Unusual inclusions in hemoglobin H disease post‐splenectomy

The blood film showed multiple abnormalities (top Images). There was severe microcytosis, hypochromia, striking poikilocytosis, and target cells. Post-splenectomy changes were also seen: acanthocytes, Howell–Jolly bodies, and giant platelets. There were red cell fragments, some of which were acanthocytic while others contained Howell–Jolly bodies or Pappenheimer bodies. Of particular interest, however were unusual inclusions that are specific for hemoglobin H disease post-splenectomy. These were round and dense with the staining characteristics of hemoglobin. They appeared to be bound to the red cell membrane. They resembled the α chain inclusions that can be seen in β thalassemia major or intermedia but appeared denser. A hemoglobin H preparation was positive and showed Heinz bodies in approaching a third of cells (lower Image). Red cell inclusions such as these, representing precipitated β globin tetramers, are not often observed in hemoglobin H disease since, with intact splenic function, they are removed by the spleen. Following splenectomy, they are present in peripheral blood erythrocytes in vivo and are readily observed on a standard May–Grünwald–Giemsa stain. Post-splenectomy two types of inclusion can thus be observed in a hemoglobin H preparation: (i) preformed Heinz bodies that are present in vivo and (ii) characteristic “golf-ball” cells resulting from in vitro precipitation of dissolved hemoglobin H. nil.