Angiokeratoma corporis diffusum. Some clinical aspects.

Angiokeratoma corporis diffusum is a disorder which has tended to escape the attention of paediatricians, though the first symptoms and signs usually develop during childhood. Since the original independent descriptions in 1898 by Anderson and by Fabry, it has been recognized as a systemic disease rather than a dermatological curiosity. Recent work by Sweeley and Klionsky (1963, 1966) suggests that there is a defect in glycolipid synthesis leading to the accumulation of a previously unidentified substance mainly in the walls of blood vessels and in the kidneys. They showed that the major part of this stored glycolipid was ceramide trihexoside or ceramide dihexoside, perhaps resulting from failure of the normal katabolic process to remove further hexose units. They did not identify the defective enzyme reaction. Histological studies using an electron microscope showed the presence of 'myelin figures', resembling those found in Tay-Sachs' disease (Hashimoto, Gross, and Lever, 1965; Frost, Tanaka, and Spaeth, 1966). Hashimoto and his colleagues, therefore, suggested that the defect was in the lysosomal enzymes affecting phospholipoprotein metabolism. However, as the storage products are glycolipids, this is unlikely, but the abnormal enzyme may still be in the lysosomes. In 1962, Wise, Wallace, and Jellinek, in reviewing the cases reported up to that time, pointed out as characteristic features the pains in the extremities, the distribution and appearance of the rash, and the ocular abnormalities. Death usually occurred from renal failure. With wider recognition of the disease, it is becoming apparent that there is rather more variation in the clinical picture, not only between families but also in the same family. The present kindred illustrates this variability. In particular, it is now clear that the disorder may