Reticuloendothelial granuloma; a review with a report of a case of Letterer-Siwe disease.

Granulomatous lesions affecting the reticuloendothelial system produce a group of disorders having certain striking clinical features. The condition known as Hand-Schuller-Christian disease is one of this group, and the well-known SchiillerChristian triad of exophthalmos, diabetes insipidus, and multiple lesions in the skull was for many years considered to be pathognomonic. More recently Otani and Ehrlich (1940) and Lichtenstein and Jaffe (1940) have described a condition which has come to be known as 'eosinophilic granuloma of bone.' Multiple skeletal lesions may be present, but there is, as a rule, little evidence of systemic upset and recovery is the usual outcome. The rarest and most severe condition in this group is that known as Letterer-Siwe disease. It affects infants, frequently within the first six months of life, and invariably proves fatal. Farber (1941) and Green and Farber (1942) have suggested that the underlying pathological changes in eosinophilic granuloma of bone are similar to those in Hand-Schuller-Christian disease and in Letterer-Siwe disease. Jaffe and Lichtenstein (1944) agreed with this concept and believed that the three conditions were ' different clinical expressions of the same basic disorder'. On the other hand, Siwe (1949) is unwilling to be so definite. He admits that they are all diseases of the reticuloendothelial system but does not feel justified in assuming that anything more than a family relationship exists. The following case is an example of the acute form of reticuloendothelial granuloma known as Letterer-Siwe disease.