Anderson-Fabry's disease: alpha-galactosidase deficiency

Neuropsychiatric Symptoms and Their Association With Sex, Age, and Enzyme Replacement Therapy in Fabry Disease: A Systematic Review

Patients suffering from Fabry disease (FD) have an increased risk of developing neuropsychiatric symptoms (NPS), mostly impairment in cognitive performance and depression. Single cases of psychosis have been reported, however, their association with FD can be coincidental. Furthermore, deficits in social functioning and adaptation as well as specific coping styles in FD patients were observed. Recent studies focused on a longitudinal course of the disease and identified risk factors associated with specific NPS. Since 2001, enzyme replacement therapy (ERT) has been available and in preliminary studies seems to improve cognitive impairment and adaptive skills. In this systematic review, we analyze the available literature on the NPS in FD and investigate if there are any differences in their distribution between males and females, children/adolescents and adults, and individuals treated with ERT and untreated. We discuss the role of the psychological, environmental, and molecular alterations and their correlation to psychiatric manifestations in FD. Finally, we would like to increase awareness of the spectrum of NPS in FD.

Reversal of the Inflammatory Responses in Fabry Patient iPSC-Derived Cardiovascular Endothelial Cells by CRISPR/Cas9-Corrected Mutation

The late-onset type of Fabry disease (FD) with GLA IVS4 + 919G > A mutation has been shown to lead to cardiovascular dysfunctions. In order to eliminate variations in other aspects of the genetic background, we established the isogenic control of induced pluripotent stem cells (iPSCs) for the identification of the pathogenetic factors for FD phenotypes through CRISPR/Cas9 genomic editing. We adopted droplet digital PCR (ddPCR) to efficiently capture mutational events, thus enabling isolation of the corrected FD from FD-iPSCs. Both of these exhibited the characteristics of pluripotency and phenotypic plasticity, and they can be differentiated into endothelial cells (ECs). We demonstrated the phenotypic abnormalities in FD iPSC-derived ECs (FD-ECs), including intracellular Gb3 accumulation, autophagic flux impairment, and reactive oxygen species (ROS) production, and these abnormalities were rescued in isogenic control iPSC-derived ECs (corrected FD-ECs). Microarray profiling revealed that corrected FD-derived endothelial cells reversed the enrichment of genes in the pro-inflammatory pathway and validated the downregulation of NF-κB and the MAPK signaling pathway. Our findings highlighted the critical role of ECs in FD-associated vascular dysfunctions by establishing a reliable isogenic control and providing information on potential cellular targets to reduce the morbidity and mortality of FD patients with vascular complications.

Symptoms and Quality of Life in Patients with Fabry Disease: Results from an International Patient Survey

INTRODUCTION

Fabry disease is an X-linked lysosomal storage disorder caused by a deficiency of α-galactosidase A. Symptoms include neuropathic pain and gastrointestinal problems, such as diarrhoea. To inform and support the design of a Phase III clinical trial for a new oral treatment for Fabry disease, this study evaluated patients' experiences of Fabry disease symptoms, the impact of symptoms on their quality of life, and their views on participating in clinical trials.

METHODS

An online survey questionnaire was distributed to patients with Fabry disease, through relevant patient organisations. The questionnaire consisted mainly of quantitative, closed questions with pre-defined response options. Fabry-specific pain intensity and its impact on quality of life were rated on a scale from 0 to 10.

RESULTS

In total, 367 patients completed the survey, of whom half reported frequent pain, moderate to severe pain, and pain in their hands and feet. Pain frequency, intensity and location were similar for males and females. There was no clear association between Fabry-specific pain and the use of enzyme replacement therapy (ERT), with moderate to severe pain reported by 80.4% of participants receiving ERT and by 75.0% of participants not receiving ERT. Of participants who were receiving ERT, 35.7% said they were willing to discontinue it to take part in a clinical trial testing a new oral drug for treating Fabry disease. Gastrointestinal symptoms were more heterogeneous in nature and frequency than Fabry-specific pain, but still affected a significant proportion of participants.

CONCLUSIONS

Both male and female patients with Fabry disease experience significant Fabry-specific pain, which affects their quality of life. Furthermore, frequent diarrhoea affects many patients. The symptoms occur independently of the use of ERT. This suggests the healthcare needs of patients with Fabry disease are not being fully met, and additional treatments are required to improve symptoms and quality of life.

FUNDING

This study was sponsored by Actelion Pharmaceuticals Ltd. Study sponsorship was transferred to Idorsia Pharmaceuticals Ltd in July 2018.

Monogenic, Polygenic, and MicroRNA Markers for Ischemic Stroke

Ischemic stroke (IS) is a leading disease with high mortality and disability, as well as with limited therapeutic window. Biomarkers for earlier diagnosis of IS have long been pursued. Family and twin studies confirm that genetic variations play an important role in IS pathogenesis. Besides DNA mutations found previously by genetic linkage analysis for monogenic IS (Mendelian inheritance), recent studies using genome-wide associated study (GWAS) and microRNA expression profiling have resulted in a large number of DNA and microRNA biomarkers in polygenic IS (sporadic IS), especially in different IS subtypes and imaging phenotypes. The present review summarizes genetic markers discovered by clinical studies and discusses their pathogenic molecular mechanisms involved in developmental or regenerative anomalies of blood vessel walls, neuronal apoptosis, excitotoxic death, inflammation, neurogenesis, and angiogenesis. The possible impact of environment on genetics is addressed as well. We also include a perspective on further studies and clinical application of these IS biomarkers.

[Fabry's disease: Neurological disorders]

The paper considers the pathogenesis and clinical features of Fabry's disease. It is stressed that along with cardiovascular system damage and kidney injury, there are peripheral and central nervous system lesions in this disease. In Fabry's disease, great attention is paid to cerebrovascular diseases that frequently give rise to disability. Peripheral neuropathy is mainly due to involvement of minor fibers and autonomic disorders. Signs that allow this disease to be diagnosed are given.

Acidic α-galactosidase is the most abundant nectarin in floral nectar of common tobacco (Nicotiana tabacum)

BACKGROUND AND AIMS

To date, most floral nectarins (nectar proteins) are reported to function in nectar defence, particularly for insect-pollinated outcrossing species. We compared nectarin composition and abundance in selfing common tobacco (Nicotiana tobaccum) with outcrossing ornamental tobacco plants to elucidate the functional difference of nectarins in different reproductive systems.

METHODS

Common tobacco (CT) nectarins were separated by SDS-PAGE and the N terminus of the most abundant nectarin was sequenced via Edman degradation. The full-length nectarin gene was amplified and cloned from genomic DNA and mRNA with hiTail-PCR and RACE (rapid amplification of cDNA ends), and expression patterns were then investigated in different tissues using semi-quantitative reverse transcriptase PCR. Additionally, high-performance liquid chromatography and enzymatic analyses of nectar sugar composition, and other biochemical traits and functions of the novel nectarin were studied.

KEY RESULTS

The most abundant nectarin in CT nectar is an acidic α-galactosidase, here designated NTα-Gal. This compound has a molecular mass of 40 013 Da and a theoretical pI of 5·33. NTα-Gal has a conserved α-Gal characteristic signature, encodes a mature protein of 364 amino acids and is expressed in different organs. Compared with 27 other melliferous plant species from different families, CT floral nectar demonstrated the highest α-Gal activity, which is inhibited by d-galactose. Raffinose family oligosaccharides were not detected in CT nectar, indicating that NTα-Gal does not function in post-secretory hydrolysis. Moreover, tobacco plant fruits did not develop intact skin with galactose inhibition of NTα-Gal activity in nectar, suggesting that NTα-Gal induces cell-wall surface restructuring during the initial stages of fruit development.

CONCLUSIONS

α-Gal was the most abundant nectarin in selfing CT plants, but was not detected in the nectar of strictly outcrossing sister tobacco species. No function was demonstrated in antimicrobial defence. Therefore, floral nectarins in selfing species maintain their functional significance in reproductive organ development.

Modelling the resource implications of managing adults with Fabry disease in Italy

AIMS

This study estimated the resource implications and budget impact of managing adults with Fabry disease in Italy, from the perspective of the Servizio Sanitario Nazionale (SSN).

METHODS

A decision model was constructed using published clinical outcomes and clinician-derived resource utilisation estimates depicting the management of adults with Fabry disease in Italy.

RESULTS

The expected annual cost of managing 220 existing and 20 new Fabry patients in Italy was estimated to be €28·3 million. In an average year, patients receiving enzyme replacement therapy (ERT) with 0·2 mg kg(-1) agalsidase alfa (Replagal; Shire Human Genetic Therapies, Basingstoke, Hampshire, UK) or 1·0 mg kg(-1) agalsidase beta (Fabrazyme; Genzyme Europe BV, Naarden, The Netherlands) are collectively expected to make 4500 hospital attendances to a day ward for infusions, which equates to 2000 eight-h days on the day ward associated with ERT. If all ERT-treated patients received their infusions at home, there would be a marginal reduction in the annual health care cost to manage these patients, and the total annual number of days on the day ward associated with ERT in the second year could potentially be reduced from a mean 2000 to zero, thereby releasing substantial hospital resources for use by non-Fabry patients. Currently, only agalsidase alfa is licensed for home treatment in Italy; hence, only patients receiving this enzyme could be offered home treatment.

CONCLUSION

Use of agalsidase alfa (0·2 mg kg(-1) ) instead of agalsidase beta (1·0 mg kg(-1)) has the potential to reduce health care costs and release hospital resources in different specialities for alternative use by non-Fabry patients, thereby improving the efficiency of the public health care system in Italy.

Modelling the resource implications of managing adults with Fabry disease in Norway favours home infusion

BACKGROUND

The aim of this study was to estimate the resource implications and budget impact of managing adults with Fabry disease in Norway, from the perspective of the publicly funded healthcare system.

METHODS

A decision model was constructed using published clinical outcomes and clinician-derived resource utilization estimates. The model was used to estimate the annual healthcare cost of managing a cohort of 64 adult Fabry patients in an average year.

RESULTS

The expected annual cost of managing 60 existing Fabry patients and four new patients in Norway each year was estimated to be NOK 55·8 million (€6·7 million). In an average year, patients receiving enzyme replacement therapy (ERT) with agalsidase alfa (Replagal(®)) at 0·2 mg kg⁻¹ or agalsidase beta (Fabrazyme(®)) at 1·0 mg kg⁻¹ are collectively expected to make 586 attendances to their family practitioner's office for their infusions, which equates to 128 eight-hour days associated with ERT. Encouraging more patients to undergo home-based infusions has substantial potential to free-up community-based resources. In comparison, the community-related benefit that can be obtained by switching from agalsidase beta (1·0 mg kg⁻¹) to agalsidase alpha (0·2 mg kg⁻¹) is marginal, and dependent on the two doses being clinically equivalent.

CONCLUSION

Maximizing the proportion of adults with Fabry disease undergoing home-based infusions has the potential to release community-based resources for alternative use by non-Fabry patients, thereby improving the efficiency of the publicly funded healthcare system in Norway.

Ocular manifestations of Fabry disease within in a single kindred

BACKGROUND

Fabry disease is an X-linked lysosomal storage disorder that causes progressive complications within the kidneys, brain, and heart. Ocular manifestations of this disease are often present at a very young age, thereby facilitating early diagnosis, before the signs and symptoms of renal disease, stroke, or hypertrophic cardiomyopathy. Early diagnosis by the eye care provider may eventually reduce the morbidity and mortality of this disease through the institution of therapy before the development of sclerotic end organ damage. This study evaluated 23 Fabry-affected members of a single cohort for the presence of ocular signs of Fabry disease.

METHODS

Twenty-three patients of a single family were seen on a single day. Patients were given comprehensive ophthalmic examinations and completed a health and lifestyle questionnaire.

RESULTS

Eight hemizygous men (mean age, 32.3 years) and 15 heterozygous women (mean age, 26.9 years) from a single family of 43 known Fabry patients were evaluated. Corneal verticillata was present in all patients. Additional findings in the male patients included anterior capsule opacity (25% total) and Fabry cataract (12.5%). Thinning of the retinal nerve fiber layer was observed in one man whose medical history was significant for stroke. Conjunctival and/or retinal vessel tortuosity was present in the majority of patients (62.5% and 75% of hemizygotes, respectively; 40% and 13.3% heterozygotes, respectively). Additional findings in the women included anterior capsule opacity. The majority of patients (87.5% hemizygotes, 60% heterozygotes) felt Fabry disease had an impact on their quality of life.

CONCLUSIONS

All evaluated patients who had Fabry disease had corneal verticillata, which generally does not affect vision and is readily recognizable by slit lamp examination. Greater than 60% showed conjunctival and/or retinal vessel tortuosity. The eye care provider can play a crucial role in the early recognition of ocular manifestations of Fabry disease and decrease both the time to accurate diagnosis and the delay in the institution of disease-modifying therapy.

Anderson-Fabry disease in kidneys from deceased donor

Anderson-Fabry disease (AFD) is a rare, X-linked lysosomal storage disease that leads to progressive intracellular accumulation of globotriaosylceramide in visceral organs and the vascular endothelium. We report two patients with end-stage renal disease who received renal allograft from deceased female donor who died from heart failure. A 62-year-old women received a renal allograft in July 2006. Except for low-range proteinuria, renal function was normal until 6 months after transplantation when serum creatinine increased from 120 to 150 micromol/L. A renal biopsy was performed. Based on the specific pathological finding, AFD in donor was suspected. In order to prove the diagnosis, the other recipient also underwent renal biopsy 3 months later. This was 45-year-old female with stable graft function and nonnephrotic proteinuria. Light microscopic findings included a 'foamy' appearance of affected cells with swelling and vacuolization of podocytes. Electron microscopic finding show mesangial cells and podocytes filled with dense lysosomal granules appearing as myelin figures and 'zebra bodies'. Changes were less intensive than in the biopsy of the first recipient. The donor was 54-year-old Italian women who died on the Adriatic coast after heart attack. This is the first case of AFD found in a kidney allograft from deceased donor.

Hyperhidrosis: a new and often early symptom in Fabry disease. International experience and data from the Fabry Outcome Survey

Hypohidrosis is a classic feature of Fabry disease; in contrast, hyperhidrosis has only been rarely described. The aim of the study is to characterise the baseline descriptive data on hyperhidrosis (frequency, age at onset, sex ratio and outcome with and without enzyme replacement therapy) in hemizygous male and heterozygous female patients with Fabry disease. We describe case histories of five patients with Fabry disease and hyperhidrosis seen at three different centres. We have also analysed a cohort of 21 paediatric patients in the UK and a large European cohort of patients enrolled in the Fabry Outcome Survey (FOS). Five patients (three female, two male) with hyperhidrosis were originally identified, although each had additional symptoms related to Fabry disease. The age at onset of hyperhidrosis was less than 18 years in four cases. In the cohort of 21 paediatric patients (12 female, nine male), one female had hyperhidrosis; the age at onset of this symptom was 11 years. In the FOS cohort, 66 of 714 patients with Fabry disease had hyperhidrosis (44 of 369 females, 11.9%; 22 of 345 males, 6.4%). The female predominance was observed in seven of nine countries from which data were analysed. Hyperhidrosis is an increasingly recognised feature of the Fabry disease phenotype. It is more prevalent in females than in males and often appears in childhood or adolescence. The efficacy of enzyme replacement therapy on this recently recognised symptom should be assessed.

Effects of enzyme replacement therapy on pain and health related quality of life in patients with Fabry disease: data from FOS (Fabry Outcome Survey)

BACKGROUND

Fabry disease is an X linked lysosomal storage disease caused by deficiency of the lysosomal enzyme alpha-galactosidase A. This leads to accumulation of globotriaosylceramide in nearly all tissues, including the blood vessels, kidney, myocardium, and nervous system. Symptoms often begin in childhood and include acroparaesthesia, with burning or tingling pain that spreads from the extremities to more proximal sites.

AIMS

This study set out to evaluate pain and its influence on quality of life in patients with Fabry disease receiving enzyme replacement therapy (ERT) with agalsidase alfa.

METHODS

Data were obtained from the Fabry Outcome Survey. Pain was measured using the Brief Pain Inventory (BPI), and health-related quality of life (HRQoL) was documented with the European Quality of Life Questionnaire (EQ-5D).

RESULTS

The mean (SD) score for "pain at its worst" on the BPI prior to ERT was 5.1 (2.7). One year after commencement of ERT, this had improved by 0.5, and improved by a further 0.6 after 2 years (p<0.05). Similar statistically significant improvements were seen for "pain on average" and "pain now" after 2 years of ERT. The mean HRQoL utility score prior to ERT was 0.66 (0.32). After 12 months of treatment with agalsidase alfa, this had improved to 0.74 (0.26; p<0.05); this improvement was maintained after 2 years.

CONCLUSIONS

ERT with agalsidase alfa significantly reduces pain and improves quality of life in patients with Fabry disease.

High prevalence of subclinical hypothyroidism in patients with Anderson-Fabry disease

Anderson-Fabry disease is a rare lysosomal storage disorder. It results from a deficiency of the lysosomal alpha-galactosidase A and leads to progressive accumulation of globotriaosylceramide in the endothelium and tissue cells of various organs. Some of the typical clinical findings such as tiredness, dry skin, myalgia and arthralgia as well as vague gastrointestinal complaints are also symptoms of hypothyroidism. Therefore, we studied the thyroid function in patients with Anderson-Fabry disease. Thyroid function was studied in 11 patients (6 female, 5 male) with Anderson-Fabry disease by measuring thyroid-stimulating hormone (TSH) and free thyroxine serum levels. Nine patients had chronic kidney disease with stage 1 and two with stage 5. Subclinical hypothyroidism (normal serum free thyroxine concentrations along with elevated serum TSH levels) was found in 4 of 11 patients (36.4%). Subclinical hypothyroidism was observed in both male and female patients as well as in patients with stage 1 and stage 5 kidney disease. Subclinical hypothyroidism is a common finding in patients with Anderson-Fabry disease, showing an excess prevalence as compared to the normal population. The high frequency seems to be relevant regarding the potential consequences of a hypothyroid state.

Effect of enzyme-replacement therapy on gastrointestinal symptoms in Fabry disease

Fabry disease is an X-linked recessive lysosomal storage disorder caused by deficiency of lysosomal alpha-galactosidase A. The disease affects not only kidney, myocardium, central nervous system and the skin but also, in many patients, the gastrointestinal tract. The recent advent of enzyme-replacement therapy has been reported to show beneficial effects on cardiomyopathy, renal function and autonomous nervous function. We report on a 34-year-old patient with Fabry disease in whom gastrointestinal symptoms were major complaints. Enzyme replacements led to remarkable improvement of diarrhoea and constipation. Abdominal pain, the feeling of fullness and meteorism improved, and metoclopramide, which previously had been used regularly, could be discontinued. There were also marked improvements of appetite, body weight, body mass index, physical activity and overall wellbeing. This observation should prompt further investigations into the pathophysiology of gastrointestinal manifestations in Fabry disease and the mechanisms of enzyme-replacement effects on gut function.

The expanding clinical spectrum of Anderson-Fabry disease: a challenge to diagnosis in the novel era of enzyme replacement therapy

Anderson-Fabry disease is an X-linked recessive lysosomal storage disease resulting from deficient alpha-galactosidase A activity. The conception of the disease has changed within the last decade. Studies of the last years have shown that the disease is not limited to the classical full-blown manifestation in affected males, which is well known since more than a century, but may also occur in carrier females. The phenomenology may differ in severity and kind of organ manifestation. Cardiac and renal variants with solely disease manifestation of these organs have also been described in an increasing number. It is likely that a spectrum exists regarding alpha-galactosidase A activity in both genders on the one hand, and an additional one regarding the severity and the number of organs affected on the other. The purpose of this review is to sharpen physicians' perception of this disease. Early and accurate diagnosis is mandatory considering that this disorder is now, after introduction of the novel enzyme replacement therapy, a treatable disease.

Results of an Ophthalmologic Screening Programme for Identification of Cases with Anderson-Fabry Disease

PURPOSE

Anderson-Fabry disease is an inherited lysosomal storage disease with a broad and unspecific range of symptoms, a painful course of disease and early death. The recent development of new enzyme therapy emphasises the need for early diagnosis and treatment of undiagnosed patients. One of the affected organs of Anderson-Fabry disease is the eye. Cornea verticillata--corneal opacities and corneal dystrophy--as well as tortuositas vasorum can occur in an early stage of the disease affecting almost all hemizygous men and more than 70% of heterozygous women. In order to identify unknown cases with Anderson-Fabry disease, we carried out a screening programme contacting Austrian ophthalmologists.

METHODS

All 658 Austrian ophthalmologists were asked to record patients with cornea verticillata as well as tortuositas vasorum--twice at an interval of 3 months.

RESULTS

33% of the contacted ophthalmologists replied, identifying 5 patients suspected of having Anderson-Fabry disease. After additional examinations including tests for enzyme activities Anderson-Fabry disease was confirmed in 1 man.

CONCLUSION

We have identified 1 case with Anderson-Fabry disease through our ophthalmology screening programme among a population of approximately of 8 million. Ophthalmologic screening programmes for ocular manifestations typical of Anderson-Fabry disease are limited because of the moderate visual affection in these patients. Nevertheless, considering the limited options to detect such cases otherwise, ophthalmologists have a major responsibility to identify patients with Anderson-Fabry disease on routine examinations.

Agalsidase alfa: specific treatment for Fabry disease

Fabry disease is a rare genetic lysosomal storage disorder characterized by a deficiency of the enzyme alpha-galactosidase A. The recent availability of enzyme-replacement therapy with agalsidase alfa offers specific treatment for this serious, progressive condition.