Systemic non-Langerhans cell histiocytic disorder characterized by the abnormal accumulation of histiocytes (macrophages) most often called the non-Langerhans-cell histiocytosis. This leads to the development of lipoid granulomas in many organs and tissues of the body, especially the bone marrow, leading to generalized sclerosis of the long bones. The onset of the disease is the middle age. The clinical features also include in more than 50% of affected individuals cases extraskeletal involvement such as kidney, skin, brain, and lung disease, and less frequently retroorbital tissue, pituitary gland, and heart. The clinical manifestations range from asymptomatic to fatal multisystem derangement.
Lipid Granulomatosis Syndrome; Erdheim-Chester Syndrome; Polyostotic Sclerosing Histiocytosis.
This medical condition was first described by the American pathologist William Chester in 1930 during his visit to the Jakob Erdheim, an Austrian pathologist, in Vienna. Credit was later given to Erdheim even though he was not an author on the paper.
Approximately 500 cases have been reported in the literature to date. Erdheim-Chester disease (ECD) has a male predilection and most often affects adults older than 40 years. The median age is established at 53 years. This disorder has a high mortality rates. In 2005, the survival rate was less than 50% within 3 years from diagnosis. However, with interferon therapy the 5-year survival rate is estimated at 68%.
Etiology is unknown. No genetic basis has been described.
ECD results from infiltration of the bones and other tissues by foamy histiocytes. These histiocytes are derived from monocytes/macrophages, lack intracytoplasmic granules (Birbeck granules), and do not stain positive for S-100 protein, which makes them histologically distinguishable from histiocytes derived from Langerhans cells. (However, researchers now have found extensive S-100–positive staining in some ECD histiocytes, so further evaluation seems necessary.) ECD characteristically affects the long bones symmetrically.
Based on clinical and histopathologic findings. Symmetrical long bone osteosclerosis is the characteristic radiologic finding. However, histologic confirmation is required for the final diagnosis, preferentially from specimens from bone or retrobulbar tissue.
ECD is a systemic, xanthogranulomatous, proliferative, infiltrative disease with foamy (lipid-laden) macrophages/histiocytes of unknown etiology. The signs and symptoms are unspecific and mainly result from the histiocytic infiltration of different tissues. The bones most often affected are the femora, tibiae, and fibulae; humeri, ulnae, and radius are less often involved. The axial skeleton is usually spared. The diaphyses and metaphyses of the long bones are characterized by a diffuse or patchy increase in density, coarsening of the trabecular pattern, medullary sclerosis, and cortical thickening. The epiphyses usually are not affected. The most common presenting features include lower limb pain (knees, ankles), exophthalmos, diabetes insipidus, and general symptoms such ...