Is it a sea-blue histiocyte?

In the “Images in Hematology’’ section of the Journal, And›ç et al. [1] briefly presented sea-blue histiocytes in a 45-year-old woman with type B Niemann-Pick disease [2,3]. I believe the cell photographed by the authors is fairly typical for Niemann-Pick disease with few nuclear remnants and superimposed lymphocytes. In my opinion, it is not typical for sea-blue histiocytes. We have seen sea-blue histiocyte cells, congenital and acquired, on several occasions [4] in bone marrow and the spleen, as well as in liver aspiration biopsies. Although a few granules may be seen rarely in a few sea-blue histiocytes, they are typically blue cells. Ceroid content determination would be helpful in questionable cells.