[Detection campaign for hemoglobinopathies and thalassemias among school children in northern Extremadura]

Abstract

Purpose: To detect carriers of thalassaemia and haemoglobin variants among the northern Extremadura school population.

Material and methods: The study was carried out in the Plasencia health service area, comprising about 120,000 people. All children between 4 and 15 years of age were offered to take part in the programme. The first-stage screen was mean corpuscular volule (MCV) measured in a Coulter STKS automatic counter. When low VCM was detected, ferritin estimation was carried out; if ferritin was normal, hemoglobin A2 was quantified. Haemoglobin electrophoresis at pH 8.4 was performed in all samples whatever the MCV, and patients were classified into the following groups: iron deficiency, beta-thalassaemia, Hb Lepore, structural haemoglobin variant, or atypical microcytosis.

Results: Out of 22 schools from 20 towns, 2,818 children were studied, the participation reaching 75.48%. Lower than normal MCV was found in 162 children (5.74%), who were grouped as follows: thalassaemia, 15 cases (0.53%), Hb Lepore, 8 cases (0.28%), iron deficiency, 77 cases (2.73%), atypical microcytosis, 55 cases (1.95%), and structural variants 7 cases (0.24%). These variants were further identified as HbS (3), Hb Hofu (1), in natives, and HbC (3) in children from Morocco. Higher prevalence of anomalies was seen in some places: Riolobos, 1.5%, Galisteo, 2.5%, Jaraiz de la Vera, 3.02%; a significant group of Hb Lepore carriers was detected in this last town.

Conclusions: The prevalence of abnormalities seen in some small towns or villages grants this type of programmes as such places, which could be considered as isolated communities, might provide a number of high-risk couples.