Frequency of Fabry disease in male and female haemodialysis patients in Spain

Prevalence of Fabry disease in patients with chronic kidney disease: A systematic review and meta-analysis

Fabry disease (FD) is an X-linked lysosomal storage disease caused by pathogenic variants in the GLA gene. It has a wide range of clinical manifestations, typically related to the specific underlying GLA variant. One of the main features of FD is kidney involvement; therefore, several studies have addressed the prevalence of FD in all types of patients with chronic kidney disease. We performed a systematic review and meta-analysis of screening studies in chronic kidney disease patients, including those on dialysis, had undergone a kidney transplantation, and those who did not receive kidney replacement therapy, and assessed the prevalence of pathogenic variants in these cohorts. Fifty-five studies were included, involving a total of 84,062 individuals. Of these, 251 cases were positive for FD; a third of the reported GLA variants were of a benign phenotype (37.8%), followed by classical phenotype (31.7%), late onset (15.5%), and of uncertain significance (14.7%). The overall prevalence among dialysis patients was 0.10% (CI95%, 0.06-0.15), 0.28% (CI95%, 0.06-0.15) among patients with kidney transplantation, and 0.17% (CI95%, 0.11-0.39) among those without kidney replacement therapy. Although the overall prevalence of FD is low in patients with kidney involvement, screening, especially in patients who have not yet undergone kidney replacement therapy, is important, in order to provide timely and effective treatment interventions, including disease modifying therapies. The prevalence of kidney involvement in females with Fabry Disease is lower but this should not lead to inadequate follow up. Further research is also needed on the impact of genetic variants of uncertain significance to elucidate their role in Fabry disease.

D313Y Variant in Fabry Disease: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVES

There is accumulating evidence in the literature indicating a strong correlation between Fabry disease (FD) phenotypes and specific sequence variations in the Galactosidase Alpha (GLA) gene. Among them, the potential pathogenicity and clinical relevance of D313Y variation in patients with FD remain debated.

METHODS

We performed a systematic review and meta-analysis of studies reporting D313Y as single occurring variant in the GLA gene and sought to evaluate (1) the prevalence of D313Y variation in different populations with or without clinical manifestations of FD, (2) the clinical FD phenotype in D313Y-positive patients, and (3) the proportion of D313Y-positive patients presenting abnormal laboratory findings (alpha-galactosidase-A deficiency or globotriaosylceramide accumulation).

RESULTS

Forty cohorts comprising 211 individuals with D313Y variation among 42,723 participants with available GLA gene-sequencing data were included. Patients highly suspected for FD had a higher prevalence of D313Y variation (4.9%, 95% CI 1.6%-9.9%; I2 = 95.5%) compared with the general population (0%, 95% CI 0%-0.1%; I2 = 1.9%; p = 0.004). The prevalence of D313Y variation was 0.6% (95% CI 0.3%-1%; I2 = 74.1%), 0.4% (95% CI 0.2%-0.7%; I2 = 0%), and 0.3% (95% CI 0.2%-0.4%; I2 = 0%) in patients presenting with neurologic, cardiac, or renal manifestations, respectively. D313Y was associated with a milder, late-onset FD phenotype, as indicated by the mean patient age of 51 years (95% CI 44-59; I2 = 94%) and the evidence of alpha-galactosidase A deficiency and globotriaosylceramide accumulation in 26.7% (95% CI 15.3%-40%; I2 = 34%) and 16.2% (95% CI 8%-26.4%; I2 = 35%) of cases, respectively. D313Y-positive patients displayed predominantly neurologic FD manifestations (58.1%, 95% CI 37.7%-77.1%; I2 = 78%), with central and peripheral nervous system (CNS/PNS) involvement noted in 28.2% (95% CI 15.4%-43.2%; I2 = 51%) and 28.5% (95% CI 17.8%-40.5%; I2 = 61%) of cases, respectively.

DISCUSSION

D313Y variation seems to correlate with an atypical, mild late-onset phenotype with predominantly neurologic FD manifestations. Monitoring for CNS/PNS involvement is thus paramount to identify D313Y-positive patients with latent or early-FD pathology, which may qualify for enzyme-replacement therapy or chaperone treatment.

Screening of Fabry disease in patients with chronic kidney disease in Japan

BACKGROUND

Fabry disease (FD), an X-linked lysosomal storage disorder caused by a deficiency in alfa-galactosidase A (α-Gal A) activity due to mutations in the GLA gene, has a prevalence of 0-1.69% in patients undergoing haemodialysis; however, its prevalence in patients with chronic kidney disease (CKD) Stages 1-5 is unknown.

METHODS

Serum α-Gal A activity analysis and direct sequencing of GLA were used to screen for FD in 2122 male patients with CKD, including 1703 patients with CKD Stage 5D and 419 with CKD Stages 1-5. The correlation between serum α-Gal A activity and confounding factors in patients with CKD Stages 1-5 was evaluated.

RESULTS

FD prevalence rates in patients with CKD Stage 5D and CKD Stages 1-5 were 0.06% (1/1703) and 0.48% (2/419), respectively. A patient with CKD Stage 5D exhibited a novel GLA mutation, p.Met208Arg, whereas two patients with CKD Stages 1-5 had c.370delG and p.Met296Ile. p. Met208Arg caused moderate structural changes in the molecular surface region near the substituted amino acid residue but did not affect the catalytic residues Asp170 and Asp231 in α-Gal A. Serum α-Gal A activity in patients with CKD Stages 1-5 was inversely correlated with age (P < 0.0001) but directly correlated with estimated glomerular filtration rate (P < 0.0001).

CONCLUSIONS

FD prevalence was much higher in male patients with CKD Stages 1-5 than in those with CKD Stage 5D. FD screening in patients with CKD Stages 1-5 may improve patient survival, decreasing the number of patients with CKD Stage 5D.

High-Risk Screening for Fabry Disease: A Nationwide Study in Japan and Literature Review

Fabry disease (FD) is an X-linked inherited disorder caused by mutations in the GLA gene, which encodes the lysosomal enzyme α-galactosidase A (α-Gal A). FD detection in patients at an early stage is essential to achieve sufficient treatment effects, and high-risk screening may be effective. Here, we performed high-risk screening for FD in Japan and showed that peripheral neurological manifestations are important in young patients with FD. Moreover, we reviewed the literature on high-risk screening in patients with renal, cardiac, and central neurological manifestations. Based on the results of this study and review of research abroad, we believe that FD can be detected more effectively by targeting individuals based on age. In recent years, the methods for high-risk screening have been ameliorated, and high-risk screening studies using GLA next-generation sequencing have been conducted. Considering the cost-effectiveness of screening, GLA sequencing should be performed in individuals with reduced α-Gal A activity and females with certain FD manifestations and/or a family history of FD. The findings suggest that family analysis would likely detect FD patients, although GLA sequencing of asymptomatic family members requires adequate genetic counseling.

Screening for Fabry Disease in Young Strokes in the Australian Stroke Clinical Registry (AuSCR)

Introduction: Fabry disease (FD) is an X-linked lysosomal storage disorder characterized by a deficiency or absence of alpha-galactosidase A (α-GAL A) enzyme, where stroke can be a serious complication. The aim of this study is to determine the feasibility of centralized screening for FD, among young stroke adults registered in the national Australian Stroke Clinical Registry (AuSCR).

Methods: The study was conducted in young (age 18 – 55 years) survivors of acute stroke of unknown etiology registered in AuSCR at hospitals in Queensland, Tasmania, New South Wales, and Victoria during 2014 – 2015; and who, at the 3-month outcome assessment, agreed to be re-contacted for future research. Descriptive analyses of case identification from responses and specific enzyme and DNA sequencing analyses were conducted for α-galactosidase A (α-GLA) from dried blood spot (DBS) testing.

Results: Of 326 AuSCR-identified patients invited to participate, 58 (18%) provided consent but six were subsequently unable to provide a blood sample and two later withdrew consent to use their data. Among the remaining 50 participants (median age 53 years [48 – 56 years]; 47% female), 67% had experienced an acute ischemic stroke. All males (n = 27) had an initial screen for α-GLA enzyme activity of whom seven with low enzyme levels had normal secondary α-GLA gene analysis. All females (n = 23) had genetic analysis, with one shown to have a pathogenic c.352C>T p.(Arg118Cys) missense mutation of the α-GLA gene for FD.

Conclusions: These findings provide logistical data for embedding a process of automated central stroke registry screening for an additional case-finding tool in FD.

Is the alpha-galactosidase A variant p.Asp313Tyr (p.D313Y) pathogenic for Fabry disease? A systematic review

The identification of pathogenic GLA variants plays a central role in the establishment of a definite Fabry disease (FD) diagnosis. We aimed to review and interpret the published data on the p.Asp313Tyr (p.D313Y) variant pathogenicity and clinical relevance. We performed a systematic review of peer-reviewed publications and case-reports on individuals and populations harbouring the p.Asp313Tyr variant. Overall, 35 studies were included in this review. We collected data regarding the clinical manifestations, alpha-galactosidase A enzyme activity, levels of the biomarkers globotriaosylceramide (Gb₃ ) and sphingosine-globotriaosylceramide (lyso-Gb₃ ) and histological findings of p.Asp313Tyr carriers. The prevalence of p.Asp313Tyr in populations at risk for FD (kidney, heart, neurologic disorders, or symptomatic populations) was calculated. We found high residual enzyme activity, low frequency of clinical features specific for FD, non-elevated lysoGb₃ /Gb₃ concentrations and lack of intracellular Gb₃ accumulation in biopsies in the p.Asp313Tyr carriers. The prevalence of the variant in populations at risk for FD was comparable to the reported frequency in the general population. A possible higher frequency was only observed in neurologic disorders. p.Asp313Tyr can be classified as neutral or variant of unknown significance. Further investigations will be helpful to clarify a possible association between the variant and manifestations in the brain vessels.

Predictors of Fabry disease in patients with hypertrophic cardiomyopathy: How to guide the diagnostic strategy?

BACKGROUND

Fabry disease (FD) is a treatable cause of hypertrophic cardiomyopathy (HCM). We aimed to determine the independent predictors of FD and to define a clinically useful strategy to discriminate FD among HCM.

METHODS

Multicenter study including 780 patients with the ESC definition of HCM. FD screening was performed by enzymatic assay in males and genetic testing in females. Multivariate regression analysis identified independent predictors of FD in HCM. A discriminant function analysis defined a score based on the weighted combination of these predictors.

RESULTS

FD was found in 37 of 780 patients with HCM (4.7%): 31 with p.F113L mutation due to a founder effect; and 6 with other variants (p.C94S; p.M96V; p.G183V; p.E203X; p.M290I; p.R356Q/p.G360R). FD prevalence in HCM adjusted for the founder effect was 0.9%. Symmetric HCM (OR 3.464, CI95% 1.151-10.430), basal inferolateral late gadolinium enhancement (LGE) (OR 10.677, CI95% 3.633-31.380), bifascicular block (OR 10.909, CI95% 2.377-50.059) and ST-segment depression (OR 4.401, CI95% 1.431-13.533) were independent predictors of FD in HCM. The score ID FABRY-HCM [-0.729 + (2.781xBifascicular block) + (0.590xST depression) + (0.831xSymmetric HCM) + (2.130xbasal inferolateral LGE)] had a negative predictive value of 95.8% for FD, with a cut-off of 1.0, meaning that, in the absence of both bifascicular block and basal inferolateral LGE, FD is a less probable cause of HCM, being more appropriate to perform HCM gene panel than targeted FD screening.

CONCLUSION

FD prevalence in HCM was 0.9%. Bifascicular block and basal inferolateral LGE were the most powerful predictors of FD in HCM. In their absence, HCM gene panel is the most appropriate step in etiological study of HCM.

Genetic Management Algorithm in High-Risk Fabry Disease Cases; Especially in Female Indexes with Mutations

BACKGROUND

Fabry Disease (FD, OMIM#301500) is a progressive, life-threatening, multisystemic, rare lysosomal storage disease. Today, approximately 1000 mutations are recorded in the Human Gene Mutation Database (www.hgmd.org) for GLA. Among the identified mutations, genetic variants of unknown significance (GVUS) and novel mutations cause problems in terms of diagnosis and treatment approach.

METHODS

In our study, 510 high-risk patients were enrolled. 229 out of 510 were Male (45%) (Mean age was 40.8 ±15.0) and 281 of were Female (55%) (Mean age was 39, 7±15.5). The definite diagnosis of the FD was confirmed by GLA gene sequence analysis. GLA mutation was found in 15 cases (3.4%). Family members of the relevant indexes were included in the screening programs according to the X-linked inheritance pattern. And then we conducted family screening on 74 family members of 15 index cases. Of those 74 cases, 39 had mutations (53%). In males, α-GalA activity and in both gender Lyso-Gb3 levels were measured and multisystem evaluation was performed in all cases with the mutation.

RESULTS

We found six different familial mutation types; two of them pathogenic; p.D170N (1), p.P205S (13), one of them GVUS; p.Q330R (1), three of them likely benign; p.D313Y (12), p.S126G (25), c.-30G>A (2) mutations were detected.

CONCLUSION

The purpose of this retrospective study is to approach Fabry disease on a genetic basis and to improve its management and to draw attention to the importance of early diagnosis. We also aimed to evaluate the appropriate algorithms to determine whether the mutation is the FD-causing mutation or not.

Fabry Disease Screening in Patients With Kidney Transplant: A Single-Center Study in Turkey

OBJECTIVES

Fabry disease is a rare X-linked multisystemic lysosomal storage disorder of the glycosphingolipid metabolic pathway. Nephropathy is one of the most important complications of Fabry disease, and patients with classical phenotype are at risk of developing endstage kidney disease. In this study, we investigated the use of screening for Fabry disease in kidney transplant recipients at our center.

MATERIALS AND METHODS

We screened 301 kidney transplant recipients with functioning grafts. Analyses for α-galactosidase A gene mutation were performed in all female and male kidney transplant recipients. We also measured leukocyte α-galactosidase A enzyme activity in patients with identified GLA mutation.

RESULTS

In 301 kidney transplant recipients, mean age was 42.9 ± 12.5 years, and the number of male patients was 180 (60%). Mean time after transplant was 79 ± 56 months, and estimated glomerular filtration rate was 66.8 ± 21 mL/min/1.73 m². One male patient who was diagnosed with Fabry disease before kidney transplant was also evaluated (mutation in the α-galactosidase A gene, c.1093_1101dup [p.Tyr365_lle367dup]). In 2 female patients, p.A143T (c.427G>A) mutation of unknown significance and p.D313Y (c.937G>T) heterozygous mutation were identified; however, leukocyte ?-galactosidase A enzyme activity was normal in these patients (63.7 and 67.3 nmol/h/mg protein). In the patient diagnosed with Fabry disease, family screening revealed 4 additional affected family members.

DISCUSSIONS

Although prevalence was shown to be low in our center (1/301 patients; 0.33%), screening studies in kidney transplant recipients may help to detect new patients before they develop life-threatening complications such as renal involvement.

Founder effect of Fabry disease due to p.F113L mutation: Clinical profile of a late-onset phenotype

BACKGROUND

Knowledge on clinical profiles of late-onset phenotypes of Fabry disease (FD) is essential to better define their natural history. Our study aims to demonstrate a founder effect of FD due to the GLA gene mutation c.337T>C (p.F113L) in the Portuguese region of Guimarães; and to characterize the clinical profile of this late-onset phenotype in a large cohort of genetically related adult patients, living in the same region.

METHODS AND RESULTS

FD screening was performed in 150 adult patients with hypertrophic cardiomyopathy (HCM) and found 25 Fabry patients (16.6%). The p.F113L mutation was found in 21 of them, leading to a genealogy study and haplotype analysis of the p.F113L patients. Genealogy research revealed a 12-generation family tree with a common ancestor to p.F113L patients, suggesting a founder effect that was supported by haplotype findings. Pedigree analysis was performed and 120 consecutive p.F113L patients underwent a predefined diagnostic evaluation of FD multiorgan involvement. This late-onset phenotype was characterized by common and/or potentially severe cardiac manifestations (left ventricular hypertrophy 40.8%, atrial fibrillation 5%, non-sustained ventricular tachycardia 12.5%, atrioventricular block 18.3%, bifascicular block 13.4%). Extracardiac manifestations included albuminuria>30 mg/24 h 36.1%, chronic kidney disease≥G3 7.6%, brain white matter lesions 54.4%, stroke 3.3%, sensorineural deafness 44.5%, cornea verticillata 13.9%. Plasma lyso-GB3 was undetectable in females, regardless of clinical manifestations.

CONCLUSION

A founder effect of FD due to p.F113L mutation was documented by genealogy and genetics in a Portuguese region. In this late-onset phenotype, although cardiac manifestations carry the highest prognostic impact, extracardiac involvement is common.

Unexpectedly High Prevalence of Low Alpha-Galactosidase A Enzyme Activity in Patients with Focal Segmental Glomerulosclerosis

OBJECTIVES

Fabry disease (FD) is a rare disease associated with sphingolipid accumulation. Sphingolipids are components of plasma membranes that are important in podocyte function and accumulate in various glomerular diseases such as focal segmental glomerulosclerosis (FSGS). Both FD and FSGS can cause podocyte damage and are classified as podocytopathies. In this respect, FD and FSGS share the same pathophysiologic pathways. Previous screening studies have shown that a significant proportion of end-stage renal disease (ESRD) patients receiving hemodialysis (HD) have unsuspected FD, and the prevalence of low alpha-galactosidase A (αGLA) enzyme activity in these patients is higher than that in the normal population. We aimed to compare αGLA enzyme activity in patients with biopsy-proven FSGS and ESRD receiving HD.

METHODS

The records of 232 patients [62 FSGS (F/M: 33/29); 170 HD (M/F: 93/79)] were evaluated retrospectively. The screening was performed based on the αGLA enzyme activity on a dried blood spot, with the confirmation of plasma LysoGb3 levels, and the known GLA mutations were tested in patients with low enzyme activities. The two groups were compared using these parameters.

RESULTS

The mean level of αGLA enzyme activity was found to be lower in FSGS patients than in the HD group (2.88±1.2 μmol/L/h versus 3.79±1.9 μmol/L/h, p<0.001). There was no significant relationship between the two groups with regard to the plasma LysoGb3 levels (2.2±1.22 ng/ml versus 1.7±0.66 ng/ml, p: 0.4). In the analysis of GLA mutations, a D313Y mutation [C(937G>T) in exon p] was found in one patient from the FSGS group.

CONCLUSIONS

We found that αGAL activity in patients with FSGS is lower than that in patients undergoing HD. The low enzyme activity in patients with FSGS may be explained by considering the similar pathogenesis of FSGS and FD, which may also lead to sphingolipid deposition and podocyte injury.

Renal globotriaosylceramide deposits for Fabry disease linked to uncertain pathogenicity gene variant c.352C>T/p.Arg118Cys: A family study

Background

Fabry disease (FD) has an extensive phenotypic expression associated with GLA gene variants. The GLA gene variant c.352C>T/p.Arg118Cys was considered with uncertain pathogenicity because of the finding of high residual alpha‐galactosidase A (α‐Gal A) enzyme activity, the absence of Mendelian segregation with an FD phenotype with many individuals remaining asymptomatic at old ages and the lack of globotriaosylceramide (Gb3) deposits in tissues. Gb3 deposits are found in kidneys before the progression to overt microalbuminuria and decreased glomerular filtration.

Methods

We describe a family with c.352C>T/p.Arg118Cys variant and pathognomonic signs of FD renal damage in masculine children.

Results

The proband died of end‐stage renal failure and we analyzed GLA gene in his offspring and found the variant in all daughters and five of seven grandchildren. In patients who we measure plasma and urinary Gb3, α‐Gal A enzyme activity, and plasma globotriaosylsphingosine (Lyso‐Gb3), these were normal or almost normal. A kidney biopsy was performed in two boys and one girl with normal renal function and characteristic signs of FD as enlarged and vacuolated epithelial cells, myelin figures, myelin‐like figures, lamellated structures in podocytes and endothelial cells, were found in boys. These boys received agalsidase beta 1 mg/kg IV infusion every other week to prevent further renal damage.

Conclusion

This is the first report that shows a link between FD renal Gb3 deposits and c.352C>T/p.Arg118Cys variant, supporting pathogenicity of a variant considered until now with uncertain pathogenicity.

Genetic Factors of Cerebral Small Vessel Disease and Their Potential Clinical Outcome

Cerebral small vessel diseases (SVD) have been causally correlated with ischemic strokes, leading to cognitive decline and vascular dementia. Neuroimaging and molecular genetic tests could improve diagnostic accuracy in patients with potential SVD. Several types of monogenic, hereditary cerebral SVD have been identified: cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL), cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), cathepsin A-related arteriopathy with strokes and leukoencephalopathy (CARASAL), hereditary diffuse leukoencephalopathy with spheroids (HDLS), COL4A1/2-related disorders, and Fabry disease. These disorders can be distinguished based on their genetics, pathological and imaging findings, clinical manifestation, and diagnosis. Genetic studies of sporadic cerebral SVD have demonstrated a high degree of heritability, particularly among patients with young-onset stroke. Common genetic variants in monogenic disease may contribute to pathological progress in several cerebral SVD subtypes, revealing distinct genetic mechanisms in different subtype of SVD. Hence, genetic molecular analysis should be used as the final gold standard of diagnosis. The purpose of this review was to summarize the recent discoveries made surrounding the genetics of cerebral SVD and their clinical significance, to provide new insights into the pathogenesis of cerebral SVD, and to highlight the possible convergence of disease mechanisms in monogenic and sporadic cerebral SVD.

Fabry Nephropathy: An Evidence-Based Narrative Review

Fabry disease (FD) is a rare, X-linked disorder caused by mutations in the GLA gene encoding the enzyme α-galactosidase A. Complete or partial deficiency in this enzyme leads to intracellular accumulation of globotriaosylceramide (Gb3) and other glycosphingolipids in many cell types throughout the body, including the kidney. Progressive accumulation of Gb3 in podocytes, endothelial cells, epithelial cells, and tubular cells contribute to the renal symptoms of FD, which manifest as proteinuria and reduced glomerular filtration rate leading to renal insufficiency. A correct diagnosis of FD, although challenging, has considerable implications regarding treatment, management, and counseling. The diagnosis may be confirmed by demonstrating the enzyme deficiency in males and by identifying the specific GLA gene mutation in male and female patients. Treatment with enzyme replacement therapy, as part of the therapeutic strategy to prevent complications of the disease, may be beneficial in stabilizing renal function or slowing its decline, particularly in the early stages of the disease. Emergent treatments for FD include the recently approved chaperone molecule migalastat for patients with amenable mutations. The objective of this report is to provide an updated overview on Fabry nephropathy, with a focus on the most relevant aspects of its epidemiology, diagnosis, pathophysiology, and treatment options.

Fabry Disease: prevalence of affected males and heterozygotes with pathogenic GLA mutations identified by screening renal, cardiac and stroke clinics, 1995-2017

BACKGROUND

Fabry Disease (FD), an X linked lysosomal storage disease due to pathogenic α-galactosidase A (GLA) mutations, results in two major subtypes, the early-onset Type 1 'Classic' and the Type 2 'Later-Onset' phenotypes. To identify previously unrecognised patients, investigators screened cardiac, renal and stroke clinics by enzyme assays. However, some screening studies did not perform confirmatory GLA mutation analyses, and many included recently recognised 'benign/likely-benign' variants, thereby inflating prevalence estimates.

METHODS

Online databases were searched for all FD screening studies in high-risk clinics (1995-2017). Studies reporting GLA mutations were re-analysed for pathogenic mutations, sex and phenotype. Phenotype-specific and sex-specific prevalence rates were determined.

RESULTS

Of 67 studies, 63 that screened 51363patients (33943M and 17420F) and provided GLA mutations were reanalysed for disease-causing mutations. Of reported GLA mutations, benign variants occurred in 47.9% of males and 74.1% of females. The following were the revised prevalence estimates: among 36820 (23954M and 12866F) haemodialysis screenees, 0.21% males and 0.15% females; among 3074 (2031M and 1043F) renal transplant screenees, 0.25% males and no females; among 5491 (4054M and 1437F) cardiac screenees, 0.94% males and 0.90% females; and among 5978 (3904M and 2074F) stroke screenees, 0.13% males and 0.14% females. Among male and female screenees with pathogenic mutations, the type 1 Classic phenotype was predominant (~60%), except more male cardiac patients (75%) had type 2 Later-Onset phenotype.

CONCLUSIONS

Compared with previous findings, reanalysis of 63 studies increased the screenee numbers (~3.4-fold), eliminated 20 benign/likely benign variants, and provided more accurate sex-specific and phenotype-specific prevalence estimates, ranging from ~0.13% of stroke to ~0.9% of cardiac male or female screenees.

Screening for Fabry Disease in Kidney Disease: a Cross-Sectional Study in Males and Females

BACKGROUND/AIMS

Evaluate the prevalence of Fabry disease in men and women with kidney disease; and observe the presence and importance of the main signs and symptoms in patients with kidney disease.

METHODS

A cross-sectional analysis of secondary data from a multicenter project of Clinical and Epidemiological Analysis of Fabry Disease in 854 Dialysis Centers. A total of 36,442 patients underwent the questionnaire and algorithm; of them, 28,284 were discarded for not presenting signs and symptoms of Fabry disease, while the other 8,087 submitted to blood collection and analysis. All participants signed a Free and Informed Consent Form and a questionnaire was applied. The questionnaire data were analyzed using a computerized algorithm. This program/algorithm analyzes and separates patients into: discarded, patients unlikely to have Fabry disease; suspect, patients who submitted to blood collection. The blood of suspect patients was collected on filter paper for enzyme measurement and genetic testing. A descriptive data analysis was performed and the likelihood ratio was determined.

RESULTS

The general prevalence was 0.19% and after use of algorithm was 0.87%. Although more men were screened (59.3%), the prevalence was higher in women (65.1%). The most prevalent signs and symptoms were: heart disease (60.6%), decreased or lack of sweating (42.3%), heat and cold intolerance (28.2%), and pain crises spreading throughout the body (26.8%).

CONCLUSION

The prevalence was higher in women, and the most prevalent symptom was heart diseases.

Fabry disease due to D313Y and novel GLA mutations

OBJECTIVES

Our aim is to report four novel α-gal A gene (GLA) mutations resulting in Fabry disease (FD) and provide evidence of pathogenicity of the D313Y mutation regarding which contradictory data have been presented in the literature.

SETTING AND PARTICIPANTS

Twenty-five family members of nine unrelated patients with definite FD diagnosis, 10 clinically suspected cases and 18 members of their families were included in this polycentric cohort study.

PRIMARY AND SECONDARY OUTCOME MEASURES

Genotyping and measurement of lyso-Gb₃ was performed in all individuals. The α-Gal A activity was measured in all men as well as plasma and urine Gb₃ concentration in selected cases. Optical and electron microscopy was performed in kidney biopsies of selected patients. All the above were evaluated in parallel with the clinical data of the patients.

RESULTS

Fourteen new cases of FD were recognised, four of which were carrying already described GLA mutations. Four novel GLA mutations, namely c.835C>T, c.280T>A, c.924A>C and c.511G>A, resulting in a classic FD phenotype were identified. Moreover, FD was definitely diagnosed in five patients carrying the D313Y mutation. Eight D313Y carriers were presenting signs of FD despite not fulfilling the criteria of the disease, two had no FD signs and two others were apparently healthy.

CONCLUSIONS

Four novel GLA pathogenic mutations are reported and evidence of pathogenicity of the D313Y mutation is provided. It seems that the D313Y mutation is related to a later-onset milder phenotype than the typical phenotype with normal lysoGb₃ concentration. Our study underlines the significance of family member genotyping and newborn screening to avoid misdiagnoses and crucial delays in diagnosis and treatment of the disease.

Genetic Screening of Mutations Associated with Fabry Disease in a Nationwide Cohort of Juvenile Idiopathic Arthritis Patients

Fabry’s disease (FD) is a lysosomal storage disorder associated with an alpha-galactosidase A deficiency. The prevalence of FD among juvenile idiopathic arthritis (JIA) patients with established diagnosis is unknown, but as musculoskeletal pain may be an important complaint at presentation, misdiagnosed cases are anticipated. With this study, we aim to calculate the frequency of FD-associated mutations in a cohort of JIA patients. Children with JIA from a national cohort were selected. Clinical and laboratorial information was recorded in the Portuguese rheumatic diseases register (http://Reuma.pt). Molecular genetic testing to detect GLA gene mutations was performed. After the multiplex polymerase chain reactions technique for DNA amplification, direct sequencing of the complete sequence of GLA gene was completed. From a cohort of 292 patients with JIA (188 females, 104 males), mutations were identified in 5 patients (all female). Four patients had the mutation D313Y, a rare GLA variant, which is associated with low enzymatic levels in plasma, but normal lysosomal levels. One patient presented the missense mutation R118C, which was previously described in Mediterranean patients with FD. This is the first screening of FD mutations in a cohort of JIA patients. No “classic” pathogenic FD mutations were reported. The late-onset FD-associated mutation, R118C, was found in a frequency of 0.34% (1/292).

Screening of Fabry disease in patients with end-stage renal disease of unknown etiology: the first Thailand study

We aimed to explore the prevalence of Fabry disease in Thai patients who were diagnosed with end-stage renal disease (ESRD) of an unknown origin. Venous blood samples were collected from ESRD patients for biochemical and molecular studies. Alpha-galactosidase A (α-GAL A) screening was performed from dried-blood spots using fluorometry. Molecular confirmation was performed using DNA sequencing of the GLA gene. A total of 142 male and female patients were included in this study. Ten patients (7.04%) exhibited a significant decrease in α-GAL A activity. There were no definitive pathogenic mutations observed in the molecular study. However, four patients revealed a novel nucleotide variant at c.1 -10 C>T, which was identified as a benign variant following screening in the normal population. In conclusion, the α-GAL A assay utilizing dried-blood spots revealed a significant false positive rate. There was no definitive Fabry disease confirmed in Thai patients diagnosed with ESRD of unknown etiology.

Exploratory screening for Fabry's disease in young adults with cerebrovascular disorders in northern Sardinia

BACKGROUND

The etiologic determinants of stroke in young adults remain a diagnostic challenge in up to one-fourth of cases. Increasing evidences led to consider Fabry's disease (FD) as a possible cause to check up. We aimed at evaluating the prevalence of unrecognized FD in a cohort of patients with juvenile stroke in northern Sardinia.

METHODS

For this study, we enrolled 178 patients consecutively admitted to our Neurological Ward for ischemic stroke, transient ischemic attack, intracerebral haemorrhage, neuroradiological evidence of silent infarcts, or white matter lesions possibly related to cerebral vasculopathy at brain MRI, and cerebral venous thrombosis. The qualifying events have to occur between 18 and 55 years of age.

RESULTS

We identified two patients with an α-galactosidase A gene variant, with a prevalence of 0.9 %. According to recent diagnostic criteria, one patient, included for the occurrence of multiple white matter lesions at brain MRI, had a diagnosis of definite FD, the other, included for ischemic stroke, had a diagnosis of uncertain FD.

CONCLUSIONS

Our study places in a middle position among studies that found a prevalence of FD up to 4 % and others that did not find any FD patients. Our findings confirm that FD should be considered in the differential diagnosis of patients with juvenile stroke, particularly those with a personal or familial history positive for cerebrovascular events, or evidence of combined cardiologic and/or renal impairment. All types of cerebrovascular disorders should be screened for FD, including patients with white matter lesions possibly related to cerebral vasculopathy at brain MRI.

The Frequencies of Different Inborn Errors of Metabolism in Adult Metabolic Centres: Report from the SSIEM Adult Metabolic Physicians Group

BACKGROUND

There are few centres which specialise in the care of adults with inborn errors of metabolism (IEM). To anticipate facilities and staffing needed at these centres, it is of interest to know the distribution of the different disorders.

METHODS

A survey was distributed through the list-serve of the SSIEM Adult Metabolic Physicians group asking clinicians for number of patients with confirmed diagnoses, types of diagnoses and age at diagnosis.

RESULTS

Twenty-four adult centres responded to our survey with information on 6,692 patients. Of those 6,692 patients, 510 were excluded for diagnoses not within the IEM spectrum (e.g. bone dysplasias, hemochromatosis) or for age less than 16 years, leaving 6,182 patients for final analysis. The most common diseases followed by the adult centres were phenylketonuria (20.6%), mitochondrial disorders (14%) and lysosomal storage disorders (Fabry disease (8.8%), Gaucher disease (4.2%)). Amongst the disorders that can present with acute metabolic decompensation, the urea cycle disorders, specifically ornithine transcarbamylase deficiency, were most common (2.2%), followed by glycogen storage disease type I (1.5%) and maple syrup urine disease (1.1%). Patients were frequently diagnosed as adults, particularly those with mitochondrial disease and lysosomal storage disorders.

CONCLUSIONS

A wide spectrum of IEM are followed at adult centres. Specific knowledge of these disorders is needed to provide optimal care including up-to-date knowledge of treatments and ability to manage acute decompensation.

Prevalence of Fabry disease in dialysis patients: Japan Fabry disease screening study (J-FAST)

BACKGROUND

In Fabry disease, progressive glycolipid accumulation leads to damage in kidney and other organs. This study was designed to determine the prevalence rate of Fabry disease in Japanese dialysis patients.

METHODS

All dialysis patients agreeing to Japan Fabry disease screening study (J-FAST) with informed consent were selected except for Fabry disease. The screening was performed by a method of measuring plasma and/or leukocytes lysosomal α-galactosidase A protein level and α-galactosidase A activity. If positive, genetic analysis was carried out upon patient's agreement.

RESULTS

J-FAST dealt with 8547 patients (male 5408, female 3139). At the tertiary examination, 26 out of 8547 patients were found to be positive. Six out of 26 patients could not accept genetic analysis because of death. Remaining 20 patients agreed with genetic analysis; then 2 patients (male 2, female 0) had a variation of the α-Gal gene and 11 patients showed E66Q variations. Therefore, the frequency of Fabry disease in J-FAST was 0.04 % (2/5408) in males and 0 % (0/3139) in females, and then 0.02 % (2/8547) in all patients. The presumptive clinical diagnoses of end-stage kidney disease (ESKD) were 10 chronic glomerulonephritis, 7 diabetic nephropathy, 3 unknown etiology, 3 nephrosclerosis, 1 gouty nephropathy, 1 autosomal dominant polycystic kidney disease and 1 renal tuberculosis among 26 tertiary positive patients. Two male Fabry patients were initially diagnosed as nephrosclerosis and chronic glomerulonephritis.

CONCLUSIONS

The prevalence rate of Fabry disease in J-FAST was 0.02 %. Moreover, Fabry disease could not be ruled out as the clinical diagnosis of ESKD.

The alpha-galactosidase A p.Arg118Cys variant does not cause a Fabry disease phenotype: data from individual patients and family studies

Lysosomal α-galactosidase A (α-Gal) is the enzyme deficient in Fabry disease (FD), an X-linked glycosphingolipidosis caused by pathogenic mutations affecting the GLA gene. The early-onset, multi-systemic FD classical phenotype is associated with absent or severe enzyme deficiency, as measured by in vitro assays, but patients with higher levels of residual α-Gal activity may have later-onset, more organ-restricted clinical presentations. A change in the codon 118 of the wild-type α-Gal sequence, replacing basic arginine by a potentially sulfhydryl-binding cysteine residue - GLA p.(Arg118Cys) -, has been recurrently described in large FD screening studies of high-risk patients. Although the Cys118 allele is associated with high residual α-Gal activity in vitro, it has been classified as a pathogenic mutation, mainly on the basis of theoretical arguments about the chemistry of the cysteine residue. However its pathogenicity has never been convincingly demonstrated by pathology criteria. We reviewed the clinical, biochemical and histopathology data obtained from 22 individuals of Portuguese and Spanish ancestry carrying the Cys118 allele, including 3 homozygous females. Cases were identified either on the differential diagnosis of possible FD manifestations and on case-finding studies (n=11; 4 males), or on unbiased cascade screening of probands' close relatives (n=11; 3 males). Overall, those data strongly suggest that the GLA p.(Arg118Cys) variant does not segregate with FD clinical phenotypes in a Mendelian fashion, but might be a modulator of the multifactorial risk of cerebrovascular disease. The Cys118 allelic frequency in healthy Portuguese adults (n=696) has been estimated as 0.001, therefore not qualifying for "rare" condition.

Idiopathic small fiber neuropathy: phenotype, etiologies, and the search for fabry disease

Background and Purpose

The etiology of small fiber neuropathy (SFN) often remains unclear. Since SFN may be the only symptom of late-onset Fabry disease, it may be underdiagnosed in patients with idiopathic polyneuropathy. We aimed to uncover the etiological causes of seemingly idiopathic SFN by applying a focused investigatory procedure, to describe the clinical phenotype of true idiopathic SFN, and to elucidate the possible prevalence of late-onset Fabry disease in these patients.

Methods

Forty-seven adults younger than 60 years with seemingly idiopathic pure or predominantly small fiber sensory neuropathy underwent a standardized focused etiological and clinical investigation. The patients deemed to have true idiopathic SFN underwent genetic analysis of the alpha-galactosidase A gene (GLA) that encodes the enzyme alpha-galactosidase A (Fabry disease).

Results

The following etiologies were identified in 12 patients: impaired glucose tolerance (58.3%), diabetes mellitus (16.6%), alcohol abuse (8.3%), mitochondrial disease (8.3%), and hereditary neuropathy (8.3%). Genetic alterations of unknown clinical significance in GLA were detected in 6 of the 29 patients with true idiopathic SFN, but this rate did not differ significantly from that in healthy controls (n=203). None of the patients with genetic alterations in GLA had significant biochemical abnormalities simultaneously in blood, urine, and skin tissue.

Conclusions

A focused investigation may aid in uncovering further etiological factors in patients with seemingly idiopathic SFN, such as impaired glucose tolerance. However, idiopathic SFN in young to middle-aged Swedish patients does not seem to be due to late-onset Fabry disease.

Fabry disease presenting as apical left ventricular hypertrophy in a patient carrying the missense mutation R118C

Anderson-Fabry disease is an X-linked lysosomal storage disorder caused by abnormalities of the GLA gene, which encodes the enzyme α-galactosidase A. A deficiency of this enzyme leads to the lysosomal accumulation of glycosphingolipids, which may cause left ventricular hypertrophy that is typically concentric and symmetric. We present the case of a 60-year-old woman with symptoms of dyspnea, atypical chest pain and palpitations, in whom a transthoracic echocardiogram revealed an apical variant of hypertrophic cardiomyopathy. Analysis of specific sarcomeric genetic mutations was negative. The patient underwent a screening protocol for Anderson-Fabry disease, using a dried blood spot test, which was standard at our institution for patients with left ventricular hypertrophy. The enzymatic activity assay revealed reduced α-galactosidase A enzymatic activity. Molecular analysis identified a missense point mutation in the GLA gene (p.R118C). This case report shows that Anderson-Fabry disease may cause an apical form of left ventricular hypertrophy. The diagnosis was only achieved because of systematic screening, which highlights the importance of screening for Anderson-Fabry disease in patients with unexplained left ventricular hypertrophy, including those presenting with more unusual patterns, such as apical variants of left ventricular hypertrophy. This case also supports the idea that the missense mutation R118C is indeed a true pathogenic mutation of Anderson-Fabry disease.

Difficulties and barriers in diagnosing Fabry disease: what can be learnt from the literature?

INTRODUCTION

Fabry disease (FD) is an X-linked disorder of glycosphingolipid metabolism caused by deficiency of the lysosomal enzyme alpha galactosidase A. Clinical features include neuropathic pain, rash, proteinuria renal failure, stroke and cardiomyopathy accompanied by a reduced life expectancy. Patients report an average delay of > 10 years between symptom onset and diagnosis. Newborn screening studies suggest a much higher prevalence than that found on population studies supporting the notion that FD is under-diagnosed.

AREAS COVERED

Four key challenges in the diagnosis of FD and strategies to overcome them are discussed. The clinical features of FD are highly heterogeneous resulting in patients presenting to many different specialists, often with non-specific symptoms with a wide differential diagnosis. The pathophysiological mechanisms underlying this are poorly understood and the prediction of pathogenicity on the basis of gene mutation analysis can be problematic. While the availability of treatment adds an impetus to make the correct diagnosis, our understanding of when and if treatment may be required in a specific individual is incomplete.

EXPERT OPINION

Improving diagnostic rates of FD requires a greater awareness of the disorder among physicians to whom patients may present, new strategies to determine the pathogenicity of novel mutations and a greater understanding of the natural history of FD across the phenotypic spectrum. Collaborative clinical and laboratory research is vital in furthering knowledge of the underlying mechanisms of this disorder and how they may be impacted by current or future therapies.

Screening for Fabry disease in patients undergoing dialysis for chronic renal failure in Turkey: identification of new case with novel mutation

BACKGROUND

Chronic renal failure (CRF) is a serious complication of Fabry disease (FD). The aims of the present study were to determine the prevalence of unrecognized FD in Turkish hemodialysis population and to investigate the molecular background.

METHOD

Primarily, α-galactosidase A (α-Gal A) activity was investigated on DBS in 1136 patients of both sexes who underwent dialysis for CRF in Turkey. The disease was confirmed by analyzing enzyme activity in leukocyte and GLA gene sequencing in all patients in whom α-Gal A level was 40% of normal or less.

RESULTS

Mean age of the patients (44.5% female, 52.5% male) was 56.46±15.85 years. Enzyme activity was found low with DBS method in 12 patients (four males, eight females). Two men, but no women, were diagnosed with FD by enzymatic and molecular analysis. In consequence of genetic analysis of a case, a new mutation [hemizygote c.638C>T (p.P214S) missense mutation in exon 5] was identified, which was not described in literature. Family screening of cases identified six additional cases.

CONCLUSION

As a result of this initial screening study performed on hemodialysis patients for the first time with DBS method in Turkey, the prevalence of FD was detected as 0.17%. Although the prevalence seems to be low, screening studies are of great importance for detecting hidden cases as well as for identifying other effected family members.

Multifocal white matter lesions associated with the D313Y mutation of the α-galactosidase A gene

White matter lesions (WML) are clinically relevant since they are associated with strokes, cognitive decline, depression, or epilepsy, but the underlying etiology in young adults without classical risk factors still remains elusive. Our aim was to elucidate the possible clinical diagnosis and mechanisms leading to WML in patients carrying the D313Y mutation in the α-galactosidase A (GLA) gene, a mutation that was formerly described as nonpathogenic. Pathogenic GLA mutations cause Fabry disease, a vascular endothelial glycosphingolipid storage disease typically presenting with a symptom complex of renal, cardiac, and cerebrovascular manifestations. We performed in-depths clinical, biochemical and genetic examinations as well as advanced magnetic resonance imaging analyses in a pedigree with the genetically determined GLA mutation D313Y. We detected exclusive neurologic manifestations of the central nervous system of the “pseudo”-deficient D313Y mutation leading to manifest WML in 7 affected adult family members. Furthermore, two family members that do not carry the mutation showed no WML. The D313Y mutation resulted in a normal GLA enzyme activity in leukocytes and severely decreased activities in plasma. In conclusion, our results provide evidence that GLA D313Y is potentially involved in neural damage with significant WML, demonstrating the necessity of evaluating patients carrying D313Y more thoroughly. D313Y might broaden the spectrum of hereditary small artery diseases of the brain, which preferably occur in young adults without classical risk factors. In view of the existing causal therapy regime, D313Y should be more specifically taken into account in these patients.

Screening of male dialysis patients for fabry disease by plasma globotriaosylsphingosine

BACKGROUND AND OBJECTIVES

Previous reports of Fabry disease screening in dialysis patients indicate that α-galactosidase A activity alone cannot specifically and reliably identify appropriate candidates for genetic testing; a marker for secondary screening is required. Elevated plasma globotriaosylsphingosine is reported to be a hallmark of classic Fabry disease. The purpose of this study was to examine the usefulness of globotriaosylsphingosine as a secondary screening target for Fabry disease.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This study screened 1453 patients, comprising 50% of the male dialysis patients in Niigata Prefecture between July 1, 2010 and July 31, 2011. Screening for Fabry disease was performed by measuring the plasma α-galactosidase A enzyme activity and the globotriaosylsphingosine concentration, by high-performance liquid chromatography. Genetic testing and genetic counseling were provided.

RESULTS

A low level of plasma α-galactosidase A activity (≤4.0 nmol/h per milliliter) was observed in 47 patients (3.2%). Of these, 3 (0.2%) had detectable globotriaosylsphingosine levels. These patients all had α-galactosidase A gene mutations: one was p.Y173X and two were the nonpathogenic p.E66Q. The patient with p.Y173X started enzyme replacement therapy. Subsequent screening of his family identified the same mutation in his elder sister and her children. Genetic testing for 33 of the other 44 patients detected 7 patients with p.E66Q. Thus, the plasma lyso-Gb3 screen identified Fabry disease with high sensitivity (100%) and specificity (94.3%).

CONCLUSIONS

Plasma globotriaosylsphingosine is a promising secondary screening target that was effective for selecting candidates for genetic counseling and testing and for uncovering unrecognized Fabry disease cases.

No accumulation of globotriaosylceramide in the heart of a patient with the E66Q mutation in the α-galactosidase A gene

BACKGROUND

Fabry disease is an X-linked lysosomal disorder resulting from mutations in the α-galactosidase A (GLA) gene. Recent reports described that the E66Q mutation of GLA is not a disease-causing mutation. However, no pathological study was reported. We carried out pathological studies using a cardiac biopsy specimen from a patient with the E66Q mutation.

MATERIALS AND METHODS

The case was a 34 year old male patient with end-stage renal failure and cardiomegaly. He was diagnosed with gout at 15 years of age and hemodialysis was started for gouty nephropathy from 31 years of age. He was suspected of having Fabry disease as the result of a screening study for Fabry disease in patients with end-stage renal failure and was referred to our hospital for mutation analysis of the GLA gene. We carried out enzymatic and genetic analysis for GLA and pathological studies of a cardiac biopsy specimen.

RESULTS

The patient had the E66Q mutation in the GLA gene. GLA activity in leukocytes was 36.2% of the average of normal controls. The pathological study of the cardiac biopsy sample showed no characteristic findings of Fabry disease. The immunohistochemistry for GL3 of the cardiac biopsy sample showed no positive cells.

CONCLUSION

Although the E66Q mutation reduced enzyme activity, the characteristic pathological findings of Fabry disease and the abnormal accumulation of GL3 were not detected in cardiac tissues. The E66Q mutation of the GLA gene is thought to be a functional polymorphism based on enzymatic and pathological studies.

Descriptive epidemiology of Fabry disease among beneficiaries of the Specified Disease Treatment Research Program in Japan

Background

Fabry disease (FD) is a rare X-linked lysosomal storage disorder and is included in the Specified Disease Treatment Research Program in Japan, which subsidizes medical care for beneficiaries with rare and other, designated diseases. However, no report on the epidemiologic features of Fabry disease has been published in Japan.

Methods

We used clinical research data reports submitted to the program between 2003 and 2008 to assess the epidemiologic features of 315 beneficiaries with FD.

Results

Of the 315 program beneficiaries, 198 were men (mean age, 37.4 years) and 117 were women (mean age, 51.2 years). The overall incidence in Japan was 0.25 cases per 100 000 individuals, and prevalence among men was 1.78 times that among women. More than 80% of beneficiaries were capable of working, going to school, or doing housework; however, 46 beneficiaries (14.6%) required home care, and 9 (2.9%) were living in hospitals or other medical facilities. As compared with the previous year, the clinical course of FD at beneficiary registration was unchanged for 178 of 290 beneficiaries (61.4%), worse for 81 (27.9%), and improved or cured for 31 (10.7%). The distribution of beneficiary-related characteristics was similar between men and women, and no significant difference was observed.

Conclusions

The high percentage (>80%) of individuals with FD who were able to work, attend school, and perform tasks such as housework could reflect an improvement in the clinical course of FD after enzyme replacement therapy. We must continue data collection and conduct further studies to improve our understanding of the descriptive epidemiology of FD.

Lyso-Gb3 Indicates that the Alpha-Galactosidase A Mutation D313Y is not Clinically Relevant for Fabry Disease

The X-chromosomal-linked lysosomal storage disorder Fabry disease can lead to life-threatening manifestations. The pathological significance of the Fabry mutation D313Y is doubted, because, in general, D313Y patients do not present clinical manifestations conformable with Fabry disease. This is in contrast to the analysis of the alpha-galactosidase A activity, which is reduced in D313Y patients. We report a comprehensive clinical, biochemical and molecular genetic analysis of two patients with a D313Y mutation. The alpha-galactosidase A activity was reduced in both patients. No Fabry symptoms or Fabry organ involvement was detected in these patients. The new biomarker lyso-Gb3, severely increased in classical Fabry patients, was determined and in both patients lyso-Gb3 was below the average of a normal population.Our data for the first time not only clinically but also biochemically supports the hypothesis that the D313Y mutation is not a classical one, but a rare variant mutation.

A distinct urinary biomarker pattern characteristic of female Fabry patients that mirrors response to enzyme replacement therapy

Female patients affected by Fabry disease, an X-linked lysosomal storage disorder, exhibit a wide spectrum of symptoms, which renders diagnosis, and treatment decisions challenging. No diagnostic test, other than sequencing of the alpha-galactosidase A gene, is available and no biomarker has been proven useful to screen for the disease, predict disease course and monitor response to enzyme replacement therapy. Here, we used urine proteomic analysis based on capillary electrophoresis coupled to mass spectrometry and identified a biomarker profile in adult female Fabry patients. Urine samples were taken from 35 treatment-naïve female Fabry patients and were compared to 89 age-matched healthy controls. We found a diagnostic biomarker pattern that exhibited 88.2% sensitivity and 97.8% specificity when tested in an independent validation cohort consisting of 17 treatment-naïve Fabry patients and 45 controls. The model remained highly specific when applied to additional control patients with a variety of other renal, metabolic and cardiovascular diseases. Several of the 64 identified diagnostic biomarkers showed correlations with measures of disease severity. Notably, most biomarkers responded to enzyme replacement therapy, and 8 of 11 treated patients scored negative for Fabry disease in the diagnostic model. In conclusion, we defined a urinary biomarker model that seems to be of diagnostic use for Fabry disease in female patients and may be used to monitor response to enzyme replacement therapy.