Acquired haemoglobin H disease, complicating a myeloproliferative syndrome: a case report

A case of acquired haemoglobin H disease in association with a myeloproliferative disorder is described. Severe haemolysis with hypochromic microcytic anaemia was present. Haemoglobin H formed 18% of the circulating haemoglobin and 60% of the red cells showed multiple inclusions on incubation with brilliant cresyl blue. Blood film and absolute red cell values from a previous unrelated illness were normal, proving the acquired nature of the haemoglobin abnormality. Alpha/beta chain synthesis was measured in vitro and the degree of imbalance (alpha/beta ratio 0.39) was similar to that seen in the inborn thalassaemic disorder. A small proportion of red cells showed i-antigen reactivity but their haemoglobin H content was no different from the majority of cells which were l-antigen positive.