Meaning of leprosy for people who have experienced treatment during the sulfonic and multidrug therapy periods / Significado da hanseníase para pessoas que viveram o tratamento no período sulfônico e da poliquimioterapia / Significado de la lepra para personas que experimentaron el tratamiento en el período sulfónico y de poliquimioterapia

AbstractObjective: to analyze the meanings of leprosy for people treated during the sulfonic and multidrug therapy periods.Method: qualitative nature study based on the Vigotski's historical-cultural approach, which guided the production and analysis of data. It included eight respondents who have had leprosy and were submitted to sulfonic and multidrug therapy treatments. The participants are also members of the Movement for Reintegration of People Affected by Leprosy.Results: the meanings were organized into three meaning cores: spots on the body: something is out of order; leprosy or hanseniasis? and leprosy from the inclusion in the Movement for Reintegration of People Affected by Leprosy.Conclusion: the meanings of leprosy for people submitted to both regimens point to a complex construction thereof, indicating differences and similarities in both treatments. Health professionals may contribute to the change of the meanings, since these are socially constructed and the changes are continuous.

ResumoObjetivo:analisar significados da hanseníase para as pessoas que foram tratadas no período sulfônico e no período da poliquimioterapia.Método:estudo de natureza qualitativa fundamentado na abordagem histórico-cultural de Vigotski, a qual orientou a construção e análise dos dados. Foram incluídos oito entrevistados que já tiveram hanseníase e que realizaram tratamento no período sulfônico e da poliquimioterapia, sendo participantes do Movimento de Reintegração das Pessoas Atingidas pela Hanseníase.Resultados:os significados foram organizados em três núcleos de significação: manchas no corpo: alguma coisa está fora de ordem; lepra ou hanseníase? e hanseníase a partir da inserção no Movimento de Reintegração das Pessoas Atingidas pela Hanseníase.Conclusão:os significados de hanseníase para pessoas tratadas nos dois períodos apontam para a construção complexa dos mesmos, indicando diferenças e semelhanças nos dois períodos. Os profissionais de saúde podem contribuir para a mudança de significados, pois esses são socialmente construídos e as transformações são contínuas.

ResumenObjetivo:analizar los significados de la lepra para las personas que fueron tratadas en el período sulfónico y en el período de poliquimioterapia.Método:estudio de naturaleza cualitativa fundamentado en el abordaje histórico cultural de Vygotsky, el cual orientó la construcción y análisis de los datos. Fueron incluidos ocho entrevistados que ya tuvieron lepra y que realizaron tratamiento en el período sulfónico y de poliquimioterapia, siendo participantes del Movimiento de Reintegración de Personas Afectadas por la Lepra.Resultados:los significados fueron organizados en tres núcleos de significación: manchas en el cuerpo: alguna cosa está fuera de orden; ¿Lepra o enfermedad de Hansen?; y lepra a partir de la inserción en el Movimiento de Reintegración de Personas Afectadas por la Lepra. Conclusión: los significados de la lepra para las personas tratadas en los dos períodos apuntan para la construcción compleja de los mismos, indicando diferencias y semejanzas en los dos períodos. Los profesionales de la salud pueden contribuir para el cambio de significados, ya que estos son socialmente construidos y las transformaciones son continuas.

Interlaboratory Comparison of the Results of Lifecodes LSA Class I and Class II Single Antigen Kits for Human Leukocyte Antigen Antibody Detection

BACKGROUND: Although single antigen bead assays (SAB) are approved qualitative tests, the median fluorescence intensity (MFI) values obtained from SAB are frequently used in combination with quantitative significances for diagnostic purposes. To gauge the reproducibility of SAB results, we assessed the interlaboratory variability of MFI values using identical kits with reagents from the same lot and the manufacturer's protocol. METHODS: Six serum samples containing HLA-specific antibodies were analyzed at five laboratories by using Lifecodes LSA Class I and Class II SAB kits (Immucor, USA) from the same lot, according to the manufacturer's protocol. We analyzed the concordance of qualitative results according to distinct MFI cutoffs (1,000, 3,000, 5,000, and 10,000), and the correlation of quantitative MFI values obtained by the participating laboratories. The CV for MFI values were analyzed and grouped by mean MFI values from the five laboratories ( or =10,000). RESULTS: The categorical results obtained from the five laboratories exhibited concordance rates of 96.0% and 97.2% for detection of HLA class I and class II antibodies, respectively. The Pearson correlation coefficients for MFI values of class I and class II antibodies were between 0.947-0.991 and 0.992-0.997, respectively. The median CVs for the MFI values among five laboratories in the lower MFI range (<1,000) were significantly higher than those for the other MFI ranges (all P<0.01). CONCLUSIONS: Analysis of SAB performed in five laboratories using identical protocols and reagents from the same lot resulted in high levels of concordance and strong correlation of results.

Duffy Blood Group Genotyping in Thai Blood Donors

BACKGROUND: Duffy (FY) blood group genotyping is important in transfusion medicine because Duffy alloantibodies are associated with delayed hemolytic transfusion reactions and hemolytic disease of the fetus and newborn. In this study, FY allele frequencies in Thai blood donors were determined by in-house PCR with sequence-specific primers (PCR-SSP), and the probability of obtaining compatible blood for alloimmunized patients was assessed. METHODS: Five hundred blood samples from Thai blood donors of the National Blood Centre, Thai Red Cross Society, were included. Only 200 samples were tested with anti-Fy(a) and anti-Fy(b) using the gel technique. All 500 samples and four samples from a Guinea family with the Fy(a-b-) phenotype were genotyped by using PCR-SSP. Additionally, the probability of obtaining antigen-negative red blood cells (RBCs) for alloimmunized patients was calculated according to the estimated FY allele frequencies. RESULTS: The FY phenotyping and genotyping results were in 100% concordance. The allele frequencies of FY*A and FY*B in 500 central Thais were 0.962 (962/1,000) and 0.038 (38/1,000), respectively. Although the Fy(a-b-) phenotype was not observed in this study, FY*B(ES)/FY*B(ES) was identified by PCR-SSP in the Guinea family and was confirmed by DNA sequencing. CONCLUSIONS: Our results confirm the high frequency of the FY*A allele in the Thai population, similar to that of Asian populations. At least 500 Thai blood donors are needed to obtain two units of antigen-negative RBCs for the Fy(a-b+) phenotype.

Molecular matching of red blood cells is superior to serological matching in sickle cell disease patients

OBJECTIVE: To evaluate the usefulness of DNA methods to provide a means to precisely genotypically match donor blood units for the antigen-negative type of 35 sickle cell disease patients<. METHODS: Red blood cell units were investigated for ABO, D, C, c, E, e, K, Fyª, Fy b, Jkª, Jk b, S, s, Diª and RH variants by performing a molecular array (Human Erythrocyte Antigen BeadChipTM, BioArray Solutions), polymerase chain reaction followed by restriction fragment length polymorphism analysis and sequencing of patient samples and donor units that had been serologically matched based on the ABO, Rh and K phenotypes and the presence of antibodies. RESULTS: Matches for 21 of 35 sickle cell disease patients presented discrepancies or mismatches for multiple antigens between the genotype profile and the antigen profile of their serologically-matched blood units. The main discrepancies or mismatches occurred in the RH, FY, JK and MNS systems. Eight Rh alloimmunized patients presented RHD and RHCE variants that had not been serologically identified. According to these results better matches were found for the patients with genotyped units and the patients benefited as shown by better in vivo red blood cell survival. CONCLUSION: Molecular matching is superior to serological matching in sickle cell disease patients, decreasing the risk of transfusion reactions, especially delayed transfusion reactions to existing alloantibodies and preventing alloimmunization.

Study of possible clinical and laboratory predictors of alloimmunization against red blood cell antigens in cancer patients

Background: The inflammatory background of patients influences the process of alloimmunization against red blood cell antigens. Proof of this statement to clinical practice is still lacking. Objective: The aim of this study was to verify whether factors related to disease severity and inflammatory status of cancer patients can predict alloimmunization. Methods: This was a case-control study in which alloimmunized oncologic patients treated between 2009 and 2012 were compared with a non-alloimmunized control group regarding the severity of the disease (metastasis/performance status/body mass index) and C-reactive protein levels. Results: The groups did not differ significantly in terms of C-reactive protein, Eastern Cooperative Oncology Group (ECOG)/Karnofsky performance status, presence of metastasis and body mass index. Conclusion: It is not possible to predict alloimmunization in cancer patients based on severity of illness and inflammatory markers. Strategies of screening patients by phenotyping blood based on these criteria are not justified. .

A Multicenter Retrospective Analysis of the Clinical Features of Pernicious Anemia in a Korean Population

To determine the approximate incidence and clinical features of pernicious anemia in a Korean population, we retrospectively analyzed clinical data for patients with pernicious anemia who were diagnosed between 1995 and 2010 at five hospitals in Chungnam province. Ninety-seven patients were enrolled, who accounted for 24% of patients with vitamin B12 deficiency anemia. The approximate annual incidence of pernicious anemia was 0.3 per 100,000. The median age was 66 (range, 32-98) yr, and the male/female ratio was 1.25. Anemia-associated discomfort was the most common symptom (79.4%), followed by gastrointestinal and neurological symptoms (78.4% and 38.1%, respectively). Pancytopenia was found in 36 patients (37.1%), and autoimmune disorders were found in 15 patients (15.5%). Antibody to intrinsic factor was detected in 62 (77.5%) of 80 patients examined, and antibody to parietal cells was detected in 35 (43.2%) of 81 patients examined. Of the 34 patients who underwent tests for Helicobacter pylori, 7 (12.5%) were positive. The anemia-associated and gastrointestinal symptoms resolved completely in all patients after intramuscular injection of cobalamin, whereas neurological symptoms remained in some. In conclusion, pernicious anemia is less frequent in Koreans than in Western populations; however, the clinical features of this disorder in Koreans do not differ from those of Western cases.

Autoantibodies with Mimicking Specificity Detected by the Dilution Technique in Patients with Warm Autoantibodies

BACKGROUND: The aim of this study was to investigate the frequency of autoantibodies with mimicking specificity by using the dilution technique, to assess the usefulness of the combination of the dilution technique and red blood cell (RBC) phenotyping, and to establish a pre-transfusion testing algorithm in patients with warm autoantibodies. METHODS: Serum samples from 71 patients with warm autoantibodies were tested using the dilution technique. Among them, 25 samples were adsorbed with allogeneic ZZAP (a combination of dithiothreitol and enzyme) or polyethylene glycol (PEG) and their RBC phenotypes were determined. Thirty-nine patients were transfused with our pre-transfusion testing algorithm using a combination of dilution technique and RBC phenotyping. RESULTS: Autoantibodies with mimicking specificity were detected by the dilution technique in 26.8% (19/71) of the patients and most of them were directed against Rh system antigens. The agreement of the results obtained with the dilution technique in combination with RBC phenotyping and those from ZZAP or PEG adsorption was 100% (18/18) in patients who have autoantibodies with mimicking specificity and/or alloantibodies. No clinical symptoms indicating severe acute or delayed hemolytic transfusion reactions were reported in the 39 patients transfused with our pre-transfusion testing algorithm. CONCLUSIONS: Autoantibodies with mimicking specificity detected by the dilution technique in patients with warm autoantibodies are relatively frequent, can be discriminated from alloantibodies by employing a combination of dilution technique and RBC phenotyping, and might not appear to cause severe acute or delayed hemolytic transfusion reactions.

Application of Calculated Panel Reactive Antibody Using HLA Frequencies in Koreans

BACKGROUND: Introduction of the Luminex panel reactive antibody (PRA)-single antigen (SA) assay has increased the detection rates of unacceptable antigens in sensitized patients; the calculated PRA (CPRA) level represents the percentage of actual organ donors that express 1 or more of these unacceptable antigens. We developed a CPRA calculator based on the HLA frequencies in Koreans to measure sensitization levels in Korean patients. METHODS: To develop the calculator, we obtained the HLA-A, HLA-B, and HLA-DR phenotypes of 1,622 Koreans, and compared these with previously reported frequencies in Koreans. Sera from patients awaiting kidney transplantation were tested for HLA antibodies by Luminex PRA-screen, PRA-identification (ID), and PRA-SA assays. The measured %PRA from the PRA-screen (N=55) and PRA-ID (N=71) were compared to the %CPRA for the unacceptable antigens obtained from PRA-SA. RESULTS: Phenotype frequencies used for the CPRA calculator agreed with previously reported data. The concordance rates among the 3 PRA methods for the detection of class I and class II antibodies were 76.1-81.8% (kappa, 0.519-0.636) and 72.7-83.6% (0.463-0.650), respectively. For the detection of broadly sensitized sera (>50% or >80%), the concordance rates were over 80%. In sera with 80-100% CPRA, 91.7% and 94.4% of the samples had concordant results (80-100% PRA) in the PRA-screen and PRA-ID assay, respectively. CONCLUSIONS: Although further clinical studies are required to confirm the benefits of CPRA values, adoption of CPRA analysis based on HLA frequencies in Koreans may be useful for sensitization measurements and organ-allocation algorithms.

Two Cases of Transfusion-related Acute Lung Injury Triggered by HLA and Anti-HLA Antibody Reaction

Transfusion-related acute lung injury (TRALI) is a serious adverse transfusion reaction that is presented as acute hypoxemia and non-cardiogenic pulmonary edema, which develops during or within 6 hr of transfusion. Major pathogenesis of TRALI is known to be related with anti-HLA class I, anti-HLA class II, or anti-HNA in donor's plasma. However, anti-HLA or anti-HNA in recipient against transfused donor's leukocyte antigens also cause TRALI in minor pathogenesis and which comprises about 10% of TRALI. Published reports of TRALI are relatively rare in Korea. In our cases, both patients presented with dyspnea and hypoxemia during transfusion of packed red blood cells and showed findings of bilateral pulmonary infiltrations at chest radiography. Findings of patients' anti-HLA antibodies and recipients' HLA concordance indicate that minor pathogenesis may be not as infrequent as we'd expected before. In addition, second case showed that anti-HLA class II antibodies could be responsible for immunopathogenic mechanisms, alone.

Desensibilización y trasplante renal: plasmaféresis-IVIG a dosis estándar en pacientes con alto riesgo inmunológico / Desensitization and renal transplant: plasmapheresis/IVIG standard dose in patients with high immunological risk

Introducción: Los pacientes con alto riesgo inmunológico siguen siendo relegados a la cada vez más larga lista de espera de un donador inmunológicamente compatible. El objetivo de esta comunicación es informar la experiencia de un centro de trasplantes en la desensibilización de pacientes con alto riesgo inmunológico. Material y métodos: Estudio descriptivo y retrospectivo de todos los pacientes sometidos a trasplante renal de noviembre de 1999 a enero de 2008, en quienes se llevó a cabo desensibilización pretrasplante renal. Resultados: Ocho pacientes presentaron aloinmunización (pruebas cruzadas positivas o panel reactivo de anticuerpos alto, PRA > 30 %). La desensibilización se realizó mediante sesiones de plasmaféresis con recambio de 1.5 volúmenes plasmáticos, y posterior a cada una se administró una dosis estándar de inmunoglubulina intravenosa (IVIG 5 g/dosis). La inmunosupresión se inició en la primera sesión de plasmaféresis con base en un inhibidor de calcineurinas (tacrolimus); en seis pacientes se añadió mofetil micofenolato y en dos, sirolimus. En siete se obtuvieron pruebas cruzadas negativas con el donador previo al trasplante; en el octavo no se efectuaron. En dos se administró anticuerpos humanizados contra CD25 (20 mg/dosis de basiliximab). Todos los pacientes han mantenido función estable del injerto. Conclusiones: De acuerdo con nuestra experiencia, la sobrevida del injerto renal en pacientes con alto riesgo inmunológico posterior a un adecuado protocolo de desensibilización y estrecha vigilancia postrasplante es similar a la observada en pacientes no sensibilizados, al menos durante el primer año del trasplante.

BACKGROUND: Patients with high immunological risk have been relegated to the growing waiting list for an immunologically compatible donor. Our objective was to report the experience of a transplant center in desensitization of patients with high immunological risk. METHODS: We carried out a descriptive and retrospective study. Included were all the renal transplant patients from November 1999 to January 2008 in which we used plasmapheresis and standard dose of intravenous immunoglobulin (IVIG) as desensitization. RESULTS: Eight patients had history of alloimmunity (positive crossmatch or high panel-reactive antibodies (PRA >30%). Desensitization was accomplished with plasmapheresis and exchange of 1.5 plasma volume. Subsequent to each session we administered a standard dose of IVIG (5 g/dose). Immunosuppression began equal to the first plasmapheresis with calcineurin inhibitor (tacrolimus) plus six patients with mycophenolate mofetil and two patients with sirolimus. In seven cases, negative crossmatches were obtained before the transplantation, except in the eighth case in whom it was not done. Two patients received human antibodies against CD25 (basiliximab, 20 mg/dose). During their evolution, all patients maintained stable graft function. CONCLUSIONS: According to our experience, renal graft outcome in patients with high immunological risk after an adequate desensitization protocol is similar to that observed in nonsensitized patients, at least during the first year of transplantation.

Comparison of the Frequencies and Distributions of Unexpected Antibodies Based on Different Calculation Criteria / 대한진단검사의학회지

BACKGROUND: The frequencies and distributions of unexpected antibodies have been reported using two different criteria, based on either number of persons tested or number of tests performed. But there has been no study that compared the results of analyses based on these two different criteria using the same data set. METHODS: Unexpected antibody tests performed in a University Hospital during recent 6 yr (January 2002-December 2007) were retrospectively analyzed: 76,985 tests (59,503 persons) for screening and 875 tests (749 persons) for identification. Data were analyzed using two different criteria, based on 'persons tested' and 'tests performed'. Antibodies had been screened and identified using LISS/Coombs gel cards with DiaMed-ID system (DiaMed AG, Switzerland). RESULTS: Frequencies of unexpected antibodies based on 'persons tested' and 'tests performed' were 1.32% and 1.34%, respectively (P=0.88). For frequently detected as well as rarely detected antibodies, there were no significant differences in the frequencies based on two different criteria. However, for rarely detected antibodies (anti-Xg(a) and Anti-E & D), the frequencies based on 'tests performed' were higher than those based on 'persons tested', affecting a change in the order of frequencies of antibodies detected. CONCLUSIONS: As there were no significant differences in the frequencies of unexpected antibodies calculated using two different criteria, both criteria can be used together for the patient population in our hospital. However, two criteria should be compared to validate the results for other populations.

A Hemolytic Transfusion Reaction due to Anti-Ku Antibody in a Patient with Knull Phenotype: The First Case in Korea / 대한진단검사의학회지

Knull phenotype completely lacks all Kell system antigens. Anti-Ku antibody is seen in immunized persons with Knull phenotype by transfusion or pregnancy. It can cause a fatal hemolytic transfusion reaction. A 66-yr-old male patient with liver cirrhosis visited emergency center due to acute bleeding. The patient was at hypovolemic shock status: his blood pressure was 80/50 mmHg, pulse rate was 110/min and hemoglobin level was 4.4 g/dL. Because of the presence of antibody against high incidence antigen, we could not find any compatible blood for the patient. Nevertheless, 4 units of packed RBCs had to be transfused. Moderate hemolytic transfusion reaction was developed after transfusion. At endoscopic examination, blood was spurting from gastric cardiac varix. Endoscopic histoacryl injection was tried, and bleeding was successfully controlled. After bleeding stopped, he was managed for anemia using steroid and other medical therapy instead of transfusion. His hemoglobin level was improved to 7.7 g/dL at the time of discharge. Later he has been proved to have a Knull phenotype, which is very rare, and anti-Ku antibody. This report is the first case of anti-Ku in a Knull phenotype person in Korea, who experienced a moderate hemolytic transfusion reaction.

Comparative Evaluation of ELISA and Luminex Panel Reactive Antibody Assays for HLA Alloantibody Screening / 대한진단검사의학회지

BACKGROUND: For the detection of HLA antibodies, solid-phase tests using purified HLA antigens are increasingly used. In this study, we analyzed the panel reactive antibody (PRA) test results using ELISA and Luminex methods, and the results were compared with those of crossmatch test. METHODS: A total of 111 sera including 90 sera from kidney transplanted patients were tested. ELISA-PRA was performed using Lambda Antigen Tray Class I and II Mixed kits (One Lambda Inc., USA) and additional test was performed to identify HLA specificities. Luminex-PRA tests were performed using LABScreen Mixed kits (One Lambda Inc., USA) and LIFECODES LifeScreen Deluxe kits (Tepnel Co., USA). RESULTS: The positive rates of PRA were higher in Tepnel (P=0.006) and One Lambda Luminex (P<0.001) methods than ELISA, without significant difference between two Luminex methods (P=0.087). The overall concordance rate among the three PRA tests was 62.2% (69/111). The positive and negative predictive values of PRA tests for the flow cytometric crossmatch were 33.3-45.7% and 85.7-89.5%, respectively. Of the two Luminex methods, One Lambda showed higher positive rate than Tepnel for the detection of class I antibodies. The sensitivity of pretransplant PRA for the detection of posttransplant acute rejection episodes was higher in Luminex (P=0.007 for Tepnel, P=0.003 for One lambda) than ELISA method. CONCLUSIONS: Different methods used to detect HLA antibodies showed discrepant results. As the Luminex method was more sensitive than ELISA for the detection of HLA antibodies, it can be used as a routine test in the transplantation laboratory.

Role of gel based technique for Coomb's test.

The direct (DAT) and indirect antiglobulin tests (IAT) are one of the most important diagnostic tools used in the investigation of immune mediated disorders. Recently, transfusion laboratories have seen the introduction of column technology in the form of the gel technology (GT). Aim of this study is to compare the conventional tube tests (CTT) and the GT for Coomb's test and to evaluate their sensitivity and specificity. 1656 samples were included in this study, in which 1054 samples were subjected to IAT and 602 samples were subjected to DAT Of the 602 samples tested for DAT, 587 (97.5%) showed concordant DAT results. DAT by the GT could detect 8.6% positivity as compared to 6.1% by CTT. The sensitivity and specificity of the GT was 100% and 97.3% respectively and its negative predictive value was 100%. Among the 1054 samples for IAT, 1041 (98. 8%) showed concordant results. The IAT by the GT showed 6.6% positivity as compared to 5.4% positivity by CTT The sensitivity, specificity and the positive and negative predictive value were 100%, 97.7%, 81.4% and 100% respectively. In conclusion, the GT is a better alternative to the CTT for both DAT and IAT. The GT is highly recommended to be implemented as a routine method of testing in all zonal / regional blood transfusion centers.

Anti Kell allo-antibody in a thalassaemic.

We describe a case of incidental detection of anti Kell antibody in a child with transfusion dependent thalassaemia. Kell antibody detection may be missed by routine indirect antiglobulin test (IAT) crossmatch procedure because of low prevalence of Kell antigen in the general population. A false negative result can be avoided by using sensitive cross matching techniques and screening cells representing antigens in homozygous state, against all clinically significant antibodies. A transfusion alert card describing the nature of antibody and future transfusion policy should be given to such allo-immunized patients.

A Case of Neonatal Alloimmune Neutropenia Associated with Anti-Human Neutrophil Antigen-1a (HNA-1a) Antibody

Neonatal alloimmune neutropenia (NAN) is an uncommon disease of the newborn provoked by the maternal production of neutrophil-specific alloantibodies, whereby neutrophil IgG antibodies cross the placenta and induce the destruction of fetal neutrophils. Affected newborns are usually identified by the occurrence of bacterial infections. The most frequent antigens involved in NAN are the human neutrophil antigen-1a (HNA-1a), HNA-1b, and HNA-2a. We report a neonate who was delivered at 36 weeks and had a severe neutropenia but who responded well to recombinant human granulocyte colony-stimulating factor (rhG-CSF). Anti-HNA-1a antibody was identified by mixed passive hemagglutination assay in both the sera of the baby and the mother. The baby had HNA-1a and HNA-1b but the mother had only HNA-1b on granulocytes. This is the first Korean report of NAN in which the specificity of the causative antibody was identified.

A Fatal Case of Severe Hemolytic Disease of Newborn Associated with Anti-Jk(b)

The Kidd blood group is clinically significant since the Jk antibodies can cause acute and delayed transfusion reactions as well as hemolytic disease of newborn (HDN). In general, HDN due to anti-Jk(b) incompatibility is rare and it usually displays mild clinical symptoms with a favorable prognosis. Yet, we apparently experienced the second case of HDN due to anti-Jk(b) with severe clinical symptoms and a fatal outcome. A female patient having the AB, Rh(D)-positive boodtype was admitted for jaundice on the fourth day after birth. At the time of admission, the patient was lethargic and exhibited high pitched crying. The laboratory data indicated a hemoglobin value of 11.4 mg/dL, a reticulocyte count of 14.9% and a total bilirubin of 46.1 mg/dL, a direct bilirubin of 1.1 mg/dL and a strong positive result (+++) on the direct Coomb's test. As a result of the identification of irregular antibody from the maternal serum, anti-Jk(b) was detected, which was also found in the eluate made from infant's blood. Despite the aggressive treatment with exchange transfusion and intensive phototherapy, the patient died of intractable seizure and acute renal failure on the fourth day of admission. Therefore, pediatricians should be aware of the clinical courses of hemolytic jaundice due to anti-Jk(b), and they should be ready to treat this disease with active therapeutic interventions.

Platelet alloimmunization in multitransfused patients with haemato-oncological disorders.

BACKGROUND: We studied the incidence of platelet alloimmunization in multitransfused patients with haemato-oncological disorders and determined the factors influencing alloimmunization. We also assessed the effect of alloimmunization on response to platelet transfusion. METHODS: Fifty patients with haemato-oncological disorders who received multiple transfusions were included. The patients were tested for antibodies before they received any transfusion and then after 3-4 weeks of transfusion. Lymphocytotoxicity and platelet immunofluorescence suspension tests were used to detect antiplatelet antibodies. Symptomatic improvement was used to assess the response to platelet transfusions. RESULTS: Thirty patients were positive by the lymphocytotoxicity test, giving an incidence of 60% for anti-HLA antibodies. The panel reactivity of the antibodies ranged from 3% to 100%. Nineteen patients were positive by the platelet immunofluorescence suspension test, 16 of whom were also positive by the lymphocytotoxicity test. The overall incidence of antiplatelet antibodies was 66%. The number of transfusions received and the underlying haemato-oncological disorder were not risk factors for the development of antibodies. Patients with a past history of transfusions and those with a positive obstetric history had a significantly higher incidence of antibodies. The response to transfusion therapy was poor in patients with antibodies, as 71.4% of patients with antibodies were nonresponsive compared to only 26.6% of antibody-negative patients. CONCLUSION: A high percentage of multitransfused patients developed antiplatelet antibodies. Previous sensitization was an important risk factor for the development of antibodies. Patients with high panel reactivity (HLA) showed non-responsiveness to platelet transfusions. Testing for the presence of antiplatelet antibodies and provision of compatible platelets should be important components in the management of patients with platelet transfusion refractoriness.

Risk factors for alloimmunization by patients with sickle cell disease

Blood transfusion in patients with sickle cell disease (SCD) is limited by the development of alloantibodies to erythrocytes. In the present study, the frequency and risk factors for alloimmunization were determined. Transfusion records and medical charts of 828 SCD patients who had been transfused and followed at the Belo Horizonte Blood Center, Belo Horizonte, MG, Brazil, were retrospectively reviewed. Alloimmunization frequency was 9.9 percent (95 percent CI: 7.9 to 11.9 percent) and 125 alloantibodies were detected, 79 percent of which belonged to the Rhesus and Kell systems. Female patients developed alloimmunization more frequently (P = 0.03). The median age of the alloimmunized group was 23.3 years, compared to 14.6 years for the non-alloimmunized group (P < 0.0001). Multivariate analyses were applied to the data for 608 hemoglobin (Hb) SS or SC patients whose number of transfusions was recorded accurately. Number of transfusions (P = 0.00006), older age (P = 0.056) and Hb SC (P = 0.02) showed independent statistical associations with alloimmunization. Hb SC patients older than 14 years faced a 2.8-fold higher (95 percent CI: 1.3 to 6.0) risk of alloimmunization than Hb SS patients. Female Hb SC patients had the highest risk of developing alloantibodies. In patients younger than 14 years, only the number of transfusions was significant. We conclude that an increased risk of alloimmunization was associated with older patients with Hb SC, specially females, even after adjustments were made for the number of transfusions received, the most significant variable.