[Sea-blue histiocyte syndrome (author's transl)].

The literature published before October, 1977 on the so-called sea-blue histiocyte syndrome is reviewed. This is a new lipid thesaurismosis, and from a morphological point of view it is characterized by the appearance of large histiocytes in the organs of the reticuloendothelial system with numerous intracytoplasmic granules which take on a typical sea-blue or greenish color with Wright's or Giemsa stain. The exact nature of the accumulated substance has not yet been specifically determined, though it appears to be gluco- and/or phosphosphingolipid, essentially sphingomyelin. The specific biochemical alteration responsible for this chronic deposit has not been established, though a partial sphingomyelinase deficiency has been detected. Sea-blue histiocytes have been observed in two different situations, either as an acquired phenomenon or as a primary condition. Of the latter there have been sporadic cases and cases with a definite familial incidence. The clinical manifestations include enlargement of the liver and spleen, neurological symptoms, cirrhosis of the liver, hemorrhagic diathesis and purpura, chronic pneumopathies, eye or cutaneous disturbances, or no symptoms at all. The disease has a benign clinical course, and the prognosis is less favourable when clinical manifestations appear early in life. These cases have a greater tendency to develop neurological alterations. The final definition of the syndrome must await the clear identification of the accumulated material and the altered enzyme or metabolic pathway.