Abstract Introduction Sickle cell anemia is a monogenic disorder caused by a mutation in the β-hemoglobin gene, resulting in sickle hemoglobin that can polymerize. Presentation and clinical course have significant inter-individual variability and classifying these patients for severity is a challenge. Methods We applied hierarchical clusters with 10 routine laboratory tests to understand if this grouping could be associated with clinical manifestations. We included 145 adult homozygous patients (SS) at an outpatient clinic in a retrospective study. Results We found five clusters by counting those that had been differentiated by unconjugated bilirubin, reticulocytes, LDH, leukocytes, lymphocytes and monocytes. When comparing groups to clinical findings, the clusters were different only for liver abnormality. Cluster 3 had the lower median of reticulocytes, LDH, leukocytes, lymphocytes and monocytes and a higher percentage of patients under treatment. Clusters 4 and 5 had higher frequencies of liver impairment and higher medians of reticulocytes, LDH, leukocytes, lymphocytes and monocytes. Hemolysis and inflammation seemed to influence the grouping. Conclusion In our study, cluster analysis showed five groups that exhibited different degrees of inflammation and hemolysis. When comparing clinical data, the result was different only for the criteria of liver abnormality.

ABSTRACT Introduction: Platelet antibody identification is indispensable for diagnosing the human platelet antigen (HPA) or human leukocyte antigen (HLA) immunization, mostly because it can restrict the compatibility and results of transfusions. Correct detection of these antibodies is of utmost importance for the diagnosis and treatment. Method: We present 16 platelet alloimmunization results, comparing two tests with different technologies: the MAIPA (monoclonal antibody immobilization of platelet antigens), as a reference technique, and a bead-based assay, the Pak-Lx. Results: Eleven samples (68.75%) showed agreement in both techniques. Two tests were false negatives in the Pak-Lx: a pan-reactivity in GPIIbIIIa and an anti-HPA-9b. On the other hand, the Pak-Lx was more sensitive to detect a decreasing anti-HPA-5b. The Pak-Lx found an anti-HPA-2b positive, but with a low median fluorescent intensity (MFI), suggesting a false-positive result. Moreover, in one case, the MAIPA was negative for a positive Pak-Lx HLA. Conclusion: Antibody platelet diagnosis can sometimes be challenging. The methods seemed similar, the Pak-Lx being faster and simpler than the MAIPA, and they can be complementary to solve clinical issues.

RESUMO Objetivo Descrever as frequências alélicas e haplotípicas de genes dos antígenos leucocitários humanos nos loci -A,- B e dos antígenos plaquetários humanos para os sistemas HPA-1 a 9, 11 e 15. Métodos Foram incluídos 867 doadores voluntários, saudáveis, não relacionados, que doaram plaquetas por aférese entre janeiro de 2011 e dezembro de 2014. A genotipagem foi realizada usando microarray BeadChip. A tipificação de resolução intermediária dos antígenos leucocitários humanos loci A e B foi realizada por meio de hibridização com sonda para oligonucleotídeos por sequência específica. Utilizamos análises multivariadas e o antígeno leucocitário humano de nossa população foi comparado com a do programa nacional de doadores de medula óssea norte-americano. Já os resultados dos antígenos plaquetários humanos foram comparados à revisão da literatura e a dados de populações de outros países. Resultados Os resultados do haplótipo de antígenos leucocitários humanos são mais parecidos com os dos hispânicos, seguidos dos caucasianos. Igualmente, a amostra de antígenos plaquetários humanos foi mais semelhante às da Argentina, do Rio Grande do Sul e da Itália. Conclusão Este foi o primeiro artigo a discutir antígenos plaquetários e leucocitários humanos simultaneamente. Genótipos raros ou associações de anticorpos podem dificultar o manejo clínico do paciente. Um banco de sangue com doadores genotipados permite um melhor resultado e transfusão possíveis. Estas informações podem servir de base para um banco de dados sobre polimorfismos de antígenos plaquetários.

ABSTRACT Objective To described the allele and haplotype frequencies of human leukocyte antigen genes at the -A, -B loci and human platelet antigen genes for human platelet antigen systems 1 to 9, 11 and 15 in blood. Methods We included 867 healthy unrelated volunteer donors who donated platelets between January 2011 and December 2014. Microarray genotyping was performed using a BeadChip microarray. Medium resolution typing of the human leukocyte antigen at loci A and B was carried out using sequence-specific oligonucleotide probe hybridization. We used multivariate analysis and our human leukocyte antigen population was compared to data from the United States national bone marrow donor program. Human platelet antigen results were compared to a literature review and data from around the world. Results Our human leukocyte antigen haplotype results were more similar to those of hispanics, followed by caucasians. Likewise, our human platelet antigen sample is more similar to those of Argentina, Rio Grande do Sul and Italy. Conclusion This was the first article that discusses human platelet antigen and human leukocyte antigen data together. Rare genotypes or antibody associations can make patient management difficult. A blood bank with genotyped donors allows for optimal transfusion and can contribute to better results. Our information can serve as basis for a database of platelet antigen polymorphisms.