LAUSR

A 59yearold man, referred for unexplained iron overload and suspected Gilbert syndrome, had been under followup for 6 years. His blood count showed mild normocytic nonregenerative anaemia (haemoglobin concentration 123 g/l). Serum ferritin (680 μg/l) and transferrin saturation (46.9%) were elevated. Clinical examination was normal. Molecular genetic testing for hereditary haemochromatosis was negative (no pathogenic mutation was found in HFE, HJV, HAMP, TFR2, BMP6 or SLC40A1). He had evidence suggesting haemolysis (haptoglobin <0.1 g/l) and was jaundiced (total bilirubin: 27 μmol/l) with negative screening for red cell defects (including molecular analysis of α and β globin genes) and for extracorpuscular causes of haemolysis. He had never been transfused and had been treated by phlebotomy to control liver iron concentration – measured by magnetic resonance imaging (MRI) (95 μmol/g vs. 170 μmol/g one year earlier). Bone marrow aspiration was performed and revealed erythroid hyperplasia (73%) with 20% bior multinucleated erythroid precursors (MayGrünwaldGiemsa, ×100 objective). These morphological changes were highly suggestive of congenital dyserythropoietic anaemia type II (CDA II). Genetic molecular study revealed an SEC23B mutation and confirmed this diagnosis, explaining the iron overload, jaundice and evidence of haemolysis. CDA II is a rare genetic disorder characterised by haemolysis, ineffective erythropoiesis and erythroid hyperplasia in bone marrow with numerous bior multinucleated erythroblast. Iron overload may be the main consequence in patients with mild anaemia and haemolysis. In such cases, the combination of iron overload associated with haemolysis must prompt us to look for CDA, including in adult patients.