[Beta-thalassemia major in children and adolescents in Denmark]

Beta-thalassemia major occurs with increasing frequency among Danish children as a result of immigration. The aim of the study was to estimate the occurrence of beta-thalassemia major in Denmark, analyse the treatment and organ functions, and identify areas for an improved treatment strategy.

During 1998-99 all Danish pediatric departments were contacted for identification of children aged 0-18 years with beta-thalassemia major. Blood transfusions and chelation therapy were registered, and for Eastern Denmark clinical, endocrine, cardiac, and serologic parameters were performed.

Twenty-six children had beta-thalassemia major. Out of these, 20 received blood transfusions, and 17 patients were chelated. Eight patients were not chelated owing to previous bone marrow transplantation, treatment with hydroxyurea or ferritin < 2000 micrograms/l and young age. One patient had died. The body height was between 1.5 and -5.4 SDS (median -1.7) and the sitting height was -0.6 to -5.6 SDS (median -2.3). The bone age was delayed 1-5 years (median -2.5) in six out of ten examined patients, and puberty delayed in four out of five. A dilated left ventricle was documented in one out of eight patients examined. All patients were HIV and hepatitis C negative. For 75% of the children, the parents were related.

Children and adolescents with beta-thalassemia major in Denmark experience major heterogenicity with regard to treatment and late effects. An earlier and more effective iron chelation therapy together with improved patient support may reduce growth disturbances and endocrine and cardiac late effects.