Original Article Journal of Inborn Errors of Metabolism & Screening 2016, Volume 4: 1–7 Dermatologic Aspects of Fabry Disease ª The Author(s) 2016 DOI: 10.1177/2326409816661353 iem.sagepub.com Paula C. Luna, MD1,2, Paula Boggio, MD2, and Margarita Larralde, MD, PhD1,2 Abstract Isolated angiokeratomas (AKs) are common cutaneous lesions, generally deemed unworthy of further investigation. In contrast, diffuse AKs should alert the physician to a possible diagnosis of Fabry disease (FD). Angiokeratomas often do not appear until adolescence or young adulthood. The number of lesions and the extension over the body increase progressively with time, so that generalization and mucosal involvement are frequent. Although rare, FD remains an important diagnosis to consider in patients with AKs, with or without familial history. Dermatologists must have a high index of suspicion, especially when skin features are associated with other earlier symptoms such as acroparesthesia, hypohidrosis, or heat intolerance. Once the diagnosis is established, prompt screening of family members should be performed. In all cases, a multidisciplinary team is necessary for the long-term follow-up and treatment. Keywords Fabry disease, angiokeratomas, lysosomal storage disorders Introduction Diffuse AKs are characterized by the presence of multiple lesions that affect more than 1 area of the skin. Although any Fabry disease (FD, also known as Anderson-Fabry disease or region of the skin can be affected, lesions usually localize to the angiokeratoma corporis diffusum [ACD]) is a rare X-linked bathing suit area (from the umbilicus to the upper thighs); this disease caused by the partial or complete deficiency of a lyso- phenotype is known as ACD. This type of AKs, previously somal enzyme, a-galactosidase A (a-Gal A), responsible for 1 considered a synonym of FD, has also been described in several the catabolism of neutral sphingolipids. These nonmetabo- 7-11 other lysosomal storage diseases (Table 2) and exceptionally lized substrates accumulate in the lysosomes of different cells in other systemic conditions.12-15 The rare occurrence of the (predominantly in the endothelial cells) along the whole organ- ACD phenotype with no underlying diseases or metabolic ism. It is a multisystemic and progressive disease with a great alterations has also been described. This type is known as clinical heterogenicity, with classical and mild late-onset phe- idiopathic ACD or ‘‘ACD with no known underlying enzyme notypes.2 It is highly penetrant in males, with a variable expres- alteration.’’ The occurrence of cases of idiopathic ACD with a sivity in females. It is a rare disease with calculated incidence familiar trait raises the issue that there might be an unknown of 1:40.000 for the classical variant. The skin harbors 1 cardinal 16-19 underlying genetic disease. symptom: angiokeratomas (AKs). Angiokeratomas in FD are found in a high percentage of patients: 90% of males and 75% of females.20 In hemizygous Dermatologic Manifestation patients, lesions began to appear around the age of 5 to 8 years, although at that age, they usually go unnoticed or Angiokeratoma Corporis Diffusum The term AKs describes a heterogenous group of lesions char- 1 Dermatology Department, Hospital Alema´n, Buenos Aires, Argentina acterized by the presence of vascular hyperkeratotic papules. 2 Dermatology Department, Hospital General de Agudos J. M. Ramos Mejia, They are mainly divided into 2 groups: localized and Buenos Aires, Argentina 1 generalized. Received February 13, 2016, and in revised form April 14, 2016. Accepted for Localized AK includes AKs of Fordyce, AKs of Mibelli, publication May 30, 2016. 3-5 6 solitary AK, naeviforme AK, and AK of the tongue. These Corresponding Author: lesions show a distinct clinical appearance while sharing his- Paula Luna, Avenida Pueyrredo´n 1640, C1118AAT Buenos Aires, Argentina. topathologic findings described in Table 1. Email: [email protected] This article is distributed under the terms of the Creative Commons Attribution 3.0 License (http://www.creativecommons.org/licenses/by/3.0/) which permits any use, reproduction and distribution of the work without further permission provided the original work is attributed as specified on the SAGE and Open Access pages (https://us.sagepub.com/en-us/nam/open-access-at-sage). 2 Journal of Inborn Errors of Metabolism & Screening Table 1. Different Types of Angiokeratomas. Type Age Sex Clinical Aspect Body Site Trigger Hereditary Association Fabry 5 to 12 Both, predominantly Multiple, clustered red to Any part of No Yes, Acroparesthesias, in males black papules, do not the body, X-linked heart and renal blanch with pressure. especially the failure, stroke, Older lesions become bathing trunk cornea warty area verticillata, etc Mibelli 10 to 15 Both, more frequent Few warty, dark red Lateral aspect Cold Yes, AD History of in female papules and dorsa of acrocyanosis and fingers and chilblains toes, hands and feet Fordyce >60 Male, rare female Multiple warty, vascular Scrotum, No No Local venous lesions rarely vulva hypertension Solitary papular 2nd to 4th Both Few dark red warty Any part of the Trauma No No decade papules (2-10 mm) body, mainly in lower extremities Tongue Adults Both Ventral tongue mainly, also Tongue No No Fabry, fucosidosis, dorsum or nonassociated to other diseases Circumscriptum Congenital Both Single dusky purple plaque. Lower legs or No No Bleed easy when (verrucous (rarely Tends to the foot traumatized. hemangioma) may zosteriform Vascular appear configuration malformations, later in Cobb syndrome life) Abbreviation: AD, Atosomal Dominant. misdiagnosed, mostly when they are isolated (Figure 1).21,22 purpura.32 Dermoscopy might be useful to recognize AKs, Lesions usually appear as minute, isolated red to black papules showing a well-limited red to black lesion with grouped vas- that do not blanch with pressure. As disease progresses, they cular lacunae and some hyperkeratosis.33 From a practical tend to group and turn more verrucous. The most characteristic point of view when assessing patients with multiple AKs, the localization is the bathing trunk area (gluteal, genital and peri- umbilicus should always be evaluated for lesions inside the umbilical areas, lower abdomen, and upper part of the thighs; navel, given their presence is highly evocative of FD (Figure 8). Figures 2-4).23-25 Isolated lesions might also be found over the On the other hand, genitals should be completely evaluated chest, hands and feet, axillae, extensor surface of the arms, both in males and females. Lesions over the dorsum of the elbows (Figure 5), and along the spine (suggesting trauma penis (not only over the scrotum) might be a sign that help might act as a trigger in some areas, the Ko¨ebner phenom- differentiate from the most common and benign Fordyce AK. enon).1 There seems not to be a correlation between the sever- In females, vulvar AKs might be easily unnoticed, as they are ity of the disease and the extension of the AKs, the mutation, or usually asymptomatic and most patient’s lesions are quite the amount of residual enzyme.26 subtle. Rare reports of male adults with few lesions, but with Female patients show a great clinical heterogeneity; some suggestive personal or family history, have been previously may show a full-blown disease and AKs mainly in the bathing published,34 raising the need to rule out FD even in patients trunk area, such as male patients, whereas others show few with scattered cutaneous lesions in the correct clinical context. scattered telangiectatic lesions.27 Although the literature Under the light microscope, histopathologic findings are sim- reports a low frequency of vulvar lesions, in our experience, ilar in all AKs, showing numerous dilated and congestive capil- they are not so infrequent but they might usually be subtle and laries with thin walls in the papillary dermis underlying an easily missed (Figures 6 and 7). There are several differential epidermis that shows different degrees of acanthosis and ortho- diagnosis of AKs.28-30 When lesions are few with a highly keratosis.35 Due to technical issues, the recognition of the lyso- verrucous component, they can be misinterpreted as viral somal deposits in these types of biopsies is very difficult. It is warts. Their vascular origin of these lesions may be confused worth mentioning that not all the lesions show hyperkeratosis, with petechiae, cherry angiomas, capillary aneurisms, pyogenic with some biopsies only revealing vascular dilation, more sim- granulomas, eruptive angiomas,31 or even Schonlein-Henoch ilar to cherry angiomas or telangiectasias.36 For these reasons, Luna et al 3 Table 2. Differential diagnosis of Angiokeratoma Corporis Diffusum. Group Name and Gene Enzyme Deficiency Clinical Findings Dermatological Findings Sphingolipidoses Fabry a-Galactosidase A Acroparesthesias, Heart and Angiokeratoma corporis diffusum, renal failure, stroke, and telangiectasias, hypo-anhidrosis, cornea verticillata and lymphoedema GM1, gangliosidosis b-Galactosidase Facial dysmorphism, Angiokeratoma corporis diffusum hematologic signs. mental retardation and organomegaly Glycoproteinoses Aspartylglucosaminuria Aspartylglucosaminidase Coarse facies, macroglosia, Angiokeratoma corporis diffusum, organomegaly, ocular facial angiofibromas, oral findings, and cardiac valves fibromatosis, and involvement leucokeratosis Fucosidosis a-Fucosidase Mental retardation, coarse Angiokeratoma corporis diffusum, facies, growth retardation,