The authors describe in an 8-year-old girl congenital haemolytic anaemia which was clinically characterized by medium severe anaemia, splenomegaly and hyperbilirubinaemia. Comprehensive haematological examination after ruling out membranous, enzymopathic and autoimmune types of haemolytic anaemia, in 90% erythrocytes Heinz bodies were found. Unstable non-specified haemoglobin was confirmed by heat precipitation. On electrophoresis of haemoglobin on acetate cellulose a drop of HbA1 to 72.2%, an elevated level of HbF (17.0%) and HbA2 (3.6%) as well as pathological haemoglobin probably of type D in 7.2% was found. As the parents and junior brother were in good health it is assumed that in the patient de novo congenital haemolytic anaemia is involved on the basis of unstable haemoglobin. By splenectomy a satisfactory clinical effect was achieved - improvement of anaemia, hyperbilirubinaemia. The further couse of the disease was complicated 2.5 years after splenectomy by a febrile infection with anaemisation. Etiologically parvovirus B19 was involved. The child is followed up on a long-term basis and during the subsequent 5 years no serious complications developed and the child develops adequately. During repeated examinations laboratory characteristics persist (unstable non-specific pathological haemoglobin).

        Key words: congenital haemolytic anaemia, Heinz bodies, electrophoresis of haemoglobin, unstable haemoglobin, splenectomy, parvovirus B19