RESUMO
Los alelos deficitarios más frecuentes son los Pi*S y Pi*Z, pero existen también otras variantes deficientes. En la presente nota clínica se describen los 2 primeros casos detectados en España de déficit de alfa-1-antitripsina (DAAT), resultante de la combinación de un alelo nulo Mattawa con un normal PI*M y con un raro Mmalton. Ambos casos fueron inicialmente diagnosticados como Pi*MM por isoelectroenfoque (IEE), pero los valores séricos bajos de AAT hicieron sospechar la existencia de alelos deficientes infrecuentes indetectables por IEE, por lo que se realizó un análisis molecular del gen que proporcionó el diagnóstico correcto. Las incoherencias entre los valores séricos de AAT y el fenotipo deben hacer sospechar la existencia de uno de estos alelos infrecuentes (AU)
The most common deficiency alleles for alpha-1-antitrypsin deficiency (AATD) are Pi*S and Pi*S, but there are also other deficiency variants. This case report describes the first two cases of AATD detected in Spain resulting from the combination of a null Mattawa allele with a normal PI*M, and a rare Mmalton. Both cases were initially diagnosed as Pi*MM by isoelectric focusing (IEF), but the low serum AAT values led us to suspect the existence of rare deficiency alleles that were undetectable using this technique, and to performing molecular analysis of the gene, which provided the correct diagnosis. Inconsistencies between serum AAT values and the phenotype should make one suspect the existence of one of these rare alleles (AU)
Assuntos
Humanos , Deficiência de alfa 1-Antitripsina/genética , Alelos , Fenótipo , Registros de Doenças/estatística & dados numéricosRESUMO
The most common deficiency alleles for alpha-1-antitrypsin deficiency (AATD) are Pi*S and Pi*S, but there are also other deficiency variants. This case report describes the first two cases of AATD detected in Spain resulting from the combination of a null Mattawa allele with a normal PI*M, and a rare Mmalton. Both cases were initially diagnosed as Pi*MM by isoelectric focusing (IEF), but the low serum AAT values led us to suspect the existence of rare deficiency alleles that were undetectable using this technique, and to performing molecular analysis of the gene, which provided the correct diagnosis. Inconsistencies between serum AAT values and the phenotype should make one suspect the existence of one of these rare alleles.
