LETTERER‐SIWE DISEASE WITH LIPID‐CONTAINING VACUOLATED CELLS

A case of Letterer‐Siwe disease of a 1‐year‐2‐month‐old boy, which clinicopathologically satisfied 7 out of the 8 characteristics of the disease by Siwe's criteria, excluding pathologic changes in the bone is reported. The vacuolated histiocytes appeared in the promerating reticuloendothelial cells in this case; the cells were positive by general fat reaction; the fats consisted of cholesterol fats, phospholipids and neutral lipid. Electron microscopy showed the occurrence of lipid droplets with cholesterol crystals and atypical form of Langerhans cell granule. Granulomatous changes were found in the lymph nodes and spleen, and this case was also simllar in part to chronic granulomatous disease; however, celoid and lipofuscin pigments were negative in the proliferating cells. Cytomegalic inclusion disease as a complication was found in the lungs and intestine, and bilirubin stones in the liver.