RESUMO
Fundamento y objetivo: El control de la diabetes mellitus se realiza mediante la determinación de hemoglobina glucosilada (HbA1c) por cromatografía líquida de alta resolución. Algunas variantes estructurales de la hemoglobina (Hb) son conocidas por causar interferencia analítica en la medición de la HbA1c. Pacientes y métodos: En este estudio se ha caracterizado una nueva variante de Hb en 4 pacientes, que se detectó al realizarse un control de HbA1c. Resultados: La secuenciación selectiva del gen α1 mostró una mutación responsable del cambio de ácido aspártico (Asp) por asparagina (Asn) en el codón 64. El cambio de Asp por Asn no produce ninguna alteración funcional de la Hb y se comporta como una hemoglobinopatía silente. Conclusión: Las variantes estructurales de la Hb se pueden detectar durante la medición de la HbA1c y pueden alterar sus valores. Estos casos, aunque poco frecuentes, requieren examinar a fondo los cromatogramas para detectar posibles interferencias (AU)
Background and objective: The glycated hemoglobin (HbA1c) test by high performance liquid chromatography is a useful tool for the follow-up of diabetes mellitus patients. Some structural hemoglobin (Hb) variants are known to cause interference in the analytical measurement of HbA1c. Patients and methods: In this study, it has been characterized a new Hb variant in 4 patients during their regular control of HbA1c. Results: Selective α1 gene sequencing showed a mutation GAC > AAC at codon 64 within exon 2. This produces a change of aspartic acid (Asp) by asparagine (Asn) that does not produce any functional alteration so the resultant molecule behaves as a silent hemoglobinopathy. Conclusion: The structural Hb variants can be detected during the analysis of HbA1c and may alter its values. Though rare, this occurrence signals the need to being aware when measuring HbA1 (AU)
Assuntos
Humanos , Diabetes Mellitus/fisiopatologia , Hemoglobinas Glicadas/análise , Hemoglobinopatias/fisiopatologia , Sequência de Bases/genética , Cromatografia Líquida de Alta PressãoRESUMO
BACKGROUND AND OBJECTIVE: The glycated hemoglobin (HbA1c) test by high performance liquid chromatography is a useful tool for the follow-up of diabetes mellitus patients. Some structural hemoglobin (Hb) variants are known to cause interference in the analytical measurement of HbA1c. PATIENTS AND METHODS: In this study, it has been characterized a new Hb variant in 4 patients during their regular control of HbA1c. RESULTS: Selective α1 gene sequencing showed a mutation GAC>AAC at codon 64 within exon 2. This produces a change of aspartic acid (Asp) by asparagine (Asn) that does not produce any functional alteration so the resultant molecule behaves as a silent hemoglobinopathy. CONCLUSION: The structural Hb variants can be detected during the analysis of HbA1c and may alter its values. Though rare, this occurrence signals the need to being aware when measuring HbA1c.
