Hemoglobin Sickle-Lepore: An Unusual Case of Sickle Cell Disease

Hemoglobinopathies δβ fusion gene Hb S/Hb Lepore M. Romana, Unite de Recherche sur la Drépanocytose, INSERM U-359, Centre Hospitalier Universitaire, BP 465, F-97159 Pointe-à-Pitre Cedex, Guadeloupe (France), Tel. (590) 383 48 99, fax (590) 383 05 13 Hemoglobin LeporeWashington-Boston is a ß-globin structural variant, produced in a reduced amount and formed from the fusion of N-terminus δ-chains (residues 1-87) and C-terminus ßchains (residues 116-146) [1]. The double heterozygous condition for sickle and Lepore hemoglobins (Hb S/Hb Lepore) gives rise to a sickle hemoglobi-nopathy rarely described in the literature. In this report, we describe a family from Guadeloupe (French West Indies) in which one child is a compound heterozygote for Hb S and Hb LeporeWashington-Boston· The propositus is a 10-year-old male born in Guadeloupe. He was noted at birth to have an FS pattern on isoelectrofocusing and HPLC. At the age of 6 months, a family study was performed. Peripheral blood parameters were determined on an automatic analyzer and hemoglobin electrophoresis was carried out by standard methods. The F cells were assayed by a microscopic immunofluor-escent method using a monoclonal antibody raised against human γ-globin chain. The hemoglobin pheno-type of the father was typical for sickle cell trait. The pattern of the mother of the propositus was AA on citrate agar but showed an A’SA.2 pattern on isoelectrofocusing. The hemoglobin in the S position accounted for approximately 10% of the total hemoglobin. She had a modest fetal hemoglobin level with 4.6% and a heterocellular distribution of F cells (18.3%), in agreement with the ß-thal-assemic-like condition of the Hb Lepore gene. Moreover, she presented slight microcytosis (MCV = 78.0 fl) and hypochromia (MCH = 26.3 pg). At the age of 9 years, the proband had mild hypochromic (MCH = 23.8 pg) micro-cytic anemia (Hb =