Schüller-Christian Disease

SCHÜLLER-CHRISTIAN DISEASE (Schüller, Christian) is a disorder of lipoid metabolism. The disease is extremely rare; only about 20 cases have been described in world literature. Schüller-Christian disease is a genotypic disorder (of recessive type) and frequently runs a familial course. It occurs predominantly in childhood (most often from 3 to 5 years of age), but is also observed in adults. The male sex is preferentially affected. The disturbance of lipoid metabolism is manifested by the deposition and accumulation of neutral fats, cholesterol esters, and phosphatides in the cells (predominantly of the reticuloendothelium) of various organs and tissues. The cells engulfing the lipoids increase sharply in volume and acquire a foamy, "xanthomatous" appearance that is extremely characteristic of this disease. Simultaneously, a granulomatous reaction arises around them, and fibrous tissue develops. Such changes are encountered in Schüller-Christian disease preferentially in the bones of the skull. The formation of xanthoma cells and lipoid granulomatosis in the Haversian canals and bone marrow leads to a softening of the cranial bones and the formation of small, and sometimes very large, bizarre-shaped defects therein, which are easily detected by palpation and roentgenologically. This skull lesion is a classic sign of Schüller-Christian disease and is designated by Schüller as "Landkartenschädel" (geographic skull). The accumulation of xanthomatous-granulation masses at the base of the skull, around the pituitary gland, and in the orbit leads to the emergence of two other pathognomonic signs of Schüller-Christian disease: due to compression of the pituitary gland, especially in the infundibulum region, diabetes insipidus arises (sometimes dwarfism, Simmonds' cachexia, acromegaly, dystrophia adiposo-genitalis), while due to the ingrowth of these masses into the orbit, exophthalmos (protrusion of the eyes) develops, most often bilateral. The ingrowth of lipoid-granulomatous tissue is occasionally observed in the sinuses of the ethmoid and sphenoid bones as well. Along with the skull bones, all other skeletal bones are also affected in the aforementioned manner (though not always). Alongside bone lesions, internal organs (liver, spleen, lungs, endocrine organs) and the skin are less constantly and significantly affected. Lesions of the latter are characterized by the appearance of papulopustular eruptions, the basis of which lies in the formation of xanthoma cells in the depths of the skin, principally along the course of blood vessels. The course of the disease is subacute or chronic. Through the development of fibrous tissue in the lipoid-granulomatous foci, the closure of even very large bone defects is sometimes achieved, thanks to which a relative recovery may ensue. Most often, however, a fatal outcome occurs (frequently from intercurrent diseases). Schüller-Christian disease is essentially very close to Niemann-Pick disease (see Niemann-Pick disease) and differs from it mainly only in the site of deposition of the lipoid masses and the character of the latter. While in Niemann-Pick disease the latter are deposited predominantly in the liver and spleen, leading to the clinical sign of spleno-hepatomegaly, in Schüller-Christian disease lipoids accumulate primarily in the skull bones, causing the above-described clinical symptomatology. By the nature of the lesion, Schüller-Christian disease is also closely related to Gaucher's disease (see Gaucher's disease), especially to its osseous form. The main difference between them is that in Schüller-Christian disease cholesterol, phosphatides, and neutral fats are deposited in the tissues, whereas in Gaucher's disease it is cerasin.

E. Herzenberg