Riscontro occasionale di varianti emoglobiniche nel corso della determinazione di HbA1c in elettroforesi capillare: Hb Lepore.

The growing prevalence and heterogeneity of genetic variations of hemoglobin in the Italian population requires essential information about the patient condition for a correct diagnostic laboratory approach. Lack of anamnestic data could compromise the correct interpretation of the laboratory result. One example is the case of a 52-year-old man with a medical request of HbA_1c determination performed by the separative method in capillary electrophoresis (CE) with a result of 71 mmol/mol (r.i. 20-42). The separation of the Hb components with a dedicated CE method reported a minor peak of 1.1% in "(D) zone" and HbF 5.7% (.r.i. 0-1.1%). This peak was not identified with an alternative HPLC method, because of coelution with a HbA2 peak of 3.4% (r.i. 2.2-3.0). The blood count was not particularly altered except for a moderate anemia (hemoglobin=103 g/L; r.i. 140-175). The requesting clinician later informed the laboratory that the patient had been transfused many times for an undefined hemoglobinopathy. The subsequent molecular analysis revealed the presence of a hemoglobin variant, specifically Hb Lepore in homozygosis. This case allows to set out some considerations: first, the use of a separative method for HbA_1c makes it possible to observe atypical profile and therefore allows the measurement of glycated hemoglobin and the detection of possible Hb variants at the same time; second, the request for HbA_1c measurement in a transfused patients should be considered inappropriate; third, the absence of pre-test information may trigger presumptive and erroneous conclusions or useless and expensive laboratory second-level laboratory tests. [ABSTRACT FROM AUTHOR]