Hemoglobinopathies in the Constantine region: frequency and difficulties in diagnosing rare variants

Aims. Hemoglobinopathies are among the most frequent genetic diseases in the world. Algeria has some endemic areas, mainly for β-thalassemia and sickle-cell anemia, but some rarer variants are sometimes found, whose diagnosis is difficult and may escape interpretation. The aim of this work is to shed light on the cases of rare hemoglobinopathies observed in the Constantine region and the difficulties encountered in their diagnosis. Material and methods. This is a descriptive crosssectional study of 517 capillary hemoglobin electrophoresis profiles on Capillarys and MINICAP Flex Piercing (SEBIA) machines, performed as part of the diagnosis or follow-up of hemoglobinopathies in the hemobiology/blood transfusion department of Constantine University Hospital. Diagnosis is based on clinical findings, blood count results and other biological parameters, family investigation, and hemoglobin studies. Result. 71% of the profiles studied were pathological, 26.70% of pathological cases were thalassemic syndromes, of which 26.53% were homozygous β-thalassemia and 67.35% heterozygous, 02 cases of heterozygous δ-thalassemia and 04 cases of heterozygous δβ-thalassemia, 73.3% of pathological profiles were hemoglobinoses, of which 58.74% had a major sickle cell syndrome (SS, Sβthal, SC), 24.54% with heterozygous sickle cell disease, 06.69% with heterozygous hemoglobinosis C and 05 homozygous hemoglobinosis C cases, one C/βthal and 02 C/α thal cases, 02 composite S/PHHF cases and 02 S/O-Arab cases, 02 composite S/D cases, 02 S/αthal cases, 03 heterozygous PHHF cases, one heterozygous O-Arab case, one heterozygous hemoglobinosis D case, 03 heterozygous lepore cases and 03 heterozygous hemoglobinosis J cases. Conclusion: a precise diagnosis of rare hemoglobin variants is not always obvious, and sometimes only molecular study can provide it.