestiva baja y anemia con presencia de anti-Ch y anti-Rg y las dificultades y soluciones encontradas para el manejo del caso. Presentación de caso: No se ha encontrado que Anti-Ch y anti-Rg causen reacciones hemolíticas transfusionales y enfermedad hemolítica del recién nacido. Sin embargo, se discuten la presentación clínica y los hallazgos de laboratorio, incluidos los estudios inmunohematológicos con respecto a la reacción, con especial énfasis en el beneficio de identificar dicho anticuerpo y obtener una unidad de sangre para transfusión que respalde al paciente con respecto a proporcionar una unidad compatible. Conclusiones: Cuando se identifica anticuerpos contra un antígeno eritrocitario de alta frecuencia, en afrodescendientes o americanos, se deben considerar Anti-Ch o anti-Rg y no retrasar las pruebas de transfusión por su importancia clínica(AU)

Study on the safety of homotype transfusion of military blood donors with negative unexpected antibodies / 中国输血杂志

【Objective】 To analyze the safety of homotypic transfusion in military donors with negative unexpected antibody. 【Methods】 Blood samples (4 mL/person)of eligible military blood donors from November 2018 to October 2019 in our hospital (also working as forces blood station) were conducted for RBC antigen typing, unexpected antibody screening, direct antiglobulin test and cross-match test using microcolumn gel technology, and the compatibility of homotype blood samples was statistical analyzed. 【Results】 A total of 1 577 samples from eligible military blood donors were collected, including A RhD (+ ), B RhD (+ ), O RhD (+ ) and AB RhD (+ ), accounting for 31.39% (495/1 577), 34.37% (542/1 577), 24.10% (380/1 577) and 10.15% (160/1 577), respectively. Six samples presenting positive unexpected antibodies (0.38%, 6/1 577) were screened out, and a total of 7 141 cross-matching tests were performed on 1 571 unexpected antibody negative samples, including A RhD (+ ) [37.36% (2 668/7 141)], B RhD (+ ) [34.81% (2 486/7 141)], O RhD (+ ) [17.71% (1265/7 141)] and AB RhD (+ ) [10.11% (722/7 141)]. There was only 1 case of incompatible cross-matching presented between other donors and clinical patients, and the direct antiglobulin test was 1+ , therefore suspended red blood cells of the donor were scrapped. 【Conclusion】 There was high compatibility and good security of homotype transfusion of military blood donors with negative unexpected antibody.

Influencing factors of RBC products returned by hospitals due to positive DAT, from 2018 to 2020 in Shijiazhuang / 中国输血杂志

【Objective】 To analyze the RBC products returned by hospitals due to positive direct antiglobulin test (DAT), and explore measures to reduce the discarding rate of blood products and ensure the safety of clinical blood use. 【Methods】 The data of RBC products, which were returned by hospitals due to positive-DAT, in Hebei Blood Center from 2018 to 2020 were retrospectively analyzed. The donation time, hospital, gender of blood donors, donation times and DAT typing results were searched through blood donation code, input into the statistical software SPSS17.0, and analyzed by linear trend χ2 and Pearsonχ2. 【Results】 1)The discarding rate of RBC products due to positive DAT in 2018, 2019 and 2020 accounted for 0.15‰, 0.32‰ and 0.26‰, respectively, of the overall RBC collection. The total concordance rate was 89.94% by our retest. 2)The concordance rate of returned blood from secondary hospitals and tertiary hospitals was 78.26% and 91.78%, respectively (P<0.05), with the latter higher than the former. 3)No statistical significance was noticed in the DAT-positive blood by months(P>0.05). 4)The DAT-positive rate of female donors was higher than that of male donors, and that of first-time blood donors was higher than that of repeated and regular blood donors with statistical differences (P<0.05). 5)DAT-positive typing results was mainly due to IgG incomplete antibody. 【Conclusion】 In order to reduce the discarding rate of RBC products, it is suggested to strengthen the consultation before blood collection, encourage healthy males to donate blood and increase the proportion of regular blood donors. Meanwhile, the quality management of Transfusion Department in secondary hospitals should be further improved to ensure the safety of clinical blood transfusion.

Anemia hemolítica autoinmune en paciente pediátrico infectado por virus de inmunodeficiencia humana (VIH); reporte de caso / Autoimmune hemolytic anemia in a pediatric patient infected human immunodeficiency virus (HIV); a case report

Las personas que viven con el virus de inmunodeficiencia humana presentan complicaciones de tipo hematológica durante el curso de la enfermedad, pueden ser propias de su estado mórbido, subyacente a infecciones oportunistas o por el tratamiento antirretroviral. La anemia hemolítica autoinmune constituye una complicación rara y potencialmente letal, en el contexto de la infección por VIH. Presentamos el caso de una lactante mayor de un año nueve meses de edad, con infección perinatal por VIH, diagnosticada con Anemia hemolítica autoinmune por anticuerpos mixtos, con alta reacción inmunológica y mala respuesta al tratamiento clínico. Aunque la prueba de Coombs sigue siendo el estándar oro para el diagnóstico, la positividad de esta no establece el diagnostico per se, pues puede ser positiva entre el 18-43% de los pacientes infectados por VIH.

People living with human immunodeficiency virus present hematological complications during course of disease, they may be due to their morbid state, underlying opportunistic infections or due to antirretroviral treatment. Autoimmune hemolytic anemia is a rare and potentially fatal complication of HIV infection. We present case of an infant older than one year nine months, for perinatal HIV infection, diagnosed with autoimmune hemolytic anemia due to mixed antibodies, with high immunological reaction and poor response to clinical treatment. Although the Coombs test remains the gold standard for diagnosis, its positivity does not establish the diagnosis per se, it can positive in 18-43% of HIV-infected patients.

Effect of blood component transfusion in patients with negative to positive results of direct antiglobulin test after blood transfusion / 中国输血杂志

【Objective】 To analyze the effect of blood component transfusion when the results of direct antiglobulin test (DAT) changed from negative to positive after blood transfusion. 【Methods】 The data of 215 surgical blood recipients, who were admitted in our hospital from January to October 2019 and presented negative results for both DAT and irregular antibody screening (Anti-screening), were collected via Ruimei Laboratory Management System. DAT and Anti-screening were performed again after blood transfusion, and DAT positive patients(re-test positive group) were then subject to antibody classification and polybrene cross-matching (referred to as cross-matching), and Anti-screening positive patients were tested for irregular antibodies. Patients were stratified by perioperative RBCs transfusion volume as ≤4 U (150 ± 10% mL/U), >4 to 8 U and > 8 U, and DAT-negative patients after blood transfusion were set as the controls, and the transfusion effect of DAT-positive patients after blood transfusion was compared with them. 【Results】 8.84% (19/215) of DAT-negative patients turned positive after RBCs transfusion, among which IgG type accounted for 84.21% (16/19) and IgG+ C3 15.79% ( 3/19); two patients(anti-E and-M, 10.53%) were positive in anti-screening re-test and the rest were negative (89.47%, 17/19). As for cross matching, incompatibility of both primary and secondary side, primary side and secondary side accounted for 5.26% (1/19), 5.26% (1/19) and 10.52 (2/19), respectively, while 78.95% (15/19) showed compatibility of both primary and secondary side. The Hb, RBC and Hct values of the re-test positive group, received RBC transfusion volume (U)≤4 and >4~8, were effectively elevated compared with the controls (P8 U(P>0.05). 【Conclusion】 The conversion of DAT negative results to positive after RBC transfusion indicates the patient has developed antibodies or the incidence of blood transfusion reaction, which can provide references for the clinical choice of appropriate blood components to ensure the safety and effectiveness of blood transfusion.

Evaluation of modified IAT with twoself-made low ionic-strength solutions / 中国输血杂志

【Objective】 To explore the clinical applications of low ionic strength salt solution polyethylene glycol (LISS-PEG) and low ionic strength salt solution bovine serum albumin (LISS-BSA) in the indirect antiglobulin test (IAT). 【Methods】 The common standard red blood cell(RBC) IgG irregular antibodies (anti-D, anti-M, anti-N, anti-S, anti-s, anti-Jka, anti-Jkb, anti-Fya, anti-Fyb, anti-Dia, anti-K) were reacted with RBCs with corresponding antigens in IAT with LISS-PEG and LISS-BSA modification for 5-minute and 10-minute incubations, and then compared the results with conventional IAT. One hundred of blood samples from patients presenting irregular antibodies of erythrocyte IgG were selected to observe the effect of these two self-made modification. The agglutination intensity was recorded by AABB scoring method. 【Results】 No difference was noticed in IAT intensity reaction between LISS-PEG 5-minute and 15-minute incubation (P>0.05), nor between 5-minute/15-minute LISS-BSA incubation and conventional IAT (P>0.05). However, LISS-PEG modification demonstrated a significant superiority over the conventional technique just after incubation with 5 minutes(P<0.05). 【Conclusion】 Using the self-made LISS-PEG as the enhancement medium allows not only reduced incubation time (5 minutes) but also increased intensity of the reaction, which shortens the cross-matching time for emergency blood transfusion and is worthy of popularization.

Transfusion management for patients taking an anti-CD38 monoclonal antibody

Abstract Introduction: Pre-transfusion tests, essential for the release of blood components, may be affected by drugs. Monoclonal antibodies represent a class of medications increasingly used in the clinical practice, with anti-CD38 monoclonal antibodies (daratumumab) being a promising resource in the treatment of refractory myeloma. This monoclonal antibody recognizes CD38 in myeloma cells and interferes with pre-transfusion tests by causing panreactivity in indirect antiglobulin tests thereby clinically masking alloantibodies. Dithiothreitol is a reagent that breaks disulfide bonds and effectively destroys antigenic sites for CD38 on red blood cells. This study reports the immunohematological findings of pre-transfusion tests of patients with multiple myeloma receiving daratumumab and on solutions to prevent the interference of this monoclonal antibody. Methods: Serum samples from five patients on anti-CD38 monoclonal antibody treatment were evaluated. Tests performed included ABO/RhD typing, indirect antiglobulin test, direct antiglobulin test and eluate test. A daily evaluation was performed to determine the shelf life of dithiothreitol-treated red blood cells when stored in Alsever's solution. Results: No interference in the ABO/RhD typing results was noted but in all samples, a panreactivity was observed in indirect antiglobulin tests. Regarding the direct antiglobulin test, two samples presented positive results but negative eluates. In all samples, treatment of reagent red blood cells with 0.2 M dithiothreitol offset interference by anti-CD38 monoclonal antibodies. Dithiothreitol-treated red blood cells stored in Alsever's solution were stable for up to 15 days. Conclusion: Treatment of reagent red blood cells with dithiothreitol can be efficient and accessible to offset the interference of the anti-CD38 drug in pre-transfusion tests. The number of costly serological workups can be reduced by having stored dithiothreitol red blood cells with this proving to be a useful reagent for investigating anti-CD38.

Warm autoimmune hemolytic anemia: experience from a single referral center in Mexico City

BACKGROUND: Autoimmune hemolytic anemia (AIHA) is characterized by an autoimmune-mediated destruction of red blood cells. Warm AIHA (wAIHA) represents 60% of AIHA cases and is associated with the positive detection of IgG and C3d in the direct antiglobulin test (DAT). This study aimed to assess the clinical and laboratorial differences between primary and secondary wAIHA patients from a referral center in Mexico City. METHODS: All patients diagnosed with wAIHA in our institution from January 1992 to December 2015 were included and received corticosteroids as the first-line treatment. We analyzed the response to the first-line treatment, relapse-free survival, and time to splenectomy. RESULTS: Eighty-nine patients were included. Secondary wAIHA represented 55.1% of the cases. At diagnosis, secondary wAIHA patients showed a DAT mixed pattern more frequently than primary wAIHA patients (36.7 vs. 17.5%, P<0.001). In the survival analysis, patients with secondary wAIHA had a lower time to response (18 vs. 37 days, P=0.05), median disease-free survival (28.51 vs. 50.95 weeks, P=0.018), and time to splenectomy (43.5 vs. 61 wks, P=0.029) than those with primary wAIHA. Due to economic constraints, rituximab was considered as the third-line treatment in only two patients. CONCLUSION: Secondary wAIHA may benefit from a longer low-dose steroid maintenance period mainly due to its shorter time to relapse and time to splenectomy than primary wAIHA.

The Clinical Significance of Implementing Concurrent Direct Antiglobulin Test and Antibody Elution Test in Diagnosing Hemolytic Disease of the Fetus and Newborn / 대한수혈학회지

BACKGROUND: Hemolytic disease of the fetus and newborn (HDFN) is a condition in which immune hemolytic anemia occurs in fetuses or newborns as a result of maternal alloimunized antibodies transfer. Antibody elution test and direct antiglobulin test (DAT) can be performed to diagnose HDFN; maternal originated antibodies cannot be confirmed if DAT is utilized alone. In this study, we analyzed the clinical significance of implementing concurrent DAT and antibody elution test in diagnosing HDFN. METHODS: We retrospectively analyzed the DATs and antibody elution tests that were simultaneously conducted in a period of 11 years, between 2005 and 2015, in newborns that received hemoglobin, reticulocyte, and total bilirubin tests. According to the results of these tests, the number of newborns diagnosed with HDFN was measured. Furthermore, the sensitivity and specificity of DAT and antibody elution test were compared. RESULTS: Among 325 newborns, the results of DATs and antibody elution tests were both negative in 208 (64.0%), negative and positive, respectively, in 80 (24.6%), positive and negative in 10 (3.1%), both positive in 27 (8.3%). When this was compared to the clinical diagnosis of HDFN, more sensitive and specific diagnoses were possible when implementing DAT and antibody elution test together (sensitivity of 76.9% for antibody elution test and specificity of 90.3% for DAT). Twenty-six (8.0%) newborns suspected for HDFN showed clinically significant hemolytic anemia. CONCLUSION: It is necessary to conduct both DAT and antibody elution test when HDFN is suspected. The severity of hemolysis in HDFN can be indirectly anticipated using an antibody elution test confirming maternal originated alloantibodies.

Application of microcolumn gel technology in detection of neonatal hemolytic disease / 国际检验医学杂志

Objective To investigate the application value of microcolumn gel technology in screening hemolytic disease of the newborns(HDN) .Methods The direct antiglobulin test(DAT) ,antibody release test and free antibody test were performed in 212 cases of suspected HDN in our hospital by using microcolumn gel assay .Results In 212 cases of suspected HDN ,50 cases(23 .6% ) were diagnosed as HDN ,including 45 cases (21 .2% ) of ABO‐HDN and 5 cases (2 .4% ) of Rh‐HDN .In 45 cases of ABO‐HDN ,23 cases (36 .5% ) were A blood type and 22 cases (28 .2% ) were B blood type .The sensitivity of antibody release test ,DAT and free antibody test was 100% ,28% and 92% respectively .Conclusion The microcolumn gel technology can detect HDN fastly and accu‐rately ,with the advantages of simple operation ,less sample consumption ,high sensitivity and specificity ,which can provide reliable basis for HDN diagnosis and is worth popularizing and applying in clinic .

Analysis of test results of ABO hemolytic disease of newborn in Chizhou area / 国际检验医学杂志

Objective To understand the laboratory testing current situation of ABO hemolytic disease of the newborn(ABO-HDN)in Chizhou area,and to analyze the test results of serological three indexes tests in order to provide the basis for clinical diag-nosis.Methods The ABO blood group identification and serological three indexes tests(direct antiglobulin test,free antibody test, antibody release test)were performed by using microcolumn gel method.Results A,B,O and AB blood groups were 29.13%, 31.09%,37.82% and 1.96%;the total positive rate of ABO-HDN was 22.41%(80/357),the positive rates of ABO-HDN in A and B blood groups were 38.46% (40/104)and 36.04% (40/111 )respectively;the occurrence rate of ABO-HDN had no statistical difference between blood group A and B (P >0.05);the positive rates of the direct antiglobulin test,free antibody test and antibody release test were 1.96%(7/357),4.76%(17/357)and 22.41%(80/357)respectively.Conclusion The serological three indexes tests are the main basis for the diagnosis of ABO-HDN,the antibody release test shows the highest positive rate.If clinically consid-ering HDN,the newborns should conduct the ABO-HDN screening as early as possible for clarifying the diagnosis and performing the early treatment.

Exploration of Appropriate Cross-Matching Methods for Positive Patients of the Direct Antiglobulin Test / 现代检验医学杂志

Objective To investigate the appropriate cross-matching methods for the direct antiglobulin test (DAT)positive patients.Methods The DAT was used to screen the irregular antibodies on the surface of erythrocytes.The microcolumn gel test was used for blood identification.The antiglobulin test and manual polybrene test were used for cross-matching.Re-sults A total of five DAT positive cases were collected in study.The blood groups of each case were detected,including A-DCcEe,O-DCCee,O-DCcee,A-DCCee and A-DCcee.The donor samples with corresponding blood-antigen negative were cho-sen for cross-matching,and the agglutination intensity of each cross-matching tube was weaker than the control.The transfu-sion of washed red blood cells was suggested.Finally,each transfusion was safe and efficient.Conclusion The infusion of the washed red blood cells with corresponding blood-antigen negative could efficiently ensure the safety of blood transfusion.

Investigation on blood group serology of crossmatching incompatibility of blood donors in clinical hospitals / 国际检验医学杂志

Objective To investigate on blood group serology of crossmatching incompatibility of blood donors in clinical hospi‐tals in Nanchong from 2010 to 2014 .Methods According to blood group serological test ,direct antiglobulin test (DAT ) was used for blood specimen with crossmatching incompatibility where donor was suspected as the causes ,at the same time irregular antibody was screened and identified .Results Among 77 returned blood specimens ,positive DAT were found in 43 cases ;while irregular an‐tibodies were found in 18 cases ,with anti‐M and anti‐E as the major ,followed by anti‐Lea and anti‐P1;and 16 cases did not find ab‐normality .Conclusion Causes of crossmatching incompatibility of blood donors in clinical hospitals in Nanchong are mastered through the survey ,to improve the safety level of clinical blood transfusion and avoid the waste of the blood .

Analysis of serological test results of neonatal hemolytic disease and related factors in neonatal hyperbilirubinemia / 国际检验医学杂志

Objective To analyze the serological detection results of hemolytic disease of newborns(HDN)in neonatal hyperbil-irubinemia and to explore the relationship between serological results and related factors.Methods The neonatal hemolytic three i-tems test were performed on blood specimens of 796 cases of neonatal hyperbilirubinemia.The relationship between the positive rate of HDN with the related factors such as blood type,specimens collecting time,hemoglobin level and serum total bilirubin value was analyzed.Results Among 796 cases of hyperbilirubinemia,184 cases were HDN(23.12%),in which 796 cases were ABO-HDN and 8 cases were Rh-HDN.The direct free antibody test,antibody release test and direct antiglobulin test were positive in 180 cases (22.61%),184 cases(23.12%)and 140 cases(17.59%)respectively.The HDN positive rate of the newborns with B blood type was higher than that of the newborns with A blood type,the difference between them had statistical significance(χ2 = 10.304,P <0.05).The HDN positive rate was closely related with the specimen collection time,moreover,the greater the day age,the higher the HDN positive rate,the difference showing statistical significance(P <0.05).The hemoglobin level and serum total bilirubin val-ue had statistically significant difference between newborns with HDN and those without HDN(P <0.05).Conclusion The posi-tive rate of HDN is high in newborns with hyperbilirubinemia.The hemolytic three items test should be performed as early as possi-ble.Combining with the hemoglobin level and serum total bilirubin value can increase the HDN detection rate.

Annual Report on External Quality Assessment in Blood Bank Tests in Korea (2009) / 임상검사와정도관리

BACKGROUND: We report here the results of surveys for external quality assessment of blood bank tests performed in 2009. METHODS: Survey specimens were sent three times to 488, 491 and 490 participant institutes, and the response rates for the 1st, 2nd and 3rd trial were 97.7%, 98.0%, and 98.0%, respectively. Test items for the surveys were ABO grouping, Rh (D) typing, crossmatching, direct antiglobulin test, antibody screening and antibody identification test. RESULTS: The average accuracy rates of ABO grouping and Rh typing were 99.6-100% and 98.5-100%, respectively. In crossmatching test, the accuracy rates were 99.3-99.8% for the compatible samples, 92.7-100% for the incompatible samples, and 92.6-93.1% for the samples which could be detected as incompatible only by antiglobulin method. The accuracy rates of direct antiglobulin test were 98.5-100% for negative samples and 98.1-98.8% for positive samples. The correctresults were reported by 98.0-100% of the surveyed institutions for antibody screening test and 82.9-100% for antibody identification test. Nineteen institutions gave repeatedly incorrect answers for crossmatching test. Eight institutions out of them gave incorrect answers for all the test specimens sent out 3 times last year. CONCLUSIONS: The overall results of this survey were good, however, it is required that the institutions where the incorrect results were reported should perform corrective actions for quality improvement.

Caracterización de pacientes adultos con anemia hemolítica autoinmune atendidos en el Instituto de Hematología e Inmunología / Characterization of adult patients presenting with autoimmune hemolytic anemia seen in Hematology and Immunology Institute

Las anemias hemolíticas autoinmunes (AHAI) se caracterizan por la destrucción, mediada por autoanticuerpos, de los eritrocitos del paciente. Los autoanticuerpos causantes del proceso hemolítico se clasifican en calientes y fríos en dependencia de la temperatura óptima de su reacción in vitro. Esta enfermedad se asocia frecuentemente con otras enfermedades autoinmunes, con las hemopatías malignas y con el tratamiento con determinados fármacos. En el Instituto de Hematología e Inmunología se atienden actualmente en consulta externa 35 pacientes adultos con AHAI, con un rango de edad entre 18 y 60 años, 65,7 % del sexo femenino y 94 % de la raza blanca. Treinta y tres de los casos (94,2 %) presentan AHAI por anticuerpos calientes y 2 (5,7 %) un síndrome de aglutininas frías. La prueba de antiglobulina directa (PAD) en el momento del diagnóstico fue positiva en 32 pacientes (91,43 %) y mostró los patrones: IgG+C3d (62,50 %), IgG (18,75 %), C3d (16,62 %) e IgA (3,12 %). En 3 pacientes (8,57 %) la PAD fue negativa. De acuerdo con la etiología, 30 son idiopáticas y 5 secundarias a otras enfermedades. El 68, 5 % de los pacientes respondió satisfactoriamente al tratamiento con esteroides y los restantes requirieron tratamiento con otros inmunosupresores (azatioprina, ciclofosfamida) o esplenectomía. Actualmente, 17 se mantienen sin tratamiento.

The autoimmune hemolytic anemias (AIHA) are characterized by the destruction of auto-antibodies-mediated patient's erythrocytes. The autoantibodies causing the hemolytic process are classified in hot and cold depending of the optimal temperature of its in vitro reaction. This disease is frequently associated with other autoimmune diseases, with malignant blood diseases, and with the treatment using specific drugs. At the present times, in the external consultation of the Hematology and Immunology Institute are seen 35 adult patients presenting with AIHA, with an age rank between 18 and 60 years, the 65,7% is female sex and the 94% of white race. Thirty three of the cases (94,2%) has AIHA by hot antibodies and 2 (5,7%) with a cold agglutinins syndrome. The direct antiglobulin test (DAT) at diagnosis was positive in 32 patients (91,43%) and showed the following patterns: IgG+C3d (62,50%), IgG (18,75%), C3d (16,62%) and IgA (3,12%). In three patients (8.75%) the DAT was negative. According to etiology, 30 are idiopathic and 5 secondary to other diseases. The 68,5% of patients respond adequately to treatment with steroids and remainder, required treatment with other immunosuppressive agents (azathioprine, cyclophosphamide) or splenectomy. At present time, 17 have not treatment.

Utilidad de la prueba directa de Coombs en el tamiz neonatal / Usefulness of direct antiglobulin test in neonatal screening

Introducción. La ictericia es un evento clínico frecuente que se presenta en los recién nacidos; las causas más frecuentes involucradas en la enfermedad hemolítica del recién nacido (EHRN) continúan siendo la incompatibilidad al sistema ABO y la isoinmunización a RhD. La prueba directa de Coombs (PDC) permite identificar la presencia de anticuerpos antieritrocitarios del isotipo IgG, provenientes del suero materno en la superficie de los eritrocitos del feto o neonato. Objetivo: presentar los resultados y especificidad de la prueba directa de Coombs (PDC) como prueba en el tamiz neonatal. Métodos. Consecutivamente se incluyeron a recién nacidos no seleccionados. En las primeras horas de vida se determinó el grupo sanguíneo ABO/RhD y la PDC con suero poliespecífico y monoespecíficos (anti-IgG y C3b/C3d). Resultados. Se incluyeron 5 007 recién nacidos, la PDC positiva se documentó en 181 neonatos (3.6%). Los casos del grupo sanguíneo A, B o AB, mostraron mayor riesgo de tener PDC positiva que los del grupo O (razón de momios 2.3, intervalo de confianza 95% 1.7-3.1). La PDC positiva se presentó en 3.5% de los neonatos RhD positivo y en 1.9% de los RhD negativo; 72.9% de los neonatos con PDC positiva tuvieron titulaciones de 1:2, 1 ;4 y 1:8, con el 33.1, 19.9 y 19.9%, respectivamente. En los neonatos con PDC positiva se pudo establecer el isotipo anti-IgG en 117 casos (64.6%), complemento sólo en 6 casos (3.3%), la combinación de ambas en 6 casos (3.3%) y en 52 neonatos (28.8%), con PDC poliespecífico positivo, no se pudo identificar la especificidad de la reacción. Conclusión. La prevalencia elevada (3.6 %) de PDC positiva en la detección neonatal rutinaria, apoya la indicación de incorporar dicha prueba al tamiz neonatal, independientemente del grupo ABO y Rh materno. Queda por establecer su beneficio en la detección temprana de la ictericia neonatal.

Background. Neonatal jaundice is a clinical event frequently present in newborns. The causes most frequently involved in hemolytic disease of newborn (HDN) are still the incompatibilities to the ABO/Rh blood system. Direct Coombs test (or direct antiglobulin test, DAT) allows identification of the presence of red blood cell antibodies (IgG isotype) coming from the maternal serum on the surface of the fetus erythrocytes. The purpose of this study is to show the results and specificity of DAT as screening in newborn infants. Methods. We studied unselected neonates in a cross-sectional design. During the early hours of life, we determined ABO/Rh and DAT with poly- and monospecific reagents (anti-IgG and C3b/C3d). Results. We included 5 007 newborns; 181 cases (3.6%) were DAT positive. Newborns with A, B or AB blood groups showed an increased association of being DAT positive than group O (OR 2.3, 95% Cl 1.7-3.1). DAT was positive in 3.5% of RhD-positive infants and 1.9% of RhD-negative infants. In six DAT-positive cases, 117 cases (64.6%) had anti-IgG bound to red cell membrane, complement in six cases (3.3%), and 52 newborns (28.8%) were polyspecific DAT positive and monospecific DAT negative. Conclusions. The high prevalence (3.6%) of DAT-positive cases in routine neonatal detection supports the indication to incorporate DAT into neonatal screening, regardless of the mother's blood group. The benefit of early intervention in neonatal jaundice remains to be established.