Lipoid proteinosis. A biochemical and ultrastructural investigation of twonew cases

Lipoid proteinosis is a rare autosomal recessive disease characterized by c utaneous and visceral lesions, in which large amounts of amorphous material are constantly found in stroma. Morphological and biochemical studies indi cate abnormal collagen production, but little attention has been paid to th e lipid component of lesions. Microscopic and ultrastructural studies of sk in, with special emphasis on fibroblasts, vessels, nerve endings and eccrin e sweat glands, were conducted in two patients with lipoid proteinosis. Bio chemical studies were undertaken in cultured fibroblasts. Evidence of lysos omal storage in epithelial cells of eccrine sweat glands and in dermal hist iocytes, very similar to that found in some metabolic disorders, particular ly Farber disease, was found in both cases. Our findings suggest that two a lterations might coexist in lipoid proteinosis, one characterized by impair ed normal collagen production and the ether related to a metabolic defect w hich may lead to accumulation of ceramide or more complex lipids.