Enzyme replacement therapy in Fabry's disease

We report a 56-year-old man with history of chronic renal failure, who was diagnosed to have Fabry's disease after performing a percutaneous kidney biopsy. The diagnosis was confirmed by the deficient level of activity of alpha-galactosidase A and by the identification of the mutation. A enzime replacement therapy with alpha-galactosidase A was administered. After 18 months of treatment, a second kidney biopsy was performed showing renal deposits of globotriaosylceramide (we did not evaluate the percentage of histologic clearance of the deposits). Six months after the end of the therapy, a reduction in the impairment of renal function is observed, and the classic manifestations of the disease are absent.     

Fabry disease female proband with clinical manifestations similar to hypertrophic cardiomyopathy

Fabry's disease is an X-linked inborn error of glycosphingolipid catabolism, resulting from a deficiency in alpha-galactosidase A (alpha-Gal A). A 56-year-old Japanese woman was at first suspected of having hypertrophic cardiomyopathy. The patient and her son had alpha-Gal A activity in leukocytes that was remarkably below the limit of controls. DNA analysis of the alpha-Gal A gene revealed a novel missense mutation at codon 19 in exon 1, resulting in leucine-to-proline substitution. As a result she was confirmed as a classic Fabry heterozygote. Recent advances in enzyme replacement therapy can reverse the storage of glycosphingolipids in Fabry's disease. Thus, in patients with cardiac hypertrophy, it is important to differentiate Fabry's disease from other causes of hypertrophy. Therefore, it is necessary to measure alpha-Gal A activity in all suspected cases and to analyze genetic abnormalities in heterozygotes.     

Cardiac abnormalities in Anderson-Fabry disease and Fabry's cardiomyopathy

Fabry's disease is an X-linked lysosomal storage disease most often associated with renal dysfunction and death due to renal failure in patients' fourth and fifth decades of life. However, cardiac manifestations including arrhythmias, angina and heart failure are common and probably underrecognized. Furthermore, Fabry's disease is now recognised as also affecting female carriers, who manifest signs later than males. A variant of Fabry's has been identified that only affects cardiac tissue, which presents as an unexplained hypertrophy of the left ventricle in middle-aged patients, possibly with women more affected than men. Given that epidemiological studies report a prevalence of Fabry's cardiomyopathy among middle-aged patients with cardiac hypertrophy to be anywhere from one to 12%, it is reasonable to screen these patients for alpha-galactosidase A deficiency. Although mortality data is lacking from randomised, controlled trials of galactosidase replacement therapy, there are some reports of improvement in cardiac endpoints. Therefore patients with known Fabry's disease should be screened early for cardiac involvement, as treatment benefit may not be seen once cardiac fibrosis has developed.     

Molecular genetic, biochemical, and clinical studies in three families with cardiac Fabry's disease

The variant form of Fabry's disease, called cardiac Fabry's disease, which has left ventricular hypertrophy as its main clinical manifestation is not uncommon. Because there has been no pedigree analysis in families with cardiac Fabry's disease, we performed gene analyses, enzyme assays, and cardiac evaluations in 3 distinct families with cardiac Fabry's disease. Gene analyses were performed in all 18 members of 3 families including 3 male probands. Five hemizygotes and 6 heterozygotes were identified. Plasma alpha-galactosidase A activity was measured in all 18 family members. Echocardiography and electrocardiography were performed in the 5 hemizygotes and in 5 of the 6 heterozygotes. The proband and 3 heterozygotes from a pedigree with a mutation in exon 6 of the alpha-galactosidase A sequence leading to a Met296Ile substitution showed a decrease in alpha-galactosidase A activity. In a separate pedigree, a proband and his hemizygous brother, with a mutation in exon 2 leading to a Glu66Gln substitution, had a decrease in alpha-galactosidase A activity, whereas 3 heterozygotes had normal values. In the third pedigree, a decrease in alpha-galactosidase A activity was observed in 2 hemizygotes who have a mutation in exon 1 leading to an Ala2OPro substitution. Although all 5 hemizygotes exhibited left ventricular hypertrophy on echocardiography, all 5 heterozygotes lacked this finding. Because plasma alpha-galactosidase A activity was normal in some heterozygotes with cardiac Fabry's disease, gene analysis is essential for an accurate diagnosis. Patients with cardiac Fabry's disease thus show an x-linked form of hypertrophic cardiomyopathy.     

Fabry's disease

Fabry's disease is an X-linked lysosomal storage disorder caused by abnormalities in the GLA gene, which leads to a deficiency in alpha-galactosidase A. The consequent abnormal accumulation of glycosphingolipids results in several clinical signs and symptoms and substantial morbidity and mortality. This review covers all basic aspects of the disease such as epidemiology, pathophysiology, clinical presentation by systems, diagnosis, management, prevention, and repercussions on quality of life. With the development of enzyme replacement therapy in the past few years, early initiation of treatment is key for improvement in major affected organs with decreased cardiac mass and stabilisation of kidney function, and improvement in neuropathic pain, sweating, gastrointestinal symptoms, hearing loss, and pulmonary symptoms. However, treatment of individual symptoms in addition to enzyme replacement therapy seems to be needed for many patients, especially those who have had some degree of organ dysfunction. Additional data are needed to document long-term treatment outcomes.     

Fabry's disease and hypoparathyroidism

INTRODUCTION: Fabry's disease is due to alpha-galactosidase deficiency. This rare lysosomal storage disease is transmitted by recessive X-linked heredity. Sphingolipids (galactosyl-glucosyl-ceramide) accumulate in many organs. CASE REPORT: A 19-year-old man with known hypoparathyroidism presented with telangiectasia and angiokeratomas on the buttocks, the hips, the hands and around the navel. For many years, he suffered from paroxysmal pain in the hands and feet. From childhood, he had complained of diffuse abdominal pain, associated with diarrhea. Ophthalmological slit lamp fundus examination showed corneal telangiectasia and cornea verticella. There was no kidney or heart involvement. The diagnosis of Fabry's disease was confirmed by very low levels of alpha-galactosidase. DISCUSSION: We did not find any other association of hypoparathyroidism and Fabry's disease in the literature. Hypoparathyroidism is not a manifestation of Fabry's disease. Idiopathic hypoparathyroidism is very rare and a genetic origin is known. This disease can be recessive X-linked. A co-transmission of idiopathic hypoparathyroidism and Fabry's disease is probable in our patient.     

Fibroblast alpha-galactosidase A activity for identification of Fabry's disease heterozygotes

The identification of female carriers of Fabry's disease is important for genetic counselling since prenatal diagnosis of affected fetuses is possible. The activities of either total alpha-galactosidase or alpha-galactosidase A in cultured fibroblasts were similar in Fabry carriers and controls and cannot therefore be used for carrier detection. Better discrimination between carriers and controls was found when total alpha-galactosidase activity was expressed as a ratio to beta-galactosidase activity, but overlap still occurred. However, there was complete discrimination between the ratio of alpha-galactosidase A to beta-galactosidase in cultured fibroblasts from five carriers of Fabry's disease and either 11 controls, seven hemizygote affected males or two of their female relatives.     

Avascular necrosis of the femoral head in a patient with Fabry's disease: identification of ceramide trihexoside in the bone by delayed-extraction matrix-assisted laser desorption ionization-time-of-flight mass spectrometry

Fabry's disease is a lipid storage disease caused by an X-linked hereditary deficiency of alpha-galactosidase. The enzymatic defect causes progressive deposition of ceramide trihexoside (CTH) in various tissues, leading to renal failure, premature myocardial infarction, and stroke, with a high rate of mortality in younger patients. Among the complications associated with Fabry's disease, a few cases involving avascular necrosis (AVN) of the femoral head have been reported. However, direct evidence of deposition of CTH in bone marrow in the femoral head has not been demonstrated. This report describes a 58-year-old man who underwent total hip arthroplasty for femoral head AVN associated with Fabry's disease. The accumulation of CTH was examined by chemical analysis of the sphingolipid extracted from the femoral head, using delayed-extraction matrix-assisted laser desorption ionization-time-of-flight mass spectrometry. This is the first report confirming the presence of CTH in the sphingolipid fraction from normal and necrotic bone of a patient with Fabry's disease.     

Biopsy-proven cardiomyopathy in heterozygous Fabry's disease.

A 23-year-old woman with heterozygous Fabry's disease who had acroparesthesia was admitted to hospital for precise examination of the disease before childbearing. She had no cardiac-related symptoms and no abnormality on physical examination. The alpha-galactosidase A activity in her leukocytes was present, but lower than normal. However, the endomyocardial biopsy showed specific changes for Fabry's disease. As Fabry's disease is a rare X-linked recessive inborn error of glycosphingolipid metabolism, heterozygous females are usually asymptomatic, but rarely can be affected as severely as hemizygous males. This is an isolated case of heterozygous Fabry's disease in a female in whom cardiac involvement was detected by endomyocardial biopsy, although she had no cardiac abnormality on physiological examinations. In conclusion, endomyocardial biopsy is useful for evaluation of the cardiac involvement of Fabry's disease even in an asymptomatic case.     

Fabry disease: clinic and enzymatic diagnosis of homozygous and heterozygous. New therapeutic prospects

Fabry disease is an X-linked recessive lysosomal storage disorder caused by a partial or complete deficiency of alpha-galactosidase A. Intracellular accumulation of globotriaosylceramide, the glycolipid substrate of this enzyme, leads to severe painful neuropathy with progressive renal, cardiovascular, and cerebrovascular dysfunction and early death. Men are predominantly affected but many female carriers have similar clinical involvement, including increased risk of stroke. Physical stigmata, such as angiokeratomas in skin and mucous membranes and characteristic benign corneal abnormalities, facilitate identification of Fabry disease. The finding of a marked decreased activity of (alpha-galactosidase A in plasma, white blood cells or cultured skin fibroblasts confirms the diagnosis. Treatment thus far has been symptomatic only. Etiology-based therapies are being developed that include enzyme replacement therapy, gene therapy, and substrate deprivation. The recently completed double-blind, placebo-controlled trials of intravenous infusions of (alpha-galactosidase A in patients with Fabry disease demonstrated the safety and efficacy of this treatment. We report a family with Fabry disease composed of hemicygous and heterocygous. The propositus developed chronic renal failure and received a cadaver renal transplant, which remained with adequate renal function during 15 years.     

Is left ventricular hypertrabeculation/ noncompaction a cardiac manifestation of Fabry's disease?

BACKGROUND AND OBJECTIVES: Some types of hypertrophic cardiomyopathy are due to cardiac Fabry's disease. Since left ventricular hypertrabeculation/noncompaction (LVHT) is regarded a subtype of hypertrophic cardiomyopathy, we looked for the alpha-galactosidase levels in blood leukocytes of LVHT patients. METHODS: Included were male patients in whom LVHT was diagnosed between June 1995 and September 2002. Echocardiographic criteria for LVHT were 1) >3 trabeculations protruding from the left ventricular wall, apically to the papillary muscles, visible in 1 image plane, and 2) intertrabecular spaces perfused from the ventricular cavity, as visualised on colour Doppler imaging. Trabeculations were defined as structures with the same echogenicity as the myocardium and moving synchronously with the ventricular contractions. Excluded were patients with known neuromuscular disorders. All patients were asked for systemic manifestations of Fabry's disease and blood tests were taken. The alpha-galactosidase-A activity was determined by means of an established fluorometric assay in blood leukocytes. RESULTS: Forty-one patients were invited and 26 accepted the invitation. The remaining patients had died (n=5), lived abroad (n=5) or were unwilling (n=5). Among the 26 patients, aged 28-78 years, who followed the invitation, one had renal failure due to renal shrinkage and one had suffered from a stroke 3 years previously. Leukocyte alpha-galactosidase levels ranged from 70 to 188 nM/mg Prot/h (normal: > or =42 nM/mg Prot/h). In none of the patients was the alpha-galactosidase level reduced. CONCLUSION: LVHT does not seem to be a manifestation of cardiac Fabry's disease. To definitively exclude Fabry's disease, however, endomyocardial biopsy is required.     

Cardiac manifestation of Fabry's disease: current knowledge

Fabry's disease is a rare lysosomal storage disease caused by the X-linked defect of the enzyme alpha-galactosidase A leading to the intracellular accumulation of glycosphingolipids in various organs and tissues. Cardiac involvement is frequent and, in individuals with some residual enzyme activity, may be the sole manifestation of the disease. Hemizygous men are generally more seriously affected than heterozygous women. The dominant cardiac manifestations include myocardial hypertrophy of the left ventricle, which, in some patients, mimics hypertrophic cardiomypathy. Left ventricular systolic function is usually preserved, on the other hand mild to moderate diastolic dysfunction is regularly detected. Valvular abnormalities are frequently noted. However, hemodynamically significant lesions are rare. Conduction system involvement leads initially to the shortening of atrioventricular conduction, in later stages, with a progression of the disease, antrioventricular blocks and various forms of supraventricular and ventricular arrhythmias appear. Myocardial ischemia in Fabry disease has in most cases a functional origin due to endothelial dysfunction of coronary arteries and also due to the increase oxygen demand of hypertrophied myocardium. The results of so far performed studies with enzyme replacement therapy are promising in preventing further deterioration and even improving function of affected organs.     

Fabry disease in patients with hypertrophic cardiomyopathy (HCM)

Fabry disease is an X-linked recessive lysosomal storage disorder with variable phenotype characterized by the accumulation of glycosphingolipid in various tissues. Unlike patients with the classical systemic Fabry disease entity, who present with multiple organ involvement, patients with a cardiac variant of Fabry disease are characterized mainly by myocardial hypertrophy. Therefore, the cardiac variant of Fabry disease may be defined as a cardiomyocytic storage disorder, thus, mimicking the clinical features of hypertrophic obstructive and especially non-obstructive cardiomyopathy. In patients with unexplained left ventricular hypertrophy the diagnosis of a cardiac variant of Fabry disease is performed by light- and electron microscopic evaluation of endomyocardial catheter biopsy specimens and/or serologic investigations (decreased activity of alpha-galactosidase A in plasma or leucocytes). Several studies show that between 4% and 8% of unselected patients with the clinical features of hypertrophic non-obstructive cardiomyopathy have a cardiac variant of Fabry disease. In each patient with unexplained myocardial hypertrophy concealed myocardial storage disease, especially cardiac Fabry disease has to be considered and should be ruled out or confirmed by endomyocardial catheter biopsy. This is important because of the recently reported alpha-galactosidase A enzyme replacement therapy in Fabry disease. Randomized, multicenter studies are mandatory to test the hypothesis that enzyme replacement therapy leads to a beneficial clinical effect in the cardiac variant form of Fabry disease and may prevent the progression of the disease in asymptomatic patients.     

Vestibular and cochlear manifestations in Fabry's disease

Anderson-Fabry's disease corresponds to an inherited disorder transmitted by an X-linked recessive gene. The disease is caused by an alpha-galactosidase deficiency leading to an abnormal glycosphingolipid metabolism, resulting in glycosphingolipids deposits all over the body. The disease affects all organs over the body and can be responsible for central nervous system or renal failure, heart attack, which can lead for early death in absence of diagnosis and treatment. In addition to these life-threatening manifestations, other problems which may have a profound impact on quality of life, such as hearing loss, have been relatively neglected. Thus, a large proportion of patients with Fabry's disease suffer from sensorineural hearing loss, with both progressive hearing impairment and sudden deafness, and peripheral vestibular deficits with dizziness and vertigo. The exact pathophysiologic mechanism(s) of those otological complications is still studied, but both cochleo-vestibular disorder and vascular origin seems to be involved. For many years, only symptomatic treatment has been available. For the past ten years, the introduction of enzyme replacement therapy with recombinant agalsidase-α or -β provides new prospect for these patients, decreasing the risk of complications. Still on study, it may also be active both on hearing loss and vestibular disturbances.     

Fifteen-year follow-up of a heterozygous Fabry's disease patient associated with pre-excitation syndrome.

A 47-year-old woman with heterozygous Fabry's disease with pre-excitation syndrome has been followed up for 15 years. Diagnosis was confirmed by the typical electron microscopic feature of the endomyocardial specimen and a decreased plasma alpha-galactosidase activity. As the disease progressed, the interventricular septum thickened from 11 to 17 mm as measured by echocardiography, while the AH interval was prolonged from 80 to 140 msec. In Fabry's disease, the PR interval has been reported to be variable from short PR to AV block. Therefore, this case may be helpful to understand the time course in the AV conduction abnormalities with the progression of Fabry's disease.     

Atrioventricular conduction disturbances in a young patient with Fabry's disease without other signs of cardiac involvement

A 30 year-old male patient with a history of Fabry's disease, was referred to hospital with symptoms of dizziness, hypotension and weakness. Fabry's disease had been diagnosed 2 years before, based on angiokeratoma and hypohidrosis on physical examination and complete lack of alpha-galactosidase A on laboratory examination. The ECG on admission demonstrated sinus bradycardia, with a poor response to atropine administration. Echocardiograms on admission and 2 years before were normal, as well as Holter ambulatory ECG recording. Subsequent electrophysiological study demonstrated mild AV conduction disturbances at a site proximal to His, and the patient was simply advised to be regularly followed up. It can therefore be concluded that even young patients with Fabry's disease and normal echocardiograms might develop cardiac symptoms due to AV conduction abnormalities.     

Fabry's disease.

A 20-year-old man presented with generalized acquired anhidrosis and heat intolerance which was confirmed by a sweat test. Other clinical features included severe pain of the extremities and cutaneous angiokeratomas. On electronmicroscopy, granules specific for Fabry's disease were observed in the endothelial cells. Biochemical examination revealed a decreased level of serum alpha-galactosidase A. These findings confirmed the diagnosis of Fabry's disease.     

Genomic abnormalities of the murine model of Fabry disease after disease-related perturbation, a systems biology approach

Fabry disease is a disorder of alpha-D-galactosyl-containing glycolipids resulting from a deficiency of alpha-galactosidase A. Patients have a poorly understood vascular dysregulation. We hypothesized that disease-related perturbation by using enzyme replacement therapy in the murine model of Fabry disease would provide insight into abnormal biological processes in Fabry disease. Gene expression analyses of the heart, aorta, and liver of male alpha-galactosidase A knockout mice 28 weeks of age were compared with that of WT mice. Microarray analyses were performed before and after six weekly injections of alpha-galactosidase A. Alteration of Rpgrip1 ranked highest statistically in all three organs when knockout mice were compared with WT, and its splice variants responded in a unique way to alpha-galactosidase A. Enzyme replacement therapy tended to not only normalize gene expression, e.g., reduce the overexpression of securin, but also specifically modified gene expression in each tissue examined. Following multiple comparison analysis, gene expression correlation graphs were constructed, and a priori hypotheses were examined by using structural equation modeling. This systems biology approach demonstrated multiple and complex parallel cellular abnormalities in Fabry disease. These abnormalities form the basis for informed, in a Bayesian sense, sequential, hypothesis-driven research that can be subsequently tested experimentally.     

Fabry's disease--late diagnosis in men with chronic nephropathy and skin changes

We report a case of Fabry's disease, diagnosed in a 39-year-old patient treated for 4 years because of glomerulonephritis. The disease manifested itself by the presence of typical petechiae-like skin lesions in the bathing trunk area (angiokeratoma), eye changes, paresthesia, and--in additional investigations--mild proteinuria, lowered creatinine clearance, along with changes in the central nervous system. A biopsy of the kidney revealed the presence of foamy cells in all glomeruli, and in electron microscopy multilamellar bodies (zebra bodies). The diagnose of the disease was confirmed by a marked decrease in leucocyte alpha-galactosidase activity. An early diagnosis of non-inflammatory character of Fabry's disease allows to avoid an unnecessary immunosuppressive treatment.     

Diagnosis of Fabry disease: usefulness of the clinical investigation

Fabry disease, an X-linked lysosomal storage disorder due to alpha-galactosidase A deficiency, leads to an accumulation of globotriaosylceramide resulting in a multisystemic disorder. The initial manifestations of the disease are not specific, leading to a delayed diagnosis. We report a patient in whom the diagnosis was obtained by family screening and the confrontation of clinical signs. We also present a 4 year follow-up under enzyme replacement therapy (agalsidase β, 1 mg/kg/14 days).