Background: Infectious complications represent the main cause of morbidity and mortality in chronic lymphocytic leukemia. It has been reported that polymorphisms of the mannosebinding lectin 2 (MBL2) genes are correlated with MBL protein serum levels and, consequently, are associated with the development of infectious diseases. Objective: The purpose of this study was to investigate the possible association between MBL2 gene polymorphisms and risk of infection in chronic lymphocytic leukemia patients. Methods: Peripheral blood samples from 116 chronic lymphocytic leukemia patients were collected; after genomic DNA extraction, real time polymerase chain reaction was used to determine the polymorphisms of the promoter region and exon 1 of the MBL2 gene. Results: A high frequency of Binet stage A (p-value = 0.005) and absence of splenomegaly (p-value = 0.002) were observed in patients with no infection; however, variant alleles/ genotypes and haplotypes of this gene had no impact on the risk of infection. Conclusion: To the authors' knowledge, this is the first study describing the association between MBL2 polymorphisms and infectious disease in chronic lymphocytic leukemia. Although it was not possible to demonstrate any influence of MBL2 polymorphisms as a genetic modulator of infection in chronic lymphocytic leukemia, the authors believe that the present data are clinically relevant and provide the basis for future studies.

OBJETIVO: Estimar o incremento no número adicional de afetados com base na prevalência de síndromes falciformes em familiares de casos-índice. MÉTODOS: Estudo transversal em familiares de amostra aleatória dos casos-índice identificados por programa de triagem neonatal em Pernambuco, no período de 2001 a 2005. O modelo de triagem familiar ampliado incluiu 463 membros familiares de 21 casos-índice. Os familiares foram categorizados como: núcleo reduzido (NR -pai, mãe e irmãos); de primeiro grau (N1 - avós, tios e primos de primeiro grau); de segundo grau (N2 - filhos dos primos de primeiro grau); ampliado (NA - NR+N1+N2) e ampliado de primeiro grau (NA1 -NR+N1). A confirmação da presença de HBB*S e detecção de hemoglobinas anormais foram realizadas por meio da High Performance Liquid Chromathgraphy. A associação entre a presença de HBB*S e variáveis foi testada pelo cálculo da razão de prevalência e respectivos IC 95% e a diferença entre médias verificadas pelo teste t de Student, ao nível de significância de 5%. RESULTADOS: A anemia falciforme era desconhecida por 81% dos familiares; o gene HBB*S esteve presente em 114 familiares. Observou-se que 53,3% da população estudada estava na faixa considerada reprodutiva e 80% das pessoas portadoras do gene HBB*S já tinham gerado filhos. A freqüência foi maior no núcleo NR (69%), mas também elevada no N1 (22,8%). O NA1 resultou na detecção de 69 portadores adicionais (aumento de 172%). CONCLUSÕES: Os resultados indicam que a triagem familiar para identificação de portadores de síndrome falciforme deve ser estendida para os familiares até o primeiro grau.

OBJECTIVE: To estimate the additional number of affected individuals based on the prevalence of sickle-cell syndromes among relatives of index cases. METHODS: Cross-sectional study of relatives of a random sample of index cases identified through a neonatal screening program in Northeastern Brazil, between 2001 and 2005. The extended family trial model included 463 relatives of 21 index cases. Relatives were classified as nuclear family (NF: father, mother, and siblings); first degree extended family (N1: grandparents, uncles and aunts, and first cousins); second degree extended family (N2: children of first cousins); extended family (NA: NF+N1+N2); and extended nuclear family (NA1: NF+N1). The presence of HBB*S and other abnormal hemoglobins was confirmed by high-performance liquid chromatography. The association between the presence of HBB*S and other variables was calculated using prevalence ratios and their respective 95% confidence intervals, and differences between means were calculated using Student's t test with a 5% significance level. RESULTS: Of relatives, 81% had no knowledge of sickle-cell anemia and HBB*S was present in 114 family members. A total of 53.3% of the studied population was considered as of reproductive age, and 80% of HBB*S carriers had already had children. Frequency was higher among NF (69%), but was also high in N1 (22.8%). NA1 screening resulted in the detection of 69 carriers additional (a 172% increase). CONCLUSIONS: These results indicate that family screening for the identification of sickle-cell carriers should be extended to first degree relatives.

OBJETIVO: Estimar o incremento no número adicional de afetados com base na prevalência de síndromes falciformes em familiares de casos-índice. MÉTODOS: Estudo transversal em familiares de amostra aleatória dos casos-índice identificados por programa de triagem neonatal em Pernambuco, no período de 2001 a 2005. O modelo de triagem familiar ampliado incluiu 463 membros familiares de 21 casos-índice. Os familiares foram categorizados como: núcleo reduzido (NR -pai, mãe e irmãos); de primeiro grau (N1 - avós, tios e primos de primeiro grau); de segundo grau (N2 - filhos dos primos de primeiro grau); ampliado (NA - NR+N1+N2) e ampliado de primeiro grau (NA1 -NR+N1). A confirmação da presença de HBB*S e detecção de hemoglobinas anormais foram realizadas por meio da High Performance Liquid Chromathgraphy. A associação entre a presença de HBB*S e variáveis foi testada pelo cálculo da razão de prevalência e respectivos IC 95% e a diferença entre médias verificadas pelo teste t de Student, ao nível de significância de 5%. RESULTADOS: A anemia falciforme era desconhecida por 81% dos familiares; o gene HBB*S esteve presente em 114 familiares. Observou-se que 53,3% da população estudada estava na faixa considerada reprodutiva e 80% das pessoas portadoras do gene HBB*S já tinham gerado filhos. A freqüência foi maior no núcleo NR (69%), mas também elevada no N1 (22,8%). O NA1 resultou na detecção de 69 portadores adicionais (aumento de 172%). CONCLUSÕES: Os resultados indicam que a triagem familiar para identificação de portadores de síndrome falciforme deve ser estendida para os familiares até o primeiro grau.

OBJECTIVE: To estimate the additional number of affected individuals based on the prevalence of sickle-cell syndromes among relatives of index cases. METHODS: Cross-sectional study of relatives of a random sample of index cases identified through a neonatal screening program in Northeastern Brazil, between 2001 and 2005. The extended family trial model included 463 relatives of 21 index cases. Relatives were classified as nuclear family (NF: father, mother, and siblings); first degree extended family (N1: grandparents, uncles and aunts, and first cousins); second degree extended family (N2: children of first cousins); extended family (NA: NF+N1+N2); and extended nuclear family (NA1: NF+N1). The presence of HBB*S and other abnormal hemoglobins was confirmed by high-performance liquid chromatography. The association between the presence of HBB*S and other variables was calculated using prevalence ratios and their respective 95% confidence intervals, and differences between means were calculated using Student's t test with a 5% significance level. RESULTS: Of relatives, 81% had no knowledge of sickle-cell anemia and HBB*S was present in 114 family members. A total of 53.3% of the studied population was considered as of reproductive age, and 80% of HBB*S carriers had already had children. Frequency was higher among NF (69%), but was also high in N1 (22.8%). NA1 screening resulted in the detection of 69 carriers additional (a 172% increase). CONCLUSIONS: These results indicate that family screening for the identification of sickle-cell carriers should be extended to first degree relatives.