Article

Comparação de metodologia utilizada para a detecção de Hemoglobina S (Hb S) em doadores de sangue

Revista Brasileira de Hematologia e Hemoterapia 01/2000; DOI: 10.1590/S1516-84842000000200006
Source: DOAJ

ABSTRACT O Brasil apresenta alta prevalência de hemoglobina S, com nítidas diferenças regionais marcadas pelos processos de miscigenação da população. A presença desta hemoglobina tem sido objeto de estudo, não só em pacientes com anemia falciforme (homozigotos para hemoglobina S - Hb SS), mas também em portadores desta variante de hemoglobina em heterozigose (Hb AS). As complicações clínicas dos portadores são influenciadas por fatores genéticos e ambientais. De acordo com a portaria 1376 de 19 de novembro de 1993 para Normas técnicas de coleta, processamento e transfusão de sangue, componentes e derivados, do Ministério da Saúde, deve ser realizada a detecção de hemoglobinas anormais em doadores de sangue. Diante desta normatização e às taxas de hemoglobina S em nossa população, objetivamos no presente trabalho a identificação da hemoglobina S, utilizando técnicas de triagem utilizadas na rotina de Bancos de Sangue, como o kit de identificação para hemoglobina S da Diamed, comercializado pela designação ID-Hb S, e o teste de solubilidade. Os casos que apresentaram positividade nesta triagem foram posteriormente confirmados em eletroforese em pH alcalino e ácido. Do total de 5.416 doadores de sangue analisados pelo teste de triagem (ID - Hb S Diamed e solubilidade), 50 (0,92%) apresentaram hemoglobina S. Após confirmação eletroforética evidenciamos a compatibilidade das técnicas em 100 % dos casos analisados. O teste da Diamed apresenta custo de R$ 1,20 por doador e o de solubilidade R$ 0,14. Pelos resultados obtidos sugerimos o uso do teste de solubilidade como de escolha, para triagem de hemoglobina S em bancos de sangue, não só pela eficácia e praticidade, como também pelo baixo custo.

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