Sickle cell disease: laboratory investigations and hemoglobin study.

The diagnosis of any sickle cell disease syndrome is based on the unambiguo us identification of HbS, Electrophoretic tests are usually the first to be performed. A much better resolution is obtained with isoelectricfocusing t han with the more conventional cellulose acetate electrophoresis at alkalin e pH. In some laboratories the first test is cation exchange HPLC The diagn osis of HbS should never be accepted if not confirmed by a second test, mor e specific of this Hb such as the solubility test or electrophoresis on aga r in citrate buffer. The laboratory should also evaluate other factors interacting with HbS, suc h as HbF level, sickle cell restriction haplotype, association with alpha - thalassemias. It should also evaluate other cellular factors and, in case o f symptomatic heterozygous patients, help to understand of the underlying m echanisms.