Incidental finding of rare hemoglobin: hemoglobin Bari in northeast Spain.

Objectives: Cation exchange high-performance liquid chromatography (HPLC) is one of the techniques available for determining glycated hemoglobin (HbA1c) and also the method of choice for structural hemoglobinopathies screening. The objective of this case is to show how in a routine HbA1c test it is possible to incidentally find a hemoglobinopathy. Case presentation: In a routine blood analysis, an abnormal value for the hemoglobin A2 (HbA2) was obtained during the study of HbA1c with HPLC on the ADAMS™ A1c HA-8180T. After suspecting it could be due to the presence of a hemoglobinopathy, the study of possible variants was expanded using electrophoresis and HPLC on the Hydrasys and Variant II analysers, respectively. Since it could not be identified by these conventional methods, a genetic study was also carried out using Sanger sequencing. The patient presented a low HbA2 (1.3 %) and a 24.9 % variant with a retention time of 1.95 min, compatible with alpha-globin chain variant. In the genetic study, the pathogenic variant c.138C>G was detected in the HbA2 gene in heterozygosis, which resulted in the expression of the structural hemoglobinopathy known as hemoglobin Bari. Conclusions: The initial screening for structural hemoglobinopathies allows its identification or suspicion especially when it was performed with HbA1c analysis, requiring subsequent confirmation and diagnosis by other techniques.

Evaluación de la inmunofijación sérica frente al cociente de cadenas ligeras libres Kappa/Lambda en la confirmación de componentes monoclonales de baja concentración / Evaluation of serum immunofixation compared to the free Kappa/Lambda light chains ratio for confirming low monoclonal component concentrations

Introducción. La electroforesis de proteínas séricas (EFs) constituye, por norma general, el primer paso en la búsqueda de componentes monoclonales (CM). Una baja concentración de CM dará lugar a pequeños picos en la EFs que pueden hacer sospechar la existencia de una gammapatía monoclonal de significado incierto (GMSI). Para confirmar estas GMSI se ha utilizado la inmunofijación sérica (IFs) y un cociente de cadenas ligeras libres séricas (CLLs) Kappa (K)/Lambda (λ) alterado. Materiales y métodos. De 3.683 EFs realizadas en nuestro laboratorio durante los meses de febrero a noviembre de 2011, se observaron 165 con pequeños picos en las fracciones β1, β2 o gamma. La confirmación del CM se realizó mediante la IFs y la existencia de un cociente de CLLs K/ λ alterado. Resultados. De las 165 EFs seleccionadas para el estudio, la IFs fue positiva en 82, mientras que un cociente de CLLs K/λ alterado solo se observó en 11 de los 82. El cociente de CLLs K/λ de las 71 EFs restantes con IFs positivas, estuvo dentro del intervalo de normalidad para sujetos sanos (0.25-1.65). Conclusiones. La EFs constituye el primer paso en la búsqueda del CM, aunque esta interpretación está ligada a un cierto grado de subjetividad cuando estos CM están a baja concentración. Al valorar la utilidad de la IFs frente al cociente de CLLs K/λ en la confirmación de estos CM, se observó que la confirmación debe realizarse por IFs ya que la cuantificación del cociente de CLLs K/λno resultó útil (AU)

Introduction. Serum protein electrophoresis (SPE) is the first step in the search for a monoclonal component (MC). A low concentration of MC will give small spikes in the SPE, which may lead to the suspicion of a monoclonal gammopathy of undetermined significance (MGUS). To confirm these MGUS, serum immunofixation (sIFE) and abnormal serum free light chains (sFLC) Kappa/Lambda ratio have been used. Material and methods. Of 3683 SPE carried out in our laboratory during the months from February to November of 2011, we observed 165 small spikes in the SPE in β1, β2 or gamma region. The confirmation of these MGUS was made using sIFE and abnormal sFLC Kappa (K)/Lambda (λ) ratio. Results. Of 165 SPE selected for the study, sIFE was positive in 82, while an abnormal sFLC K/λ ratio alone was observed in 11 of the 82. The sFLC K/λ ratio of the 71 SPE remaining with positive sIFE was inside the interval of normality for healthy people (0.25-1.65). Conclusion. SPE is the first step in the search for a MC. When there is a low concentration of MC, this interpretation has a certain grade of subjectivity. When we evaluated the utility of sIFE versus sFLC K/λ ratio in the confirmation of these MC, it was observed that the confirmation should be carried out by means of sIFE since the quantification of the sFLC K/λ ratio was not useful (AU)