Red pulp in splenomegaly syndrome: morphometric light and electron microscopy studies.

From a series of consecutively studied spleens, perfusion-fixed and investigated according to a standardized procedure allowing morphometric investigations at the light and electron microscopic levels, 33 spleens causing splenomegaly syndrome (12 lymphoproliferative diseases, 10 hairy cell leukaemia, 11 myeloproliferative diseases) were compared with data in controls and autoimmune haemolytic anaemia and hereditary spherocytosis from previous studies. In splenomegaly syndrome, especially in hairy cell leukaemia and myeloproliferative diseases, less so in lymphoproliferative diseases, there is a disproportionate increase in the volume of pulp cords in the red pulp. Values for erythrocyte volume density are of the same order as splenic erythrocyte concentration determined by scintigraphic kinetic methods. Cases with complicating immunohaemolysis show a rather high proportion of erythrocyte profiles with nearly spheric shape as in autoimmune haemolytic anaemia and hereditary spherocytosis.