Recommendations for initiation and cessation of enzyme replacement therapy in patients with Fabry disease: the European Fabry Working Group consensus document

Expanded screening for Fabry disease in patients with chronic kidney disease not on dialysis: a multicenter Italian experience

Fabry disease (FD) is a progressive, multisystemic X-linked disorder caused by mutations in the GLA gene, often leading to renal failure. Although several screening programs have been conducted, the prevalence of FD in patients with chronic kidney patients who are not dependent on dialysis (NDD-CKD) is likely underestimated due to restrictive inclusion criteria and methodological shortcomings. This study aims to assess the prevalence of FD in NDD-CKD patients using an expanded screening approach. Ongoing outpatients attending Italian nephrology clinics were screened by assay of plasma α-galactosidase A (α-Gal A) activity. Genetic testing was also performed in all females and males with low α-Gal A activity. Inclusion criteria were: (1) females ≥18 years old; (2) males aged between 18 and 70 years; (3) NDD-CKD stages 1-5. Patients with histological diagnosis of glomerulonephritis or diagnosis of autosomal dominant polycystic kidney disease (ADPKD) were excluded. Demographic data and laboratory results were also collected. Among 385 NDD-CKD outpatients, 173 underwent screening. One patient with three family members carrying a novel mutation (c.320 A > G, p.Q107R); one patient with three family members carrying a silent mutation (c.48 T > G, p.L16L) and two patients with a missense mutation (c.376A > G, p.S126G), were identified. Overall, the prevalence of FD was 2.3%, increasing to 5.4% (10 in 183) with family screening. FD may be more common than previously believed, particularly within NDD-CKD populations. FD screening should be expanded to include NDD-CKD patients with known causes of CKD, such as hypertension and diabetes mellitus, and genetic testing should be routinely used for female patients.

Cost-effectiveness analysis of enzyme replacement therapy for the treatment of Chinese patients with fabry disease: a Markov model

Background

Fabry disease (FD) is an X-chromosome-linked genetic disorder. Currently, the main treatments for FD include disease-nonspecific and disease-specific treatments. Nonspecific treatment involves symptomatic management of organ involvement. On the other hand, disease-specific treatment is to regulate the activity of the corresponding enzymes, which is targeted. Among them, enzyme replacement therapy (ERT) is a classical therapy. Several studies have demonstrated the significant ameliorative effect of agalactosidase-α (ALTA-a) on cardiac and renal function in patients with FD. Despite the excellent clinical performance, there are limited pharmacoeconomic studies on ERT for FD worldwide.

Objective

The aim of this study was to analyze the cost-effectiveness of ERT for FD in China from the perspective of the healthcare system.

Methods

We constructed a five-state Markov model based on the disease characteristics of FD. The modeling period was 1 month. The time horizon was 3 years. The willingness-to-pay threshold was chosen as 1-3 times the gross national product (GDP) per capita. The incremental cost-effectiveness ratio (ICER) was calculated from the base case analysis, and one-way sensitivity analysis and probabilistic sensitivity analysis were performed.

Results

The ICER value is ¥148071.95/QALY, which is between 1-3 times GDP per capita. The sensitivity analysis showed that the cost of ALTA-a had a significant effect on ICER and proved the stability of the results.

Conclusion

ERT therapy is a cost-effective program compared to "No ERT" therapy.

Fabry Disease: Insights into Pathophysiology and Novel Therapeutic Strategies

Fabry disease (FD) is an X-linked lysosomal storage disorder characterized by deficiency of α-galactosidase A (α-GalA), leading to the accumulation of glycosphingolipids and multi-organ dysfunction, particularly affecting the cardiovascular and renal systems. Disease-modifying treatments such as enzyme replacement therapy (ERT) and oral chaperone therapy (OCT) have limited efficacy, particularly in advanced disease, prompting a need for innovative therapeutic approaches targeting underlying molecular mechanisms beyond glycosphingolipid storage alone. Recent insights into the pathophysiology of FD highlights chronic inflammation and mitochondrial, lysosomal, and endothelial dysfunction as key mediators of disease progression. Adjunctive therapies such as sodium-glucose cotransporter-2 (SGLT2) inhibitors, glucagon-like peptide-1 (GLP-1) agonists, and mineralocorticoid receptor antagonists (MRAs) demonstrate significant cardiovascular and renal benefits in conditions including heart failure and chronic kidney disease. These drugs also modulate pathways involved in the pathophysiology of FD, such as autophagy, oxidative stress, and pro-inflammatory cytokine signaling. While theoretical foundations support their utility, dedicated trials are necessary to confirm efficacy in the FD-specific population. This narrative review highlights the importance of expanding therapeutic strategies in FD, advocating for a multi-faceted approach involving evidence-based adjunctive treatments to improve outcomes. Tailored research focusing on diverse FD phenotypes, including females and non-classical variants of disease, will be critical to advancing care and improving outcomes in this complex disorder.

Epidemiology and early predictors of Fabry nephropathy: evaluation of long-term outcomes from a national Fabry centre

BACKGROUND

Fabry disease is a rare genetic lysosomal storage disorder, whereby the accumulation of sphingolipids consequently leads to kidney structural damage and dysfunction. We explored the epidemiology of chronic kidney disease (CKD) among patients with Fabry disease at a major UK referral centre in Greater Manchester serving over 7 million people, to inform early predictors of kidney disease and possible treatment planning.

METHODS

Data were sourced from the electronic records of registered participants from November 2020 to February 2022 of adults diagnosed with Fabry disease, with at least 1 year of follow-up. Four hundred and five participants (female = 223, male = 182) met the initial eligibility criteria. Our study focused on identifying factors linked to incident CKD, with 395 evaluable individuals undergoing outcome analysis over a median of 6.4 years.

RESULTS

Findings concluded that 60.5% of participants received disease-modifying treatments, 29.7% experienced non-fatal cardiovascular events, 3.3% developed end-stage kidney disease (ESKD), and 7.3% died. Men had higher use of disease modifying therapy, progression to ESKD requiring kidney replacement therapy, cardiovascular events, and mortality compared to women. Subgroup analysis over 9 years revealed that older age, cardiovascular history, renin-angiotensin-aldosterone system inhibitor use, and higher urine albumin-to-creatinine ratio (uACR) were predictors of faster estimated glomerular filtration rate (eGFR) decline and increased mortality. At baseline, 47.8% of 249 patients with uACR data had CKD, and 25.4% of the remaining individuals developed CKD during follow-up, associated with higher uACR and lower, albeit normal eGFR levels.

CONCLUSION

Over 60% of Fabry disease patients are at lifetime risk of developing CKD, with a substantial risk of mortality, even with initially normal uACR and eGFR values.

Impact of enzyme replacement therapy and migalastat on disease progression in females with fabry disease

AIM

The aim of our multicenter study was to investigate the safety and efficacy of enzyme replacement therapy (ERT) and chaperone therapy on the disease progression in female Fabry disease (FD) patients and to compare the individual treatment regimens.

METHODS

Data from 3 consecutive visits of 102 female FD patients from 6 Fabry centers were retrospectively analyzed. According to their FD-specific treatment, patients were separated in 5 groups: Newly agalsidase-beta- [n = 18], agalsidase-alfa- [n = 29] and migalastat-[n = 14] treated patients, and long-term agalsidase-beta- [n = 7] and agalsidase-alfa-[n = 34] treated patients. Clinical presentation and laboratory data, including plasma lyso-Gb3 levels were assessed.

RESULTS

Treatment with agalsidase-beta, agalsidase-alfa, and migalastat was safe and severe adverse events were rare. Newly and long-term-treated patients presented a stable disease course over time. None of the patients required hospitalization due to cardiac events. Overall septum thickness remained stable in all groups (p > 0.05). Estimated glomerular filtration rate (eGFR) only slightly decreased in patients treated with agalsidase-alfa [newly- and long-term-treated: -1.5 ± 3.2 and - 1.3 ± 3.9 ml/min/1.73 m²/year; p = 0.0056 and p = 0.0187, respectively] but the decrease was in the range of natural eGFR decline. eGFRs in agalsidase-beta and migalastat-treated patients were stable. No clinically relevant differences concerning treatment efficacy between agalasidase-beta, agalsidase-alfa, and migalastat were detected.

CONCLUSION

We conclude that treatment of females with agalsidase-beta, agalsidase-alfa, and migalastat was safe. Independent of the chosen treatment regimen, nearly all patients presented with a stable disease course over time. In our cohort, a comparison of therapy efficacies showed no relevant clinical differences between the groups.

Telomere Length, Oxidative Stress, and Kidney Damage Biomarkers in Fabry Nephropathy

Fabry nephropathy is a life-threatening complication of Fabry disease characterized by complex and incompletely understood pathophysiological processes possibly linked to premature aging. We aimed to investigate leukocyte telomere length (LTL), oxidative stress, and kidney damage biomarkers in relation to kidney function. The study included 35 Fabry patients and 35 age and sex-matched control subjects. Based on the estimated slope of the glomerular filtration rate, the patients were divided into two groups. Relative LTL was quantified by qPCR, urinary biomarkers 8-hydroxy-2'-deoxyguanosine (8-OHdG) and malondialdehyde (MDA) by UHPLC-MS/MS, and kidney damage biomarkers by flow cytometry. There was no statistically significant difference in LTL between Fabry patients and controls. However, a significant difference was observed in male patients compared to their matched control subjects (p = 0.013). Oxidative stress biomarkers showed no differences between patients and controls, while significant differences were observed in urinary IGFBP7, EGF, and OPN levels between Fabry patients with stable kidney function and those with progressive nephropathy (FDR = 0.021, 0.002, and 0.013, respectively). Significant differences were also observed in plasma levels of cystatin C, TFF3, and uromodulin between patients with progressive nephropathy and controls (all FDR = 0.039). Along with these biomarkers (FDR = 0.007, 0.017, and 0.010, respectively), NGAL also exhibited a significant difference between the two patient groups (FDR = 0.017). This study indicates accelerated telomere attrition, which may be related to disease burden in males. Furthermore, analyses of urinary oxidative stress markers revealed no notable disparities between the different kidney function groups, indicating their limited utility. However, promising differences were found in some biomarkers of kidney damage in urine and plasma.

Effects of Current Therapies on Disease Progression in Fabry Disease: A Narrative Review for Better Patient Management in Clinical Practice

Fabry disease (FD) is a rare lysosomal storage disorder that is characterized by renal, neurological, and cardiovascular dysfunction. Four treatments are currently available for patients with FD; three enzyme replacement therapies (ERTs; agalsidase alfa, agalsidase beta, and pegunigalsidase alfa) and one pharmacological chaperone (migalastat). This review focuses on the evidence for the benefits of ERTs and migalastat, and provides an overview of their impact on disease manifestations and quality of life (QoL). Agalsidase beta is associated with renal, neurological, and cardiovascular benefits, and may prevent renal disease progression. Agalsidase alfa provides stabilizing effects across all main organ systems, although minor sex-specific differences exist in patients with more advanced baseline disease. The benefits of agalsidase alfa and agalsidase beta are similar but depend on the extent of baseline disease. Some data indicate that agalsidase beta may be preferable over the longer term. Both agalsidase alfa and agalsidase beta are associated with improved gastrointestinal and pain symptoms, as well as improved QoL. Patients with advanced end-organ damage tend not to respond as optimally to ERTs as those who initiate ERTs before irreversible organ fibrosis develops, highlighting the need for early treatment initiation. Migalastat, which is only approved for patients with amenable missense gene variants, generally stabilizes renal parameters and provides cardiovascular benefits. Migalastat also improves diarrhea and pain, and stabilizes QoL (although ERT may be more effective for pain management), but the neurological effects of migalastat have not been studied. Real-world data raise concerns about effective in vivo amenability of some genetic variants. Future studies with direct treatment comparisons in patients with FD are needed.

Imaging predictors of adverse prognosis in Fabry disease cardiomyopathy: A systematic review and meta-analysis

BACKGROUND

Cardiac involvement represents the main cause of death in patients with Fabry disease (FD). Echocardiography and cardiovascular magnetic resonance (CMR) have an established diagnostic role, but their prognostic value remains unresolved. This systematic review and meta-analysis sought to assess the prognostic implications of imaging parameters in FD.

METHODS

PubMed, ClinicalTrials.gov, Embase, Cochrane Library and Web of Science databases were searched for studies from inception through 1 May 2024. Studies including FD patients undergoing baseline imaging assessment and clinical follow-up were selected. Pre-defined study outcomes were a cardiovascular endpoint and a composite clinical endpoint. The study protocol was registered in PROSPERO (ID CRD42022342394).

RESULTS

Fourteen studies, including 1713 FD patients (44.7% males), were selected. At pooled analysis, late gadolinium enhancement (hazard ratio [HR]: 4.45; 95% CI: 2.82-7.02), left atrium volume indexed (HR: 1.02 per mL/m2; 95% CI: 1.01-1.03), E/e' (HR: 1.14 per unit increase; 95% CI: 1.08-1.21), left ventricular (LV) mass indexed (HR: 1.01 per mg/m2; 95% CI: 1.00-1.02), maximum LV wall thickness (HR: 1.19 per mm, 95% CI: 1.04-1.36) and LV-global longitudinal strain (HR: 1.20 per unit increase; 95% CI: 1.16-1.25) were significantly associated with the cardiovascular endpoint, whereas T1-mapping and LV-ejection fraction were not. T1-mapping was associated with the composite endpoint (HR: 0.99 per msec increase; 95% CI: 0.98-1.00). Meta-regression analysis did not show any significant interaction between each of the potential effect modifiers.

CONCLUSIONS

Several imaging parameters were significant predictors of adverse clinical outcomes in patients with FD. Late gadolinium enhancement showed the strongest association with adverse prognosis.

Clinical management of female patients with Fabry disease based on expert consensus

Fabry disease is an X-linked lysosomal storage disorder that causes accumulation of glycosphingolipids in body tissues and fluids, leading to progressive organ damage and life-threatening complications. It can affect both males and females and can be classified into classic or later-onset phenotypes. The disease severity in females ranges from asymptomatic to the more severe, classic phenotype. Most females are hemizygous and the X-linked inheritance is associated with variable X-activation pattern and residual enzymatic activity. The heterogeneity of clinical presentation in females requires different approaches to diagnosis and management than males. A European group of 7 physicians, experienced in the management of Fabry disease, convened to discuss patient perspectives and published guidelines. The experts discussed the need to focus on psychological treatment in relation to individual coping styles when monitoring targets, and the lack of data supporting the use of plasma globotriaosylsphingosine over enzyme activity in the diagnosis of these patients. It was suggested that the high phenotypic variability in female patients may be related to the dynamic nature of the X-chromosome inactivation process and further understanding of this process could help predict the progression of Fabry disease in females and facilitate timely intervention. Due to the range of disease severity they exhibit, female patients with Fabry disease may require a more individualized treatment approach than males. Despite current recommendations, the experts agreed that early disease-specific treatment initiation in high-risk females could improve clinical outcome.

Renal and multisystem effectiveness of 3.9 years of migalastat in a global real-world cohort: Results from the followME Fabry Pathfinders registry

Fabry disease is a progressive, X-linked lysosomal disorder caused by reduced or absent α-galactosidase A activity due to GLA variants. The effects of migalastat were examined in a cohort of 125 Fabry patients with migalastat-amenable GLA variants in the followME Pathfinders registry (EUPAS20599), an ongoing, prospective, patient-focused registry evaluating outcomes for current Fabry disease treatments. We report annualised estimated glomerular filtration rate (eGFR) and Fabry-associated clinical events (FACEs) in a cohort of patients who had received ≥3 years of migalastat treatment in a real-world setting. As of August 2022, 125 patients (60% male) had a mean migalastat exposure of 3.9 years. At enrolment, median age was 58 years (males, 57; females, 60) with a mean eGFR of 83.7 mL/min/1.73 m2 (n = 122; males, 83.7; females, 83.8) and a median left ventricular mass index of 115.1 g/m2 (n = 61; males, 131.2; females, 98.0). Mean (95% confidence interval) eGFR annualised rate of change in the overall cohort (n = 116) was -0.9 (-10.8, 9.9) mL/min/1.73 m2/year with a similar rate of change observed across patients with varying levels of kidney function at enrolment. Despite population age and baseline morbidity, 80% of patients did not experience a FACE during the mean 3.9 years of migalastat exposure. The incidence of renal, cardiac, and cerebrovascular events was 2.0, 83.2, and 4.1 events per 1000 patient-years, respectively. These data support a role of migalastat in preserving renal function and multisystem effectiveness during ≥3 years of migalastat treatment in this real-world Fabry population.

Impact of enzyme replacement therapy on clinical manifestations in females with Fabry disease

BACKGROUND

The aim of our multicenter study was to investigate the implementation of the European Fabry guidelines on therapeutic recommendations in female patients with Fabry disease (FD) and to analyze the impact of enzyme replacement therapy (ERT) in treated and untreated females.

RESULTS

Data from 3 consecutive visits of 159 female FD patients from 6 Fabry centers were retrospectively analyzed. According to their treatment, patients were separated in 3 groups (untreated, n = 71; newly ERT-treated, n = 47; long-term ERT-treated, n = 41). Clinical presentation and laboratory data, including plasma globotriaosylsphingosine (lyso-Gb3) levels were assessed. The observation time ranged from 49 to 62 months. ∼90% of female patients treated with ERT presented with at least one organ manifestation justifying treatment according to current European guidelines. Untreated females showed a less severe disease load with less FD-typical organ damage. All groups presented with a stable cardiac status (all p > 0.05) over time. ERT-treated females presented with a slight yearly loss of estimated glomerular filtration (eGFR) over time (both p < 0.05), which was comparable to the natural decline for this age. Plasma lyso-Gb3 levels were higher in ERT-treated females and decreased by 0.95 [-4.44 to 4.08] ng/ml/year (p = 0.0002) in those who were newly ERT-treated.

CONCLUSIONS

Severely affected females with FD who were treated with ERT, and less severely affected untreated females, showed a broadly stable disease course over 5 years. The treatment decisions were largely based on the European guidelines for FD. In untreated females, it is crucial to explore if organ involvement is FD-related in order to make the correct treatment decision.

Role of Longitudinal Strain in the Evaluation of Contractile Dysfunction in Japanese Fabry Disease Patients

BACKGROUND

Fabry disease is a hereditary metabolic disorder caused by a decrease in or deficiency of the lysosomal enzyme α-galactosidase A. Enzyme replacement therapy or pharmacological chaperone therapy can improve prognosis, especially in patients in the early phase of cardiac involvement. Longitudinal strain (LS) evaluated using speckle tracking echocardiography can detect early contractile dysfunction. However, there have been no reports of LS in Japanese Fabry disease patients.

METHODS AND RESULTS

We recruited 56 patients with Fabry disease (22 men, 34 women) who were followed up at Jikei University Hospital. Fifty-eight control subjects without overt cardiac diseases were also included in the study. We evaluated LS in each patient, and the values of each of the 17 segments of the left ventricle (LV) were averaged, and global LS (GLS) was also calculated. GLS was significantly worse in Fabry disease patients without LV hypertrophy than in control subjects (-18.5±2.8% vs. -20.4±1.6%; P<0.05). In addition, Fabry disease patients without LV hypertrophy had significantly worse lateral LS (-16.4±5.0% vs. -19.3±1.8%; P<0.05), basal LS (-16.5±3.2% vs. -18.5±1.7%; P<0.05), and mid LS (-18.7±1.7% vs. -20.8±1.6%; P<0.05) than control subjects.

CONCLUSIONS

These results suggest that early contractile dysfunction in Fabry disease can be observed using GLS, lateral LS, basal LS, and mid LS, even without LV hypertrophy.

Anderson-Fabry Disease: Focus on Ophthalmological Implications

Fabry disease (FD) is a rare X-linked lysosomal storage disorder with a broad spectrum of clinical manifestations, including severe complications, such as end-stage renal disease, hypertrophic cardiomyopathy, and cerebrovascular disease. Enzyme replacement therapy (ERT), when initiated early, has been shown to reduce the incidence of severe events and slow disease progression. In the classic form, characterized by the absence of α-galactosidase A (α-Gal A) enzyme activity, diagnosis is straightforward. However, when residual activity is present, the delayed and less obvious presentation can make diagnosis more challenging. Ophthalmological alterations, which can be detected through non-invasive examinations may play a crucial role in correctly assessing the patient in terms of diagnosis and prognosis, particularly in these atypical cases. Recognizing these ocular signs allows for timely intervention with ERT, leading to improved patient outcomes. This review highlights the importance of ophthalmological findings in FD, emphasizing their role in diagnosis and treatment planning. By raising awareness among ophthalmologists and healthcare specialists, this review aims to improve disease management, offering tools for early detection and better long-term prognosis in patients with FD.

Promise and Peril of a Genotype-First Approach to Mendelian Cardiovascular Disease

Precision medicine, which among other aspects includes an individual's genomic data in diagnosis and management, has become the standard-of-care for Mendelian cardiovascular disease (CVD). However, early identification and management of asymptomatic patients with potentially lethal and manageable Mendelian CVD through screening, which is the promise of precision health, remains an unsolved challenge. The reduced costs of genomic sequencing have enabled the creation of biobanks containing in-depth genetic and health information, which have facilitated the understanding of genetic variation, penetrance, and expressivity, moving us closer to the genotype-first screening of asymptomatic individuals for Mendelian CVD. This approach could transform health care by diagnostic refinement and facilitating prevention or therapeutic interventions. Yet, potential benefits must be weighed against the potential risks, which include evolving variant pathogenicity assertion or identification of variants with low disease penetrance; costly, stressful, and inappropriate diagnostic evaluations; negative psychological impact; disqualification for employment or of competitive sports; and denial of insurance. Furthermore, the natural history of Mendelian CVD is often unpredictable, making identification of those who will benefit from preventive measures a priority. Currently, there is insufficient evidence that population-based genetic screening for Mendelian CVD can reduce adverse outcomes at a reasonable cost to an extent that outweighs the harms of true-positive and false-positive results. Besides technical, clinical, and financial burdens, ethical and legal aspects pose unprecedented challenges. This review highlights key developments in the field of genotype-first approaches to Mendelian CVD and summarizes challenges with potential solutions that can pave the way for implementing this approach for clinical care.

Role of standard echocardiography in Anderson-Fabry disease

Cardiac involvement strongly impacts prognosis in patients with Anderson-Fabry disease (AFD). All cardiac structures, such as the left ventricle and the left atrium, the aorta, the right sections, and the heart valves can be affected by morphological and functional abnormalities. Standard echocardiography has a crucial role in the characterization of AFD cardiomyopathy. Being a diffuse, non-invasive, easily reproducible, and inexpensive investigation, echocardiography represents the most appropriate tool for screening AFD cardiomyopathy. Furthermore, echocardiographic evaluation is the essential imaging method to support the physician also in the follow-up and risk stratification of AFD patients. Therefore, echocardiography is useful in all stages of the disease, both to reveal the first signs of cardiac involvement and to guarantee timely treatment in the preclinical stage and to estimate the extent of cardiac involvement, define possible complications, and evaluate the response to treatment in patients with established cardiomyopathy. The latest advanced echocardiographic techniques, such as speckle-tracking analysis, are offering new insights into the early detection of AFD cardiac involvement, thus suggesting a promising role for echocardiography in selecting appropriate candidates for treatment. In this review, we will examine the role of standard echocardiography in AFD, focusing on its use in screening for cardiac involvement, detailed characterization of AFD cardiomyopathy, and risk stratification of AFD patients.

[Lysosomal storage disorders - Fabry disease and Gaucher disease]

Lysosomal storage disorders (LSD) are a heterogenous group of inborn errors of metabolism due to lysosomal malfunction. LSDs affect 1 in 5000 live births, albeit every LSD itself has a low incidence. The most common LSDs are Fabry disease and Gaucher disease. The underlying cause mainly is an enzyme deficiency but may also be due to defects in transport or activation proteins, which result in progressive intra- and extra-lysosomal accumulation of undegraded storage material. The lysosomes play a key role in degradation and cellular recycling of macromolecules. Besides disturbance of cellular function, substrate accumulation may result in secondary toxic and/or inflammatory processes. For treatment of Fabry and Gaucher disease, several therapeutic approaches are approved including enzyme replacement therapy, chaperon therapy for Fabry disease and substrate reduction therapy for Gaucher disease.

Fabry disease: a rare disorder calling for personalized medicine

Fabry Disease (FD) is a genetic disease caused by a deficiency in the activity of lysosomal galactosidase A (α-GalA), an enzyme responsible for the catabolism of globotriaosylceramide (Gb3). Since lysosomes are present throughout the body and play a crucial role in catabolism and recycling of cytosolic compounds, FD can affect multiple organs and result in various symptoms, including renal, cardiovascular, neurological, cutaneous, and ophthalmic manifestations. Due to the nonspecific symptoms and the rarity of FD, it is often diagnosed late in life. However, introducing targeted therapies such as enzyme replacement therapy (ERT) and chaperone therapy has significantly improved FD's natural history and prognosis by restoring α-GalA enzyme activity. Despite the advancements, there are limitations to the currently available therapies, which has prompted research into new potential treatments for FD, including alternative forms of enzyme replacement therapy, substrate reduction therapy, mRNA therapy, and genetic therapy. In this review, we analyze the epidemiology, pathophysiology, and treatment of FD, with particular emphasis on promising therapeutic opportunities that could shift the treatment of this rare disease from a standardized to a personalized approach soon.

Insights of Fabry disease: Expert consensus approach for screening, diagnosis, and multidisciplinary management in chronic kidney disease

The prevalence of Fabry disease (FD) among males with chronic kidney disease (CKD) of unknown etiology in Taiwan is 0.6%. Despite this, FD is frequently overlooked in clinical settings. To address this issue, two consensus meetings were conducted in Taiwan-one in August 2022 and another in April 2023. The first meeting established screening criteria based on age, gender, family history, cardiac involvement, and symptoms. The second meeting, with a multidisciplinary team, developed treatment recommendations. The consensus emphasizes the importance of proactive data collection in dialysis units and outpatient follow-ups to enhance FD detection and management. The screening algorithm recommends incorporating FD screening into the diagnostic process for CKD patients, regardless of age. Priority is given to patients with a family history of FD, early stroke history, or classical FD symptoms. Comprehensive screening is also advised for CKD patients without obvious classical symptoms. Screening protocols for males include measuring α-galactosidase A enzyme activity, with reduced activity leading to further tests such as lyso-Gb3 level quantification and genetic analysis. For females, the protocol involves evaluating lyso-Gb3 plasma levels and genetic testing. FD, though often underestimated, is more prevalent than recognized and necessitates a multidisciplinary approach for timely diagnosis. Enhancing awareness and adopting a comprehensive approach are essential for improving patient outcomes.

Prevalence of Fabry Disease in Patients on Dialysis in France

Numerous prevalence studies on Fabry disease (FD, OMIM #301500) have been conducted in dialysis populations across the world with variable and controversial results. The FABRYDIAL study aimed to estimate the prevalence of FD in patients aged 18 to 74 years on chronic dialysis in France. This cross-sectional study was conducted in patients undergoing dialysis. One hundred and twenty-four dialysis centers participated. Patients with proven causes of nephropathy unrelated to FD were excluded. Alpha-galactosidase A activity was assayed in men, and both α-galactosidase A and lyso-Gb3 were assayed in women from dried blood spots. GLA gene sequencing was performed in case of abnormal values. If a variant was identified, a diagnosis validation committee was consulted for adjudication. Among the 6032 targeted patients, 3088 were included (73.6% of the eligible patients). Biochemical results were available for 2815 (1721 men and 1094 women). A genetic variant of GLA was identified in five patients: a benign c.937G>T/p.(Asp313Tyr) variant in two individuals, a likely benign c.427G>A/(p.Ala143Thr) variant, a likely benign c.416A>G/(p.Asn139Ser) variant, and a pathogenic c.1185dupG/p.Phe396Glyfs variant. Among the screened patients, the prevalence was 0.058% [0.010;0.328] in males, 0% [0.000;0.350] in females, and 0.035% [0.006;0.201] when both genders were pooled. Among all patients aged 18-74 years undergoing dialysis without a previously known cause of nephropathy unlinked to FD, the prevalence was 0.028% [0.006;0.121]. The prevalence of FD in a cohort of French dialysis patients was low. However, considering the prognostic impact of earlier diagnosis, signs of FD should be sought in patients with nephropathies of uncertain etiology.

Experts' Opinion in Fabry Disease Management and the Unmet Medical Need: The Saudi Perspective

Fabry disease (FD) is an X-linked lysosomal storage disorder caused by α-galactosidase A gene mutations. Its global incidence ranges from 1:40,000 to 1:170,000. This expert review evaluates the available guidelines, the status of diagnosed but untreated patients with FD, and the challenges in diagnosing and managing FD in the Kingdom of Saudi Arabia (KSA). An advisory board meeting (ABM) was conducted in two phases, with a survey that aimed to receive insights on the current unmet needs in the management of patients with FD in November 2022, and a second, offline meeting in February 2023. The goal of this ABM was to discuss current unmet needs in the management of Fabry patients in the Kingdom of Saudi Arabia. In the first ABM, experts opined on the best practices in the diagnosis, screening, and management of FD for healthcare professionals. These opinions on the management of FD relied on data from research and expert clinical judgments. In the second ABM, the same panel discussed different aspects of FD diagnosis, treatment, and management in the member countries of the Gulf Cooperation Council. The experts discussed the stigma associated with FD, patient awareness and knowledge, genetic screening, biomarkers, and home infusion therapy. They reviewed international guidelines and clinical criteria for enzyme replacement therapy (ERT). Furthermore, they also discussed the diagnosis of FD in men and women, the current guidelines followed for monitoring patients with FD, monitoring untreated patients with FD, Fabry Stabilization IndeX (FASTEX) as an assessment tool for the diagnosis of FD, FD management in KSA, challenges encountered while prescribing ERT in patients with FD, and the clinical criteria for starting ERT. The discussions led to the conclusion that currently, ERT is the only available therapy to manage FD and research should be focused on the early diagnosis and management of FD.

Clinical outcomes in elderly patients receiving agalsidase alfa treatment in the Fabry Outcome Survey

BACKGROUND AND OBJECTIVES

Treatment with agalsidase alfa in patients with Fabry disease is most effective when initiated early in the disease course; however, the clinical benefits in elderly patients are less well established. This analysis assesses outcomes in patients aged 65 years or older from the Fabry Outcome Survey (FOS) who were treated with agalsidase alfa.

METHODS

FOS data were extracted for adult patients aged 65 years or older who received agalsidase alfa, had baseline data and at least 3 years of post-baseline data, and had undergone no renal transplantation and/or dialysis before treatment. The data of patients who had undergone renal transplantation and/or dialysis during follow-up were excluded from estimated glomerular filtration rate (eGFR) analysis after the date of the renal transplantation and/or dialysis. Adult patients were stratified into two groups: those who started treatment before 65 years of age and who were still being treated when aged 65 years or older (group A), and those who started treatment when aged 65 years or older (group B). Mean annual changes in left ventricular mass index (LVMI), eGFR and proteinuria were assessed in group A (before and after the age of 65 years to understand if there was an age-related effect once patients turned 65 years of age) and in group B.

RESULTS

Estimated mean (standard error [SE]) annual changes in LVMI were 0.46 (0.26) g/m2.7 and 0.21 (0.42) g/m2.7 in patients in group A when they were younger than 65 years and when they were aged 65 years or older, respectively, and 0.12 (0.65) g/m2.7 in patients in group B. For eGFR, mean (SE) annual changes were 0.83 (2.12) mL/min/1.73 m2 and 2.64 (2.18) mL/min/1.73 m2 in patients in group A when they were younger than 65 years and when they were aged 65 years or older, respectively, and 2.31 (1.44) mL/min/1.73 m2 in patients in group B. Proteinuria remained relatively stable in both subgroups of group A (before and after the age of 65 years) and group B.

CONCLUSIONS

Continuation and initiation of agalsidase alfa treatment in patients aged 65 years or older with Fabry disease were associated with stabilization of proteinuria and minimal increases in cardiac (LVMI) and renal (eGFR) outcomes.

2024 Update of the TSOC Expert Consensus of Fabry Disease

As an X-linked inherited lysosomal storage disease that is caused by α-galactosidase A gene variants resulting in progressive accumulation of pathogenic glycosphingolipid (Gb3) accumulation in multiple tissues and organs, Fabry disease (FD) can be classified into classic or late-onset phenotypes. In classic phenotype patients, α-galactosidase A activity is absent or severely reduced, resulting in a more progressive disease course with multi-systemic involvement. Conversely, late-onset phenotype, often with missense variants (e.g., IVS4+919G>A) in Taiwan, may present with a more chronic clinical course with predominant cardiac involvement (cardiac subtype), as they tend to have residual enzyme activity, remaining asymptomatic or clinically silent during childhood and adolescence. In either form, cardiac hypertrophy remains the most common feature of cardiac involvement, potentially leading to myocardial fibrosis, arrhythmias, and heart failure. Diagnosis is established through α-galactosidase enzyme activity assessment or biomarker analyisis (globotriaosylsphingosine, Lyso-Gb3), advanced imaging modalities (echocardiography and cardiac magnetic resonance imaging), and genotyping to differentiate FD from other cardiomyopathy. Successful therapeutic response relies on early recognition and by disease awareness from typical features in classic phenotype and cardiac red flags in cardiac variants for timely therapeutic interventions. Recent advances in pharmacological approach including enzyme replacement therapy (agalsidase alfa or beta), oral chaperone therapy (migalastat), and substrate reduction therapy (venglustat) aim to prevent from irreversible organ damage. Genotype- and gender-based monitoring of treatment effects through biomarker (Lyso-Gb3), renal assessment, and cardiac responses using advanced imaging modalities are key steps to optimizing patient care in FD.

Case report: First diagnosis of Fabry disease in North Macedonia in a patient presenting with kidney failure on hemodialysis

Introduction

Fabry disease is a rare X-linked lysosomal storage disorder caused by α-galactosidase A (α-Gal A) deficiency. Reduced or absent enzyme activity causes progressive lysosomal accumulation of globotriaosylceramide (Lyso-Gb3) in various cells throughout the body to trigger inflammation and fibrosis.

Case description

We present the first familial case of Fabry Disease in North Macedonia identified based on clinical manifestations and confirmed through enzyme, biomarker, and genetic tests. The index case in the family was a 45-year-old male undergoing hemodialysis therapy. He has had chronic burning uncontrolled limb pain since childhood, intermittent abdominal cramps, anhidrosis, and hypertension. The constellation of clinical presentations accompanied by similar symptoms in close family members prompted the enzyme, biomarker, and genetic analyses for Fabry disease. Genetic testing identified a known pathogenic GLA missense variant c.443G>A or p.(Ser148Asn) in the hemizygous state. Subsequent family studies allowed identification of another hemizygous male and five heterozygous female carriers affected by this X-linked disorder.

Conclusion

We report identification of the first familial case of Fabry disease in North Macedonia and describe the phenotype associated with the Ser148Asn GLA variant. Greater awareness of this rare disease linked to continuous medical education is crucial for timely diagnosis and treatment.

Contemporary Multimodality Imaging for Diagnosis and Management of Fabry Cardiomyopathy

Fabry disease (FD) is an X-linked lysosomal storage disorder which leads to the accumulation of globotriaosylceramide (Gb3) in various organs, including the heart. FD can be subdivided into classic disease resulting from negligible residual enzyme activity and a milder, atypical phenotype with later onset and less severe clinical presentation. The use of multimodality cardiac imaging including echocardiography, cardiac magnetic resonance and nuclear imaging is important for the diagnostic and prognostic evaluation in these patients. There are gaps in the literature regarding the comprehensive description of cardiac findings of FD and its evaluation by multimodality imaging. In this review, we describe the contemporary practices and roles of multimodality cardiac imaging in individuals affected with Fabry disease.

Prognostic Implications of Left Ventricular Hypertrophy and Mechanical Function in Fabry Disease: A Longitudinal Cohort Study

BACKGROUND

The prognostic value of different grades of left ventricular hypertrophy (LVH) and left ventricular (LV) mechanical function in Fabry disease is unclear. We aimed to evaluate the association between the severity of LVH, LV mechanical function, and clinical outcomes in Fabry disease.

METHODS

We conducted a retrospective cohort study from a single-center registry of adult patients with Fabry disease. Left ventricular mass index (LVMI) was measured by echocardiography. The severity of LVH was categorized by LVMI using the sex-specific cutoff values. Left ventricular mechanical function was measured as LV global longitudinal strain (GLS) by speckle-tracking analysis. The primary outcome was a composite of major adverse cardiovascular events (MACE) at 5 years, including heart failure hospitalization, sustained ventricular tachycardia, acute ischemic stroke, and all-cause mortality.

RESULTS

The study included 268 patients (age 50.4 ± 15.4 years, men 46.6%) with Fabry disease (83.2% IVS4+919G > A mutation), and 106 patients (39.6%) had LVH. Patients with mild, moderate, or severe LVH had 5-year MACE rates of 7.4%, 10%, and 30.5%, respectively (P < .001). Moreover, patients with impaired LV GLS (<14.1%) had a higher 5-year MACE rate than those with preserved LV GLS (32.1% vs 2.4%, P < .001). Severe LVH was an independent predictor of MACE compared with absence of LVH (adjusted hazard ratio, 12.73; 95% CI, 1.3-124.71; P = .03), after adjusting for age, sex, hypertension, hyperlipidemia, atrial fibrillation, renal function, average E/e', enzyme replacement therapy, and LV GLS. Patients with severe LVH and impaired LV GLS had the highest incidence for MACE (log-rank P < .05), irrespective of sex, genotypes, and whether receiving enzyme replacement therapy or not.

CONCLUSIONS

Sex-specific grading of LVH by LVMI is practical for risk stratification in patients with Fabry disease, and impaired LV GLS further refines the prognostication.

Cardiac Manifestations in Inherited Metabolic Diseases

Inherited metabolic diseases (IMDs) stem from genetic defects affecting enzyme function within specific metabolic pathways, collectively constituting rare conditions with an incidence of less than 1/100,000 births. While IMDs typically manifest with multisystemic symptoms, cardiac manifestations are common, notably hypertrophic cardiomyopathy. Additionally, they can lead to dilated or restrictive cardiomyopathy, as well as noncompacted left ventricular cardiomyopathy. Rhythm disturbances such as atrioventricular conduction abnormalities, Wolff-Parkinson-White syndrome, and ventricular arrhythmias, along with valvular pathologies and ischemic coronary issues, are also prevalent. This study aims to provide a narrative review of IMDs associated with cardiac involvement, delineating the specific cardiac manifestations of each disorder alongside systemic symptoms pivotal for diagnosis.

An Atypical Presentation of Fabry Disease in a Patient With Nephrotic Syndrome: A Case Report

Fabry disease is a rare X-linked lysosomal storage disorder that leads to the accumulation of globotriaosylceramide (Gb3) across various tissues, stemming from a deficiency in alpha-galactosidase A (GLA). This condition is characterized by a spectrum of clinical manifestations that can significantly complicate diagnosis. Classical symptoms typically include neuropathic pain, angiokeratomas, and significant involvement of the renal and cardiac systems. However, atypical presentations may obscure the underlying diagnosis, emphasizing the importance of maintaining a high level of clinical suspicion. This case report details the diagnostic journey of a 24-year-old female who initially presented with nephrotic syndrome, a presentation not commonly associated with Fabry disease. Subsequent genetic testing revealed a pathogenic variant in the GLA gene, confirming Fabry disease and highlighting the critical need for genetic analysis in cases of unexplained renal pathology. This case underscores the variability of Fabry disease presentations and the pivotal role of comprehensive diagnostic strategies in uncovering this complex disorder.

Experience with cascade screening: A comprehensive family pedigree analysis of two index patients with Fabry disease

The wide range of clinical symptoms observed in patients with Fabry disease (FD) often leads to delays in diagnosis and initiation of treatment. Delayed initiation of therapy may result in end-organ damage, such as chronic renal failure, hypertrophic cardiomyopathy, and stroke. Although some tools are available to identify undiagnosed patients, new comprehensive screening methods are needed. In this study, the outcomes of the cascade screening applied to three index cases with FD from 2 familes were investigated. In the pedigree analysis, 280 individuals were included; out of them, 131 individuals underwent genetic testing and cascade screening for FD. During the screening program, a total of 45 individuals were diagnosed, with a diagnostic ratio of 1:15. The average age at diagnosis for all individuals was 30.9 ± 17.7 years, and %25 were pediatric cases (mean age 9.5 ± 5.9 years). Thirty affected relatives were diagnosed from the two index cases in Family 1 and 15 individuals were diagnosed from one index case in Family 2. There were 13 consanguineous marriages observed among 2 pedigres, in two both spouses  were affected, leading to two homozygous affected daughters in one couple. In regions where there is a high prevalence of consanguineous marriages, implementing the cascade screening approach to identify all individuals at risk can be beneficial for patients with FD, specifically women and children.

Cardiac manifestations in inherited metabolic diseases

Inherited metabolic diseases (IMD) are caused by the functional defect of an enzyme, of genetic origin, that provokes a blockage in a specific metabolic pathway. Individually, IMD are considered rare diseases, with an incidence of less than 1/100,000 births. The symptoms are usually multisystemic, but frequently include cardiac manifestations. Of these, the most common are cardiomyopathies, especially hypertrophic cardiomyopathy. In addition, they can cause dilated or restrictive cardiomyopathy and non-compacted cardiomyopathy of the left ventricle. Characteristic signs also include rhythm alterations (atrio-ventricular conduction disturbances, Wolff-Parkinson-White syndrome or ventricular arrhythmias), valvular pathology and ischaemic coronary pathologies. The aim of this study is to present a narrative review of the IMD that may produce cardiac involvement. We describe both the specific cardiac manifestations of each disease and the systemic symptoms that guide diagnosis.

Effects of Enzyme Replacement Therapy on Cardiac MRI Findings in Fabry Disease: A Systematic Review and Meta-Analysis

Purpose To perform a systematic review and meta-analysis to assess the effect of enzyme replacement therapy on cardiac MRI parameters in patients with Fabry disease. Materials and Methods A systematic literature search was conducted from January 1, 2000, through January 1, 2024, in PubMed, ClinicalTrials.gov, Embase, and Cochrane Library databases. Study outcomes were changes in the following parameters: (a) left ventricular wall mass (LVM), measured in grams; (b) LVM indexed to body mass index, measured in grams per meters squared; (c) maximum left ventricular wall thickness (MLVWT), measured in millimeters; (d) late gadolinium enhancement (LGE) extent, measured in percentage of LVM; and (e) native T1 mapping, measured in milliseconds. A random-effects meta-analysis of the pooled mean differences between baseline and follow-up parameters was conducted. The study protocol was registered in PROSPERO (CRD42022336223). Results The final analysis included 11 studies of a total of 445 patients with Fabry disease (mean age ± SD, 41 years ± 11; 277 male, 168 female). Between baseline and follow-up cardiac MRI, the following did not change: T1 mapping (mean difference, 6 msec [95% CI: -2, 15]; two studies, 70 patients, I2 = 88%) and LVM indexed (mean difference, -1 g/m2 [95% CI: -6, 3]; four studies, 290 patients, I2 = 81%). The following measures minimally decreased: LVM (mean difference, -18 g [95% CI: -33, -3]; seven studies, 107 patients, I2 = 96%) and MLVWT (mean difference, -1 mm [95% CI: -2, -0.02]; six studies, 151 patients, I2 = 90%). LGE extent increased (mean difference, 1% [95% CI: 1, 1]; three studies, 114 patients, I2 = 85%). Conclusion In patients with Fabry disease, enzyme replacement therapy was associated with stabilization of LVM, MLVWT, and T1 mapping values, whereas LGE extent mildly increased. Keywords: Fabry Disease, Enzyme Replacement Therapy (ERT), Cardiac MRI, Late Gadolinium Enhancement (LGE) Supplemental material is available for this article. © RSNA, 2024.

Fabry-specific treatment in Australia: time to align eligibility criteria with international best practices

BACKGROUND

Disease-specific therapy aims to improve symptoms, stabilise current disease and delay progression in patients with Fabry disease. In Australia, treatment access is subject to eligibility criteria initially established in 2004. Patients and their clinicians question why these criteria have remained unchanged despite significant progress in disease understanding.

AIMS

Appraise the clinical quality of the Australian treatment access criteria.

METHODS

The Fabry Australia Medical Advisory Committee (N = 6) used the Appraisal of Guidelines for REsearch and Evaluation Global Rating Scale (AGREE II GRS) to assess the clinical quality of the current treatment eligibility criteria. They reviewed the literature, developed 17 clinical statements to help guide reforms of the eligibility criteria and achieved consensus (achievement of ≥75% agreement in the range 5-7 on a 7-point Likert scale) through anonymous voting. The findings were applied to develop proposals for revised classification and treatment initiation criteria.

RESULTS

The current treatment eligibility criteria underperformed on the AGREE II GRS. They are pragmatic but out-of-step with contemporary data. Consensus was achieved on all 17 proposed clinical statements. There was strong agreement to differentiate classical male Fabry patients to facilitate timelier access to Fabry-specific treatment. There was also agreement on the value of adopting relevant organ involvement criteria in classical female patients and patients with non-classical disease.

CONCLUSIONS

Australian access criteria are misaligned with current clinical evidence. The clinical statements and proposed classification and initiation criteria should prompt discussions to support more equitable access to treatment and better align Australian practice with contemporary evidence and international guidelines.

Pathophysiology of cerebral small vessel disease: a journey through recent discoveries

Cerebral small vessel disease (cSVD) encompasses a heterogeneous group of age-related small vessel pathologies that affect multiple regions. Disease manifestations range from lesions incidentally detected on neuroimaging (white matter hyperintensities, small deep infarcts, microbleeds, or enlarged perivascular spaces) to severe disability and cognitive impairment. cSVD accounts for approximately 25% of ischemic strokes and the vast majority of spontaneous intracerebral hemorrhage and is also the most important vascular contributor to dementia. Despite its high prevalence and potentially long therapeutic window, there are still no mechanism-based treatments. Here, we provide an overview of the recent advances in this field. We summarize recent data highlighting the remarkable continuum between monogenic and multifactorial cSVDs involving NOTCH3, HTRA1, and COL4A1/A2 genes. Taking a vessel-centric view, we discuss possible cause-and-effect relationships between risk factors, structural and functional vessel changes, and disease manifestations, underscoring some major knowledge gaps. Although endothelial dysfunction is rightly considered a central feature of cSVD, the contributions of smooth muscle cells, pericytes, and other perivascular cells warrant continued investigation.

Potential Usefulness of Lifetime Globotriaosylsphingosine Exposure at Diagnosis and Baseline Modified Disease Severity Score in Early-Diagnosed Patients With Fabry Disease

BACKGROUND

Fabry disease (FD) is a lysosomal storage disease caused by a deficit of α-galactosidase A (GAL). Recently, plasma globotriaosylsphingosine (lyso-Gb3), a pathogenic analog of a substrate of GAL, has been suggested as a potential biomarker for FD, and disease severity scores, such as the Mainz Severity Score Index (MSSI), the Disease Severity Scoring System (DS3), and FASTEX (FAbry STabilization indEX), are useful tools for evaluating the severity of signs and symptoms in symptomatic FD patients. However, a more useful method of evaluating disease severity in early-diagnosed FD patients such as children, adult females, and asymptomatic patients is needed. Here, we proposed modified MSSI and DS3 scores to which we added phenotype, urinary mulberry bodies, and history of past pain attacks and examined the clinical usefulness of lyso-Gb3 and modified scores for early-diagnosed FD patients.

RESULT

In 13 early-diagnosed FD patients, we developed modified MSSI and DS3 scores and examined the correlation of lifetime lyso-Gb3 exposure at diagnosis with the conventional or modified scores. Lifetime lyso-Gb3 exposure was positively correlated only with the modified DS3 score. Additionally, we examined the long-term changes in plasma lyso-Gb3 concentration and in conventional MSSI, DS3, and FASTEX. In males, plasma lyso-Gb3 concentration decreased more rapidly than in females. In all patients, the severity scores were mild and remained nearly stable throughout the follow-up period.

CONCLUSION

Our data suggest that lifetime lyso-Gb3 exposure and the modified DS3 score are useful in early-diagnosed patients.

Updated Evaluation of Agalsidase Alfa Enzyme Replacement Therapy for Patients with Fabry Disease: Insights from Real-World Data

The clinical use of agalsidase alfa as enzyme replacement therapy (ERT) for Fabry disease (FD) has spread since 2001, and a large body of evidence of its effectiveness has been collected. This review presents the clinical and laboratory results achieved with agalsidase alfa, which has been published in the literature. Agalsidase alfa infusion slows down or stops the progression of renal damage, expressed by reduction or stabilization of the annual decline of the glomerular filtration rate; yearly decrease of glomerular filtration rate (slope) sometimes is reduced until its stabilization. ERT prevents or reduces the occurrence of hypertrophic cardiomyopathy or slows the increase over time if it is already present. Moreover, regarding neurological manifestations, ERT improves neuropathic pain and quality of life, and recent data indicated that it may also prevent the burden of cerebrovascular disease. In addition to ERT's clinical benefits, crucial topics like the most appropriate time to start therapy and the role of anti-drug antibodies (ADA) are analyzed. Treatment with agalsidase alfa in patients with FD substantially improves their outcomes and enhances their quality of life in patients with FD.

Comorbidity of patients with noncommunicable diseases in general practice. Eurasian guidelines

Создание руководства поддержано Советом по терапевтическим наукам отделения клинической медицины Российской академии наук.

Clinical staging of Anderson-Fabry cardiomyopathy: An operative proposal

As a slowly progressive form of hypertrophic cardiomyopathy (HCM), Anderson-Fabry disease (FD) resembles the phenotype of the most common sarcomeric forms, although significant differences in presentation and long-term progression may help determine the correct diagnosis. A variety of electrocardiographic and imaging features of FD cardiomyopathy have been described at different times in the course of the disease, and considerable discrepancies remain regarding the assessment of disease severity by individual physicians. Therefore, we here propose a practical staging of FD cardiomyopathy, in hopes it may represent the standard for cardiac evaluation and facilitate communication between specialized FD centres and primary care physicians. We identified 4 main stages of FD cardiomyopathy of increasing severity, based on available evidence from clinical and imaging studies: non-hypertrophic, hypertrophic - pre-fibrotic, hypertrophic - fibrotic, and overt dysfunction. Each stage is described and discussed in detail, following the principle that speaking a common language is critical when managing such complex patients in a multi-disciplinary and sometimes multi-centre setting.

Prevalence of Fabry disease and GLA variants in young patients with acute stroke: The challenge to widen the screening. The Fabry-Stroke Italian Registry

BACKGROUND

Fabry disease (FD) is a treatable X-linked lysosomal storage disorder caused by GLA gene variants leading to alpha-galactosidase A deficiency. FD is a rare cause of stroke, and it is still controversial whether in stroke patients FD should be searched from the beginning or at the end of the diagnostic workup (in cryptogenic strokes).

METHODS

Fabry-Stroke Italian Registry is a prospective, multicentric screening involving 33 stroke units. FD was sought by measuring α-galactosidase A activity (males) and by genetic tests (males with reduced enzyme activity and females) in patients aged 18-60 years hospitalized for TIA, ischemic stroke, or intracerebral hemorrhage. We diagnosed FD in patients with 1) already known pathogenic GLA variants; 2) novel GLA variants if additional clinical, laboratory, or family-derived criteria were present.

RESULTS

Out of 1906 patients, we found a GLA variant in 15 (0.79%; 95%CI 0.44-1.29) with a certain FD diagnosis in 3 (0.16%; 95%CI 0.03-0.46) patients, none of whom had hemorrhage. We identified 1 novel pathogenic GLA variant. Ischemic stroke etiologies in carriers of GLA variants were: cardioaortic embolism (33%), small artery occlusion (27%), other causes (20%), and undetermined (20%). Mild severity, recurrence, previous TIA, acroparesthesias, hearing loss, and small artery occlusion were predictors of GLA variant.

CONCLUSION

In this large multicenter cohort the frequency of FD and GLA variants was consistent with previous reports. Limiting the screening for GLA variants to patients with cryptogenic stroke may miss up to 80% of diagnoses. Some easily recognizable clinical features could help select patients for FD screening.

Fatigue as hallmark of Fabry disease: role of bioenergetic alterations

Fabry disease (FD) is a lysosomal storage disorder due to the impaired activity of the α-galactosidase A (GLA) enzyme which induces Gb3 deposition and multiorgan dysfunction. Exercise intolerance and fatigue are frequent and early findings in FD patients, representing a self-standing clinical phenotype with a significant impact on the patient's quality of life. Several determinants can trigger fatigability in Fabry patients, including psychological factors, cardiopulmonary dysfunctions, and primary alterations of skeletal muscle. The "metabolic hypothesis" to explain skeletal muscle symptoms and fatigability in Fabry patients is growing acknowledged. In this report, we will focus on the primary alterations of the motor system emphasizing the role of skeletal muscle metabolic disarrangement in determining the altered exercise tolerance in Fabry patients. We will discuss the most recent findings about the metabolic profile associated with Fabry disease offering new insights for diagnosis, management, and therapy.

Impact of Nontreatment Duration and Keratopathy on Major Adverse Cardiovascular Events in Fabry Disease: A Nationwide Cohort Study

Fabry disease (FD) is a rare inherited X-linked lysosomal storage disorder that results in the progressive accumulation of glycosphingolipids in multiple organs. Early FD-specific treatments may improve clinical outcomes; however, clinical evidence about early FD treatment is limited. We aimed to determine the cardiovascular outcomes of patients with FD who received enzyme replacement therapy. This nationwide observational study was conducted using the National Health Claims database of the Korean population with FD. The primary outcome was major adverse cardiovascular events (MACEs). MACE risk factors in FD were evaluated using time-dependent Cox regression. Between January 2007 and April 2022, 188 patients with FD were analyzed. Among them, 22 (11.7%) experienced MACE (males: 14/95 [14.7%]; females: 8/93 [8.6%]). The mean age at MACE diagnosis was 53.5 ± 11.0 years in all patients with FD, which was lower in males compared with in females (49.7 ± 9.6 vs. 60.0 ± 10.7 years, p = 0.030). Multivariate analysis (HR, 95% CI) revealed that age (1.042; 1.004-1.082) and duration of FD nontreatment (1.040; 1.003-1.078) were significant MACE risk factors in all patients. In males, age (1.080; 1.032-1.131), FD nontreatment duration (1.099; 1.048-1.152), and keratopathy (18.920; 4.174-85.749) were significant MACE risk factors in multivariate analysis. In females, the only significant MACE risk factor was a high Charlson comorbidity index score (1.795; 1.229-2.622). In conclusion, duration of FD nontreatment and keratopathy are significant MACE risk factors in males with FD. These findings suggest the importance of early initiation of FD-specific treatment and careful evaluation of keratopathy in males with FD.

Fabry App: the value of a portable technology in recording day-to-day patient monitored information in patients with Fabry disease

BACKGROUND

Fabry disease is a rare inherited disorder resulting from deficient α-galactosidase A enzyme activity. Common disease manifestations are sweating abnormalities, neuropathic pain, gastrointestinal symptoms and fatigue. Challenges are faced by health care professionals in evaluating symptom burden in the current clinical setting, and the demand for alternative methods for monitoring disease-specific symptoms has seen an acceleration in recent years. Smartphone technologies offer the potential for continuity of care and surveillance. As a part of a quality improvement project, a disease specific app was developed in collaboration with a software company (Health Touch Ltd) and made available for patient use in May 2018. The Fabry mobile app records five categories: pain, gastrointestinal symptoms, sweating, activity levels, medications. Fabry disease patients with gastrointestinal and pain symptoms attending the Lysosomal Storage Disorders Unit of the Royal Free London NHS Foundation Trust were reviewed to assess eligibility and invited to download the app for recording their symptoms (activity, sweating, pain and gastrointestinal) and medications. Patient-generated data were transmitted to a secure website for clinicians to review.

RESULTS

One-hundred and thirty-nine symptomatic Fabry disease patients who had a smartphone (iPhone or android) were invited to download the app. Sixty-seven patients (26 males and 41 females; median age, 49 years [range, 20-81]) downloaded and tracked the Fabry App at least once. The median frequency of use per patient was 6 (range, 1-629). Pain in the hands and abdominal pain were significantly higher (p = 0.009 and p = 0.007, respectively) in patients with classic phenotype compared with patients with non-classic phenotypes.

CONCLUSIONS

We demonstrated the feasibility and acceptability of a smartphone app to facilitate the remote assessment and monitoring of Fabry disease symptom burden on a daily/weekly basis, as an alternative to the current standard of care that requires patients to recall their symptoms during 6 to 12 monthly annual clinic visits. Patients who were more likely to use the app had greater disease burden. This innovation has the potential to assess disease progression, early therapeutic intervention, thereby decreasing the burden of morbidity and mortality among Fabry patients, and to record long-term effects of Fabry-specific therapies.

The Importance of Early Treatment of Inherited Neuromuscular Conditions

There has been tremendous progress in treatment of neuromuscular diseases over the last 20 years, which has transformed the natural history of these severely debilitating conditions. Although the factors that determine the response to therapy are many and in some instance remain to be fully elucidated, early treatment clearly has a major impact on patient outcomes across a number of inherited neuromuscular conditions. To improve patient care and outcomes, clinicians should be aware of neuromuscular conditions that require prompt treatment initiation. This review describes data that underscore the importance of early treatment of children with inherited neuromuscular conditions with an emphasis on data resulting from newborn screening efforts.

Fabry disease - what a gastroenterologist should know

Fabry disease is a rare, X-linked metabolic error caused by various mutations in the α-galactosidase A gene, which results in the accumulation of glycosphingolipids. Gastrointestinal symptoms are quite common in affected patients; therefore, it is important for gastroenterologists to keep it in mind as a differential diagnosis for especially challenging patients. The following review provides concise information on epidemiology and genetics, signs, and symptoms of the disease, focusing on the gastrointestinal (GI) tract, providing a brief overview of the diagnostic process and the available treatment, both disease specific and supportive, again with a focus on alleviation of gastrointestinal symptoms.

Fabry Disease: More than a Phenocopy of Hypertrophic Cardiomyopathy

Fabry disease (FD) is a genetic lysosomal storage disease with frequent cardiovascular involvement, whose presence is a major determinant of adverse clinical outcomes. As a potentially treatable cause of left ventricular hypertrophy (LVH) and heart failure with preserved ejection fraction, the early recognition of FD is crucial to initiate enzyme replacement therapy and improve long-term prognosis. Multimodality imaging plays a central role in the evaluation of patients with FD and helps in the differential diagnosis of other conditions presenting with LVH. In the present review, we explore the current applications of multimodality cardiac imaging, in particular echocardiography and cardiovascular magnetic resonance, in the diagnosis, prognostic assessment, and follow-up of patients with FD.

Impact of enzyme replacement therapy and migalastat on left atrial strain and cardiomyopathy in patients with Fabry disease

Aims

Cardiomyopathy in Fabry disease (FD) is a major determinant of morbidity and mortality. This study investigates the effects of FD-specific treatment using enzyme replacement therapy (ERT) and chaperone therapy on left atrial (LA) function using two-dimensional speckle tracking echocardiography (2DSTE).

Methods and results

In this prospective observational single-center study, 20 FD patients [10 (50%) females] treated with migalastat, 48 FD patients [24 (50%) females] treated with ERT (agalsidase-alfa and agalsidase-beta), and 30 untreated FD patients (all females) as controls were analyzed. The mean follow-up time ranged from 26 to 81 months. 2DSTE was performed for left ventricle strain, right ventricle strain, and LA strain (LAS). FD-specific treated patients presented with increased left ventricular mass index (LVMi) and higher frequency of left ventricular hypertrophy at baseline, whereas untreated control patients showed normal baseline values. FD-specific treated (including migalastat and ERT) patients showed stabilization of LAS over time (p > 0.05). LVMi was also stable in treated FD patients during observation (p > 0.05).

Conclusion

In patients with FD, treated with either ERT or chaperone therapy, LAS values measured by echocardiographic speckle tracking were stable over time, pointing toward disease stabilization.

Genotype-Phenotype Correlations in 293 Russian Patients with Causal Fabry Disease Variants

BACKGROUND

Fabry disease (FD) is a rare hereditary multisystem disease caused by variants of the GLA gene. Determination of GLA gene variants and identification of genotype-phenotype correlations allow us to explain the features of FD associated with predominant damage of one or another system, both in the classical and atypical forms of FD, as well as in cases with late manifestation and involvement of one of the systems.

METHODS

The study included 293 Russian patients with pathogenic variants of the GLA gene, which were identified as a result of various selective screening programs. Screening was carried out for 48,428 high-risk patients using a two-step diagnostic algorithm, including the determination of the concentration of the biomarker lyso-Gb3 as a first-tier test. Screening of atypical FD among patients with HCM was carried out via high-throughput sequencing in another 2427 patients.

RESULTS

102 (0.20%) cases of FD were identified among unrelated patients as a result of the study of 50,855 patients. Molecular genetic testing allowed us to reveal the spectrum and frequencies of 104 different pathogenic variants of the GLA gene in 293 examined patients from 133 families. The spectrum and frequencies of clinical manifestations in patients with FD, including 20 pediatric patients, were described. Correlations between the concentration of the lyso-Gb3 biomarker and the type of pathogenic variants of the GLA gene have been established. Variants identified in patients with early stroke were described, and the association of certain variants with the development of stroke was established.

CONCLUSIONS

The results of a large-scale selective FD screening, as well as clinical and molecular genetic features, in a cohort of 293 Russian patients with FD are described.

Clinical significance of small nerve fiber involvement in the early diagnosis and treatment of patients with Fabry disease

INTRODUCTION

Peripheral nervous system is early involved in Fabry disease (FD) and preferentially the small nerve fibers, causing the characteristic neuropathic pain crises usually beginning in childhood. Early detection of this likely underdiagnosed disease is an important approach because causal therapies are available.

METHODS

We conducted a case-series study to investigate the small nerve fiber involvement in FD and its contribution to the diagnosis of the disease but also to the timely effective therapy administration. We used specific structured scales of symptoms and signs to detect peripheral neuropathy, as well as suitable functional and structural tests to diagnose the small fiber neuropathy (SFN).

RESULTS

Twenty-seven consecutive patients (14 men, mean age 44.62 ± 10.70 years) with suspected FD were included in this study. Most of the patients presented symptoms of small nerve fiber involvement, which were accompanied by abnormal test results, fulfilling the criteria for SFN. The detection of SFN in our patients allowed the completion of the FD diagnostic criteria and thus the initiation of therapy. In five patients the SFN diagnosis determined the administration of therapy, whereas in two others it might be considered.

CONCLUSION

Our results further suggest the importance of early diagnosis of peripheral neuropathy, especially of small nerve fiber involvement, in patients with suspected FD as it contributes crucially not only to the diagnosis but also to the timely effective initiation of FD therapy.

Prognostic Implications of the Extent of Cardiac Damage in Patients With Fabry Disease

BACKGROUND

There is limited evidence on the risk stratification of cardiovascular outcomes in patients with Fabry disease (FD).

OBJECTIVES

This study sought to classify FD patients into disease stages, based on the extent of the cardiac damage evaluated by echocardiography, and to assess their prognostic impact in a multicenter cohort.

METHODS

Patients with FD from 5 Italian referral centers were categorized into 4 stages: stage 0, no cardiac involvement; stage 1, left ventricular (LV) hypertrophy (LV maximal wall thickness >12 mm); stage 2, left atrium (LA) enlargement (LA volume index >34 mL/m2); stage 3, ventricular impairment (LV ejection fraction <50% or E/e' ≥15 or TAPSE <17 mm). The study endpoint was the composite of all-cause death, hospitalization for heart failure, new-onset atrial fibrillation, major bradyarrhythmias or tachyarrhythmias, and ischemic stroke.

RESULTS

A total of 314 patients were included. Among them, 174 (56%) were classified as stage 0, 41 (13%) as stage 1, 57 (18%) as stage 2 and 42 (13%) as stage 3. A progressive increase in the composite event rate at 8 years was observed with worsening stages of cardiac damage (log-rank P < 0.001). On multivariable Cox regression analysis, the staging was independently associated with the risk of cardiovascular events (HR: 2.086 per 1-stage increase; 95% CI: 1.487-2.927; P < 0.001). Notably, cardiac staging demonstrated a stronger and additive prognostic value, as compared with the degree of LV hypertrophy.

CONCLUSIONS

In FD patients, a novel staging classification of cardiac damage, evaluated by echocardiography, is strongly associated with cardiovascular outcomes and may be helpful to refine risk stratification.

Genetic and phenotypic profile of Fabry disease in the population of Vale do Paraiba and Eastern São Paulo

INTRODUCTION

Fabry disease (FD) is an inborn error of metabolism characterized by α-galactosidase A deficiency. The primary objective was to evaluate the genetic and phenotypic profile of Fabry disease in hemodialysis.

METHODS

Observational cohort study to determine the incidence of genetic variations and phenotypic changes for FD in hemodialysis patients in the Paraiba Valley and Eastern São Paulo. Genetic testing for the GLA gene was performed for men and women over 12 years of age at the hemodialysis clinics between January 2016 and December 2019 as a screening protocol.

RESULTS

The cases came from screening exams of the index case among patients with chronic kidney disease, resulting in 17 families and totaling 82 patients under study. The classification of the most prevalent variant was that of uncertain significance (54%), followed by the pathogenic variant (46%). Five patients in two families were described with two types of variants not previously described in the literature, with pathogenic behavior. Comparing the types of variants, the presence of a pathogenic variant was associated with higher levels of lysoGB3, lower values for alpha-GAL activity and higher frequency of symptoms related to FD.

CONCLUSION

We characterized an extensive population of patients with FD variants with rich genetic, clinical and biomarker details. We believe that this study can help to better characterize the Brazilian population with FD and the most frequent types of variants.

A questionnaire survey on the diagnosis and treatment of Fabry nephropathy in clinical practice

BACKGROUND

Fabry nephropathy is characterized by a deficiency of lysosomal alpha-galactosidase A, which results in proteinuria and kidney disease. The ineffectiveness of enzyme replacement therapy (ERT) for severe kidney failure highlights the need for early detection and meaningful markers. However, because the diagnosis and treatment of Fabry disease can vary according to the expertise of physicians, we evaluated the opinions of Korean specialists.

METHODS

A questionnaire regarding the management of Fabry nephropathy was emailed to healthcare providers with the experience or ability to treat individuals with Fabry nephropathy.

RESULTS

Of the 70 experts who responded to the survey, 43 were nephrologists, and 64.3% of the respondents reported having treated patients with Fabry disease. Pediatricians are treating primarily patients with classic types of the disease, while nephrologists and cardiologists are treating more patients with variant types. Only 40.7% of non-nephrologists agreed that a kidney biopsy was required at the time of diagnosis, compared with 81.4% of nephrologists. Thirty-eight of 70 respondents (54.3%) reported measuring globotriaosylsphingosine (lyso-Gb3) as a biomarker. The most common period to measure lyso-Gb3 was at the time of diagnosis, followed by after ERT, before ERT, and at screening. For the stage at which ERT should begin, microalbuminuria and proteinuria were chosen by 51.8% and 28.6% of respondents, respectively.

CONCLUSION

Nephrologists are more likely to treat variant Fabry disease rather than classic cases, and they agree that ERT should be initiated early in Fabry nephropathy, using lyso-Gb3 as a biomarker.

Consensus recommendations for the treatment and management of patients with Fabry disease on migalastat: a modified Delphi study

Objective

Fabry disease is a progressive disorder caused by deficiency of the α-galactosidase A enzyme (α-Gal A), leading to multisystemic organ damage with heterogenous clinical presentation. The addition of the oral chaperone therapy migalastat to the available treatment options for Fabry disease is not yet universally reflected in all treatment guidelines. These consensus recommendations are intended to provide guidance for the treatment and monitoring of patients with Fabry disease receiving migalastat.

Methods

A modified Delphi process was conducted to determine consensus on treatment decisions and monitoring of patients with Fabry disease receiving migalastat. The multidisciplinary panel comprised 14 expert physicians across nine specialties and two patients with Fabry disease. Two rounds of Delphi surveys were completed and recommendations on the use of biomarkers, multidisciplinary monitoring, and treatment decisions were generated based on statements that reached consensus.

Results

The expert panel reached consensus agreement on 49 of 54 statements, including 16 that reached consensus in round 1. Statements that reached consensus agreement are summarized in recommendations for migalastat treatment and monitoring, including baseline and follow-up assessments and frequency. All patients with Fabry disease and an amenable mutation may initiate migalastat treatment if they have evidence of Fabry-related symptoms and/or organ involvement. Treatment decisions should include holistic assessment of the patient, considering clinical symptoms and organ involvement as well as patient-reported outcomes and patient preference. The reliability of α-Gal A and globotriaosylsphingosine as pharmacodynamic response biomarkers remains unclear.

Conclusion

These recommendations build on previously published guidelines to highlight the importance of holistic, multidisciplinary monitoring for patients with Fabry disease receiving migalastat, in addition to shared decision-making regarding treatments and monitoring throughout the patient journey. GRAPHICAL ABSTRACT.