Time between inhibitor detection and start of immune tolerance induction: Association with outcome in the BrazIT study.

BACKGROUND: Immune tolerance induction (ITI) is the treatment of choice for eradication of anti-factor VIII (FVIII) neutralizing alloantibodies (inhibitors) in people with inherited hemophilia A and high-responding inhibitor (PwHA-HRi). The association between ITI outcome and time elapsed between inhibitor detection and start of ITI (∆tinhi-ITI ) is debatable. OBJECTIVE: The aim of this study was to evaluate this association among a large cohort of severe PwHA-HRi. METHODS: Severe (factor VIII activity level <1%) PwHA-HRi on ITI (n = 142) were enrolled in 15 hemophilia treatment centers. PwHA-HRi were treated according to the Brazilian ITI Protocol. ITI outcomes were defined as success (i.e., recovered responsiveness to exogenous FVIII) and failure (i.e., no responsiveness to exogenous FVIII and requirement of bypassing agents to control bleeding). RESULTS: Median ages at inhibitor detection and at ITI start were 3.2 years (interquartile range [IQR], 1.6-8.1) and 6.9 years [IQR, 2.6-20.1), respectively. PwHA-HRi were stratified according to ∆tinhi-ITI quartiles: first (0.0-0.6 year), second (>0.6-1.7 year), third (>1.7-9.2 years), and fourth quartile (>9.2-24.5 years). The overall success rate was 65.5% (93/142), with no difference among first, second, third, and fourth quartiles (62.9%, 69.4%, 58.3%, and 71.4%, respectively) even after adjusting the analyses for potential confounders. CONCLUSION: In conclusion, delayed ITI start is not associated with failure of ITI in PwHA-HRi. Therefore, ITI should be offered for these patients, regardless of the time elapsed between the detection of inhibitor and the ITI start.

Socioeconomic and demographic characteristics of sickle cell disease patients from a low-income region of northeastern Brazil.

OBJECTIVE: To characterize the socioeconomic and demographic aspects of sickle cell disease patients from the state of Rio Grande do Norte (RN), Northeast Brazil, and their adherence to the recommended treatment. METHODS: This cross-sectional descriptive study was performed at referral centers for the treatment of hematological diseases. One hundred and fifty-five unrelated individuals with sickle cell disease who went to these centers for outpatient visits were analyzed. All the patients, or their caregivers, were informed about the research procedures and objectives, and answered a standardized questionnaire. RESULTS: The patients were predominantly younger than 12 years old, self-declared as mulatto, lived in small towns fairly distant from the referral center, and had low education and socioeconomic levels. Individuals who were ten or younger were diagnosed at an earlier age. Almost 50% of the patients were taking hydroxyurea, 91.4% reported having received pneumococcal/meningococcal vaccinations and 76.1% received penicillin as antibiotic prophylaxis. However, the majority of them reported having difficulties following the recommendations of the physicians, mainly in respect to attaining the prescribed medications and transportation to the referral centers. CONCLUSION: These individuals have a vulnerable socioeconomic situation that can lead to an aggravation of their general health and thus deserve special attention from the medical and psychosocial perspectives. Thus, it is necessary to improve public policies that provide Brazilian sickle cell disease patients with better access to medical treatment, living conditions, and integration into society.

Determination of ß haplotypes in patients with sickle-cell anemia in the state of Rio Grande do Norte, Brazil.

ß(S) haplotypes were studied in 47 non-related patients with sickle-cell anemia from the state of Rio Grande do Norte, Brazil. Molecular analysis was conducted by PCR/RFLP using restriction endonucleases XmnI, HindIII, HincII and HinfI to analyze six polymorphic sites from the beta cluster. Twenty-seven patients (57.5%) were identified with genotype CAR/CAR, 9 (19.1%) CAR/BEN, 6 (12.8%) CAR/CAM, 1 (2.1%) BEN/BEN, 2 (4.3%) CAR/Atp, 1 (2.1%) BEN/Atp and 1 (2.1%) with genotype Atp/Atp. The greater frequency of Cameroon haplotypes compared to other Brazilian states suggests the existence of a peculiarity of African origin in the state of Rio Grande do Norte.

Determination of beta S haplotypes in patients with sickle-cell anemia in the state of Rio Grande do Norte, Brazil

βS haplotypes were studied in 47 non-related patients with sickle-cell anemia from the state of Rio Grande do Norte, Brazil. Molecular analysis was conducted by PCR/RFLP using restriction endonucleases XmnI, HindIII, HincII and HinfI to analyze six polymorphic sites from the beta cluster. Twenty-seven patients (57.5 percent) were identified with genotype CAR/CAR, 9 (19.1 percent) CAR/BEN, 6 (12.8 percent) CAR/CAM, 1 (2.1 percent) BEN/BEN, 2 (4.3 percent) CAR/Atp, 1 (2.1 percent) BEN/Atp and 1 (2.1 percent) with genotype Atp/Atp. The greater frequency of Cameroon haplotypes compared to other Brazilian states suggests the existence of a peculiarity of African origin in the state of Rio Grande do Norte.

[Prevalence of abnormal hemoglobins in newborns in Natal, Rio Grande do Norte, Brazil]. / Prevalência de hemoglobinas anormais em recém-nascidos da cidade de Natal, Rio Grande do Norte, Brasil.

Hemoglobinopathies are among the most prevalent hereditary diseases in humans. Studies in different areas of Brazil have identified the prevalence of S and C abnormal hemoglobins. The study analyzed 1,940 cord blood samples of newborns from maternity hospitals in Natal, Rio Grande do Norte State, to investigate the prevalence of abnormal hemoglobins. All samples were submitted to cellulose acetate electrophoresis using a Tris-EDTA-borate buffer at pH 8.5. Electrophoresis in agar gel pH 6.2 was performed on samples presenting abnormal hemoglobin. Some 37 (1.91%) of the newborns presented hemoglobinopathies, as follows: 29 (1.50%) sickle cell trait (Hb FAS), 6 (0.31%) heterozygous Hb C (Hb FAC), one (0.05%) homozygous Hb S (Hb FS), and one (0.05%) Hb Barts suggestive of alpha thalassemia. The results show the need to implement screening for hemoglobinopathies in the neonatal population.

Prevalência de hemoglobinas anormais em recém-nascidos da cidade de Natal, Rio Grande do Norte, Brasil / Prevalence of abnormal hemoglobins in newborns in Natal, Rio Grande do Norte, Brazil

As hemoglobinopatias estão incluídas dentre as doenças hereditárias mais freqüentes nas populações humanas. Estudos realizados em diferentes regiões do Brasil têm demonstrado que as hemoglobinas anormais S e C são as mais prevalentes. Com o objetivo de investigar a prevalência de hemoglobinas anormais no período neonatal, foram analisadas 1.940 amostras de sangue de cordão umbilical provenientes de recém-nascidos de três maternidades da cidade de Natal, Rio Grande do Norte. Todas as amostras foram submetidas à eletroforese de hemoglobina em acetato de celulose utilizando tampão Tris-EDTA-Borato pH 8,5. As amostras que apresentaram hemoglobinas anormais foram submetidas à eletroforese em gel de ágar pH 6,2 para confirmação. Foram identificadas 37 (1,91 por cento) amostras com hemoglobinas anormais, das quais 29 (1,50 por cento) com traço falciforme (Hb FAS), 06 (0,31 por cento) com Hb C, uma (0,05 por cento) com anemia falciforme (Hb FS) e uma (0,05 por cento) apresentou Hb Bart's, sugerindo alfa talassemia. Os resultados encontrados evidenciam a necessidade de implantação da triagem de hemoglobinopatias em recém-nascidos na nossa população.

Aloimunização eritrocitária em pacientes portadores de anemia falciforme / Red blood alloimmunization in sickle cell anemia patients

A anemia falciforme é uma doença hereditária na qual as moléculas de hemoglobina estão geneticamente alteradas. Ocorre quando o indivíduo herda o gene S para a hemoglobina e esta herança é homozigótica, ou seja, Hb SS. O defeito genético é devido a uma mutação no cromossomo 11 que se constitui basicamente na substituição do ácido glutâmico pela valina na posição 6 do segmento A da cadeia polipeptídica beta. Os pacientes com anemia falciforme, tem crises dolorosas pelos microinfartos decorrentes do afoiçamento in vivo, tem suscetibilidade aumentada às infecções e tem significativa diminuição de sobrevida. O tratamento das complicações é feito principalmente com hidratação por via oral e/ou endovenosa, manutenção da boa diurese e o combate à acidose e, quando este não resolve, faz-se necessário a transfusão sanguínea expondo o paciente a diversas situações indesejáveis como aloimunização provocada pela exposição do paciente à diferentes antígenos eritrocitários causando a produção de anticorpos específicos contra estes antígenos. O presente trabalho teve como objetivo determinar a prevalência de anticorpos eritrocitários irregulares em pacientes portadores de anemia falciforme. Foram testados 31 soros de pacientes do HEMONORTE e Hospital Infantil Varela Santiago (H.I.V.S.) com idades variando entre 1 e 47 anos, no período de março de 1998 a fevereiro de 1999. Estes soros foram testados pelo gel teste centrifugação Liss/Coombs para a pesquisa de anticorpo irregular (P.A.I.) e, quando positivo, utilizou-se para a identificação do anticorpo irregular (I.A.I.), o painel de hemácias em 2 meios: Liss/Coombs e Papaína. A prevalência do anticorpo irregular foi de 3,2% (anti-S), concluindo-se que este baixo índice encontrado pode ter sido devido a pouca idade dos pacientes (maioria jovens) e a realização de um tratamento baseado na hidratação, no combate a dor e na oxigenoterapia evitando-se ao máximo as transfusões.

Estudo de uma família portadora de hemoglobina S / Study of a family carrier of hemoglobin S

Foi realizado um estudo em uma família natural do estado do Rio Grande do Norte (Brasil) com o objetivo de pesquisar a presença de hemoglobina S. Nesta Família constituída de 14 membros, a presença dessa hemoglobina foi pesquisada através do teste de falcizaçäo das hemácias e pela eletroforese de hemoglobina em acetato de celulose. Outros dados hematológicos foram obtidos pelos métodos rotineiros e, paralelamente, foram realizados exames clínicos com o objetivo de evidenciar sinais físicos relacionados com a presença da hemoglobina S. Constatou-se que a presença da hemoglobina S estava presente em alguns membros da família na forma heterozigoto (Hb-AS) tais como o avô materno, a avó paterna, ambos os pais e 3 dos filhos do casal e apenas um membro era portador dessa hemoglobina na forma homozigoto (Hb-SS)