title: Different forms of Hb Le Lamentin. An unexpected finding in Hba1c quantification.
abstract: OBJECTIVE
  Glycated hemoglobin (HbA1c) is accepted as the most trusted marker for monitoring patients with diabetes mellitus. Ion-exchange high-performance liquid chromatography (HPLC) is one of the most widely used methods for HbA1c analysis. The presence of a hemoglobin variant can interfere with HbA1c quantification, requiring other analyses to clarify the results.Herein, we present two cases of Hb Le Lamentin, which, although they were the same variant, were thought to correspond to different hemoglobinopathies because of their percentages.
  
  
  METHODS
  Two male patients presented with an anomalous peak between HbA1c and HbA0 during a routine analysis of HbA1c using ion-exchange HPLC (Variant™ II Turbo).The hemoglobin variants were studied using capillary zone electrophoresis with the Sebia system, and the globin chains were analyzed by reverse-phase HPLC. A genetic analysis was performed using automated sequencing of the α2 and β genes.
  
  
  RESULTS
  In this work, we describe the first case of homozygous Hb Le Lamentin and the first double-heterozygous case of Hb Le Lamentin/Hb City of Hope.
  
  
  CONCLUSIONS
  Although the presence of these variants does not lead to clinical anomalies, it also does not affect hematologic parameters. The variants have an impact on the determination of glycated hemoglobin levels using ion-exchange HPLC because the retention time interferes with the elution time of HbA1c, resulting in a falsely reduced value. Therefore, it is necessary to either recalculate the result or use another measurement method.
authors.affiliation: Servicio de Análisis Clínicos. Hospital General de Albacete, Spain.
authors.forename: Rosalina
authors.initials: R
authors.lastname: Martínez-López
authors.affiliation: Servicio de Hematología y Hemoterapia. Hospital Clínico San Carlos Madrid, Spain.
authors.forename: Félix
authors.initials: F
authors.lastname: de la Fuente-Gonzalo
authors.affiliation: Servicio de Hematología y Hemoterapia. Hospital Clínico San Carlos Madrid, Spain.
authors.forename: Jorge M
authors.initials: JM
authors.lastname: Nieto
authors.affiliation: Servicio de Análisis Clínicos. Hospital General de Albacete, Spain.
authors.forename: Cristina Ballesteros
authors.initials: CB
authors.lastname: Gallar
authors.affiliation: Servicio de Análisis Clínicos. Hospital General de Albacete, Spain.
authors.forename: Carlos Romero
authors.initials: CR
authors.lastname: Román
authors.affiliation: Servicio de Hematología y Hemoterapia. Hospital Clínico San Carlos Madrid, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Villegas
authors.affiliation: Servicio de Hematología y Hemoterapia. Hospital Clínico San Carlos Madrid, Spain.
authors.forename: Fernando A
authors.initials: FA
authors.lastname: González
authors.affiliation: Servicio de Hematología y Hemoterapia. Hospital Clínico San Carlos Madrid, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Martínez
authors.affiliation: Servicio de Análisis Clínicos. Hospital General de Albacete, Spain.
authors.forename: Laura Navarro
authors.initials: LN
authors.lastname: Casado
authors.affiliation: Servicio de Hematología y Hemoterapia. Hospital Clínico San Carlos Madrid, Spain. Electronic address: paloma.ropero@salud.madrid.org.
authors.forename: Paloma
authors.initials: P
authors.lastname: Ropero
mesh_terms: D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D019075:Electrophoresis, Capillary; D006442:Glycated Hemoglobin / Q000032:analysis*; D006455:Hemoglobins, Abnormal / Q000737:chemistry*; D006801:Humans; D008297:Male; D008875:Middle Aged
chemical_list: D006442:Glycated Hemoglobin; D006455:Hemoglobins, Abnormal; C035852:hemoglobin Le Lamentin