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Fabry's disease is a genetic disorder of X-linked inheritance caused by mutations in the alpha galactosidase A gene resulting in deficiency of this lysosomal enzyme. The progressive accumulation of glycosphingolipids, caused by the inadequate enzymatic activity, is responsible of organ dysfunction and thus of clinical manifestations. In the presence of a high clinical suspicion, a careful physical examination and specific laboratory tests are required, finally diagnosis of Fabry's disease is confirmed by the demonstration of absence or reduced alpha-galactosidase A enzyme activity in hemizygous men and gene typing in heterozygous females; in fact the performance of enzymatic activity assay alone in women is inconclusive. Measurement of the biomarkers Gb3 and Lyso Gb3 in biological specimens may facilitate diagnosis. Because of its multisystemic involvement Fabry's disease may present a large spectrum of clinical manifestations as acroparesthesias, hypohidrosis, angiokeratomas, signs and symptoms of cardiac, renal, cerebrovascular involvement (renal insufficiency, proteinuria, left ventricular hypertrophy, strokes). Enzyme replacement therapy with recombinant α- galactosidase A is actually the specific therapy for Fabry disease. Early beginning of this treatment has shown beneficial effects in particular in cardiac and renal disease, a less efficacy it has been reported in central nervous system involvement. ERT has shown to be associated to a significant reduction of Gb3 accumulation in several tissues, in particular heart and kidney; moreover it improves pain related quality of life. Next generation lysosomal storage disorder treatment is based on new strategic approaches as stem cell based therapy, pharmacological chaperones, viral gene therapy; concerning Fabry's disease, it has been recently addressed to great interest this last innovative method, that is to say viral gene therapy, for delivering recombination enzyme into main involved tissues; promising results have been reported in animal models. Great efforts have been made and are still required in this field in order to make available a more effective, safer, advantageous therapeutic strategy for patients with Fabry's disease., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Although clinical evidence of major organ damage is typical of adulthood, many of the signs and symptoms of Anderson Fabry Disease (AFD) occur frequently in childhood. The clinical phenotype of AFD in pediatric patients has been described in several studies which show a higher incidence and an earlier onset of symptoms in male patients than in females. These include neurological manifestations (acroparaesthesias, chronic neuropathic pain, hypo-anhidrosis, tinnitus, hearing, loss), gastrointestinal (GI) symptoms (abdominal pain and diarrhea), angiokeratomas, ocular abnormalities (cornea verticillata, tortuous retinal vessels and subcapsular cataracts). Such manifestations may impair quality of life and, because of their unspecific nature, rarely lead to an early diagnosis. In addition, signs of major organ damage (microalbuminuria or proteinuria, urinary hyperfiltration, impaired heart rate variability, left ventricular hypertrophy, stroke) are encountered in children with AFD. Clinical trials of enzyme replacement therapy (ERT) with agalsidase alfa and agalsidase beta have been conducted in children, with clinical and pharmacodinamc effects proved by both enzyme formulations, whereas differences in safety profile and administration were found. Although several studies suggest that ERT should be started before irreversible damage in critical organs have occurred, the issue of when to initiate it has not yet been resolved. More controlled trials must be done in order to demonstrate that an early start of ERT could prevent adult complications and to assess the optimal timing of treatment in children with AFD. This review aims to provide an update of the current understanding for a better approach of pediatric AFD.

Anderson-Fabry disease is an X-linked lysosomal storage disorder caused by a defect in the α-galactosidase A gene, which leads to the deficiency of the hydrolytic enzyme α-galactosidase A. The consequent inability to catabolize glycosphingolipids causes progressive accumulation of globotriaosylceramide in the vascular endothelium throughout the body. Fatalities in the classical phenotype may usually occur as a consequence of cerebral, cardiac or renal disease. Dermatological manifestations are a relevant feature of Fabry disease and include angiokeratomas, telangiectasiae, lymphedema, anhidrosis or hypohidrosis and pseudo-acromegalic facial appearance. The actual causal treatment for Fabry disease is the enzyme replacement therapy. Dermatologists have a key role, since cutaneous manifestations may lead to the diagnosis. This may help an early therapeutic intervention, reducing both morbidity and mortality.

Fabry disease is a multisystemic X-linked lysosomal storage disorder, caused by the partial or complete deficiency of alpha-galactosidase A activity. The storage of glycosphingolipids in the vascular endothelium and in various tissues can lead to a broad spectrum of clinical manifestations. Renal failure, cardiovascular disease, and strokes are the main causes of morbidity and mortality. Gastrointestinal symptoms, although common, are often under-reported in the literature. This review covers the gastroenterological aspects of Fabry disease.

Fabry disease (FD, OMIM 301500) is a rare X-linked lysosomal storage disorder of the glycosphigolipid metabolism caused by total or partial deficiency of the lysosomal enzyme alpha-galactosidase A (α-gal A). Progressive intralysosomal accumulation of neutral glycosphingolipids in a variety of cell types triggers a cascade of pathophysiological events including cellular death, compromised energy metabolism, small vessel injury, K(Ca)3.1 channel dysfunction in endothelial cells, oxidative stress, impaired autophagosome maturation, tissue ischemia and, importantly, development of irreversible cardiac and renal tissue fibrosis, leading to major multisystemic manifestations. Cardiovascular complications of the disease are very frequent and contribute substantially to disease-related morbidity and mortality in men. Cardiovascular involvement is the leading cause of premature death in heterozygous female patients with FD. Left ventricular hypertrophy is the most prominent cardiac manifestation followed by conduction system disease, valve dysfunction, arrhythmias, vessel disease and coronary microvascular dysfunction. The diagnosis of subclinical forms of the disease, before the development of cardiac hypertrophy, using newer techniques (tissue doppler imaging, strain rate and cardiac magnetic resonance) is crucial to the early initation of the treatment. Greatest benefit of the enzyme replacement treatment is achieved when started at an early stage of the disease before extensive fibrosis or other irreversible tissue damage takes place. Fabry disease should be included in the differential diagnosis algorithm of idiopathic hypertrophy. Determination of Alpha-Gal A activity on plasma and peripheral leukocytes in males and genetic testing in females are the diagnostic gold-standards.

Fabry disease is a progressive devastating disease caused by absent or deficient activity of lysosomal enzyme alpha-galactosidase A, with progressive accumulation of globotriaosylceramide (GL-3) within lysosomes in a different cell types. Accumulation of GL-3 and related glycosphingolipids in different cell types may create diverse clinical picture depending on the organ which is dominantly affected. Renal pathology progresses in severity with aging. Globotryaosil ceramide deposits may be found in different cell types within the kidney. Deposition within the glomeruli may be found in endothelial cells, mesangial cells, interstitial cells, with the highest level found within the podocytes. Although Fabry disease is not curable at the moment, availability of enzyme replacement therapy made it possible to treat this group of patients. Two formulations of recombinant human alpha-galactosidase A are present on the market: agalsidase alfa and agalsidase beta. Longer follow-up period is necessary to estimate the impact of ERT on mortality. Patients with end-stage renal disease caused by Fabry disease could be safely treated with enzyme replacement therapy regardless of the method of renal replacement therapy.

Fabry disease is an X chromosome linked disorder caused by the inherited deficiency of lysosomal enzyme α- galactosidase A. The deficiency results in abnormal degradation of certain glycosphingolipids. Although the disease is known for more than hundred years and the underlying molecular basis is getting to be well defined, there are still a lot of unanswered questions regarding the different clinical presentations, available diagnostic procedures and therapeutic interventions. The scope of the article is to review the molecular basis of Fabry disease and summarize the available data about Fabry disease cardiomyopathy, highlight the controversies of current knowledge and evaluate future research directions.

Fabry disease is an X-linked lysosomal storage disorder (LSD) due to deficiency of the enzyme α-galactosidase A (GLA). Absent or reduced enzyme activity leads to impaired catabolism of neutral glycosphingolipids, particularly globotriaosylceramide (Gb3), resulting in intracellular deposition of such lipids. Clinical manifestations in hemizygote males include angiokeratoma, hypohydrosis, acroparesthesia, abdominal pain, proteinuria, renal insufficiency, left ventricular hypertrophy and cerebrovascular accidents. Heterozygote women may present with mild to severe signs and symptoms. Since year 2001, enzyme replacement therapy (ERT) is the only specific treatment for Fabry disease. The beneficial effect of ERT on different organs/systems has been extensively evaluated, and an improvement in renal function, cardiac mass and quality of life has been reported. Different treatment approaches are currently on development. One of them implies the use of the active-site-specific chaperone 1-deoxygalactonojirimycin that acts facilitating folding of mutant GLA in the endoplasmic reticulum and increasing its lysosomal residual activity. Reduction of Gb3 deposits has been shown in lymphoblasts from Fabry patients with missense mutations and transgenic mouse model expressing a missense mutation GLA. Gene therapy has been also developed as a potential option for treatment of Fabry disease. This review will discuss these novel therapeutic options along with their advantages and limitations.

Enzyme replacement therapy has recently been introduced to treat Fabry disease, a rare X-linked lysosomal storage disorder. The disease occurs due to deficient activity of alpha-galactosidase A, leading to progressive accumulation of globotriaosylceramide in multiple organs and tissues. Renal, cardiac and cerebrovascular manifestations of the disease result in premature death in both hemizygous males and heterozygous females. This paper outlines the clinical signs, symptoms and diagnosis of Fabry disease, and the development of the two available enzyme replacement therapies -- agalsidase alfa and agalsidase beta. Agalsidase alfa and agalsidase beta are produced in a human cell line and in Chinese hamster ovary cells, respectively, resulting in products with the same amino acid sequence as the native human enzyme, but with different patterns of glycosylation. Correct post-translational glycosylation is important in terms of the pharmacokinetics, biodistribution, clinical efficacy and tolerability of genetically engineered protein therapeutics. Differences in glycosylation, which may affect immunogenicity and mannose-6-phosphate receptor-mediated cellular internalisation of administered enzyme, possibly account for the differences in dosing, clinical effects and safety profiles reported for agalsidase alfa and agalsidase beta.