Electron‐Microscopical Study of Bone Marrow Cells in a Case of Chediak‐Higashi‐Steinbrinck Syndrome

Phase‐contrast and electron‐microscope studies of bone marrow cells in a case of Chediak‐Higashi‐Steinbrinck syndrome are presented. Phase‐contrast microscopy shows giant granules in young granulocytes and in dividing cells. The electron‐microscopical findings are generally in agreement with similar studies by other authors. In addition, structures similar to leucocyte giant granules were observed in erythrocytes. The syndrome seems to be associated with a defective membrane stability of cytoplasmic granules and membrane‐bound lysosomes.