Bệnh Fabry là một lỗi hiếm hoi của sự trao đổi chất mà kết quả trong một thiếu hụt enzyme α-galactosidase hydrolase lysosomal A. được truyền như là một đặc điểm lặn liên kết với X. Gen chịu trách nhiệm mã hóa của α-galactosidase đã được bản địa hoá giữa cánh tay dài của nhiễm sắc thể | 88 Sangueza and Requena Pathology of Vascular Skin Lesions Fig. 13. Angiokeratomas of Fordyce involving the vulva of an elderly woman. Fig. 14. Angiokeratomas of Mibelli in the inner border of the left hand. disorders but there is also an idiopathic form that presents with no other associated anomalies. Among the different diseases associated with angiokeratoma corporis diffusum Fabry s disease is the most common. Fabry s disease is a rare error of the metabolism that results in a deficiency of the lysosomal enzyme hydrolase a-galactosi-dase A. It is transmitted as an X-linked recessive trait. The gene responsible for the coding of a-galactosidase A has been localized to the middle of the long arm of the X chromosome. As an X-linked disease Fabry s disease exclusively affects males females may be asymptomatic carriers and may have corneal dystrophic changes that can be detected by slit-lamp examination 18 19 . As a consequence of the enzymatic defect glycosphingolipids predominantly trihexosylceramide accumulate within the lysosomes of endothelial cells fibroblasts pericytes and smooth muscle fibers of the dermis. There is also an accumulation of this material in other organs including ganglion cells nerves cornea heart and kidney resulting in cardiac renal ocular and neurologic abnormalities 20 . Angiokeratomas of Fabry s disease usually appear shortly before puberty. They are small punctate dark red papules some of them less than 1 mm mainly located in the lower part of abdomen genitalia buttocks and thighs in a bathing-trunk distribution Figs. 15 16 and 17 . A frequent and asymptomatic finding is the so-called cornea verticillata which is a superficial corneal dystrophy. This finding is of diagnostic importance for the detection of mild cases and female carriers. Other cutaneous manifestations include dry skin anhidrosis hyperthermic crises 21 and acroparaesthesiae secondary to capillary changes in the nail matrix 22 . In rare instances patients with Fabry s .
