Gastrointestinal Involvement in Anderson-Fabry Disease: A Narrative Review

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.

Diet and Physical Activity in Fabry Disease: A Narrative Review

Fabry disease (FD) is caused by mutations in the galactosidase alpha (GLA) gene which lead to the accumulation of globotriaosylceramide (Gb-3). Enzyme replacement therapy (ERT) and oral chaperone therapy are the current pharmacological treatments for this condition. However, in the literature, there is a growing emphasis on exploring non-pharmacological therapeutic strategies to improve the quality of life of patients with FD. In particular, the nutritional approach to FD has been marginally addressed in the scientific literature, although specific dietary interventions may be useful for the management of nephropathy and gastrointestinal complications, which are often present in patients with FD. Especially in cases of confirmed diagnosis of irritable bowel syndrome (IBS), a low-FODMAP diet can represent an effective approach to improving intestinal manifestations. Furthermore, it is known that some food components, such as polyphenols, may be able to modulate some pathogenetic mechanisms underlying the disease, such as inflammation and oxidative stress. Therefore, the use of healthy dietary patterns should be encouraged in this patient group. Sports practice can be useful for patients with multi-organ involvement, particularly in cardiovascular, renal, and neurological aspects. Therefore, the aim of this review is to summarize current knowledge on the role of nutrition and physical activity in FD patients.

Long-term outcomes in two adult siblings with Fucosidosis - Diagnostic odyssey and clinical manifestations

Fucosidosis (OMIN# 230000) is a rare lysosomal storage disorder (LSDs) caused by mutations in the FUCA1 gene, leading to alpha-L-fucosidase deficiency; it is inherited as an autosomal recessive trait. Fucosidosis represents a disease spectrum with a wide variety of clinical features, but most affected patients have slow neurologic deterioration. Many patients die young and the long-term clinical outcomes in adult patients are poorly documented. Here, we report the long-term follow up of two Caucasian siblings, a 31-year-old man and 25-year-old woman. We describe the clinical, biochemical, radiological and genetic findings in two siblings affected by Fucosidosis and the differences between them after 19-years follow up. The dermatological features of the younger sibling have been reported previously by Bharati et al. (2007). Both patients have typical features of Fucosidosis, such as learning difficulties, ataxia, and angiokeratomas with differing severity. Case 1 presents severe ataxia with greater limitation of mobility, multiple dysostoses, angiokeratomas on his limbs, retinal vein enlargement and increased tortuosity in the eye and gastrointestinal symptoms. Biochemical analysis demonstrated a deficiency of alpha-fucosidase in leucocytes. Case 2 has a greater number of angiokeratomas and has suffered three psychotic episodes. The diagnosis of Fucosidosis was confirmed in cultured skin fibroblast at the age of 12 years. Molecular analysis of the FUCA1 gene showed a heterozygous mutation c.998G > A p.(Gly333Asp), with a pathogenic exon 4 deletion in the other allele in both patients. Conclusion. Fucosidosis presents a wide clinical heterogeneity and intrafamilial variability of symptoms. Psychosis and gastrointestinal symptoms have not been reported previously in Fucosidosis.

Disruption of the microbiota-gut-brain axis is a defining characteristic of the α-Gal A (-/0) mouse model of Fabry disease

Fabry disease (FD) is an X-linked metabolic disease caused by a deficiency in α-galactosidase A (α-Gal A) activity. This causes accumulation of glycosphingolipids, especially globotriaosylceramide (Gb3), in different cells and organs. Neuropathic pain and gastrointestinal (GI) symptoms, such as abdominal pain, nausea, diarrhea, constipation, and early satiety, are the most frequent symptoms reported by FD patients and severely affect their quality of life. It is generally accepted that Gb3 and lyso-Gb3 are involved in the symptoms; nevertheless, the origin of these symptoms is complex and multifactorial, and the exact mechanisms of pathogenesis are still poorly understood. Here, we used a murine model of FD, the male α-Gal A (-/0) mouse, to characterize functionality, behavior, and microbiota in an attempt to elucidate the microbiota-gut-brain axis at three different ages. We provided evidence of a diarrhea-like phenotype and visceral hypersensitivity in our FD model together with reduced locomotor activity and anxiety-like behavior. We also showed for the first time that symptomology was associated with early compositional and functional dysbiosis of the gut microbiota, paralleled by alterations in fecal short-chain fatty acid levels, which partly persisted with advancing age. Interestingly, most of the dysbiotic features suggested a disruption of gut homeostasis, possibly contributing to accelerated intestinal transit, visceral hypersensitivity, and impaired communication along the gut-brain axis.

Gastrointestinal Sensory Neuropathy and Dysmotility in Fabry Disease: Presentations and Effect on Patient's Quality of Life

INTRODUCTION

Fabry disease is a rare multisystemic lysosomal disease resulting in variable manifestations of the gastrointestinal (GI), neurologic, cardiac, and renal systems. Whether GI manifestations are a result of gut dysmotility is undetermined. We aimed to explore GI manifestations in depth and their effect on patients with Fabry disease and to characterize gut motility.

METHODS

We recruited adult patients with Fabry disease reporting GI manifestations. All patients answered a battery of questionnaires covering symptom severity, GI-specific quality of life, and effects of work/productivity and underwent a wireless motility capsule test to measure pan-gut motility.

RESULTS

In 48 patients with Fabry disease, abnormal bowel habits and abdominal pain were the most common symptoms. Bloating, nausea, vomiting, and reflux were also prevalent. Neurologic manifestations were found in 95.8% of patients, along with their GI manifestations. Dysmotility was found in less than 35% of wireless motility capsule tests. Colon transit time was associated with constipation severity and Bristol Stool Scale. Several GI symptoms were associated with reduced quality of life, anxiety, and work/productivity, but not Fabry severity score.

DISCUSSION

This is the largest study of GI manifestations in patients with Fabry disease that characterizes gut motility. We found little association between GI manifestations and motility indices, suggesting that visceral hypersensitivity may be a major driver of symptoms. GI symptoms affect different aspects of patients' lives, yet are not always well-discussed or optimally managed in Fabry disease. Disease severity scores when used for therapeutic decision making do not often include GI symptoms or their impact.

Low skeletal muscle mass as an early sign in children with fabry disease

BACKGROUND & AIMS

Fabry disease (FD) is a rare X-linked metabolic storage disorder due to the deficiency of lysosomal α-galactosidase A which causes the accumulation of glycosphingolipids throughout the body. Underweight and low BMI have been occasionally reported in FD patients previously. Whether underweight is common in the early stage of FD and body composition analysis to determine the cause have not been reported.

METHODS

Children who were diagnosed with FD in the Children's Hospital of Zhejiang University School of Medicine from July 2014 to December 2022 were enrolled. Clinical data were obtained from medical records. Whole body dual energy X-ray absorptiometry scans (DXA) were used to assess body composition (fat mass, FM; fat free mass, FFM and bone mass) according to the International Society of Clinical Densitometry's standard operating method. Whole body muscle mass was calculated as fat-free mass minus bone mass. Appendicular skeletal muscle mass (ASM) was calculated as the sum of the arm and the leg muscle mass. The FM, FFM, ULSM and LLSM indices were calculated by dividing the total FM, FFM, and upper and lower limb skeletal muscle mass (ULSM and LLSM) by the height squared.

RESULTS

A total of eighteen children (14 boys and 4 girls) were enrolled. Thirteen boys had the classical phenotype, and five children (1 boy with the N215S mutation and 4 girls) had the late-onset phenotype. Seven children with the classical phenotype (53.8%) and two of the five children (40%) with the late-onset phenotype had abnormal BMIs. Sixteen of the eighteen children (88.9%) had a height in the normal range, suggesting that low BMI was mainly due to underweight. By DXA body composition analysis, the FMI was abnormal in 3 children (2 boys and 1 girl), and the FFMI was abnormal in 12 children (9 boys and 3 girls). For the classical phenotype, 2 of the 13 children (15.4%) had abnormal FMI values, while 10 (76.9%) had abnormal FFMI values. Eight patients (61.5%) with the classical phenotype had a significant reduction in muscle mass index, ASM index and LLSM index values compared with age- and sex- matched Chinese controls. Late-onset patients also had mild low skeletal muscle mass compared to controls. The results suggested that low skeletal muscle mass is common in early FD.

CONCLUSIONS

This is the first study to examine body composition and muscle mass in early Fabry disease patients. Low skeletal muscle mass is a common early symptom in children with Fabry disease, suggesting that skeletal muscle is significantly affected in the early stages of FD.

Clinical and biochemical footprints of inherited metabolic disorders. XI. Gastrointestinal symptoms

Inherited metabolic disorders presenting with gastrointestinal (GI) symptoms are characterized by the dysfunction of the esophagus, stomach, small and large intestines, and pancreas. We have summarized associations of signs and symptoms in 339 inherited metabolic diseases presenting with GI symptoms. Feeding difficulties represent the most common abnormality reported for IMDs with GI involvement (37%) followed by intestinal problems (30%), vomiting (22%), stomach and pancreas involvement (8% each), and esophagus involvement (4%). This represents the eleventh of a series of articles attempting to create and maintain a comprehensive list of clinical and metabolic differential diagnoses according to system involvement.

Gut dysmotility in children with neurological impairment: the nutritional management

Intestinal motility disorders represent a frequent problem in children with neurological impairment. These conditions are characterized by abnormal movements of the gut, which can result in symptoms such as constipation, diarrhea, reflux, and vomiting. The underlying mechanisms leading to dysmotility are various, and the clinical manifestations are often nonspecific. Nutritional management is an important aspect of care for children with gut dysmotility, as it can help to improve their quality of life. Oral feeding, when safe and in the absence of risk of ingestion or severe dysphagia, should always be encouraged. When oral nutrition is insufficient or potentially harmful, it is necessary to switch to an enteral by tube or parenteral nutrition before the onset of malnutrition. In most cases, children with severe gut dysmotility may require feeding via a permanent gastrostomy tube to ensure adequate nutrition and hydration. Drugs may be necessary to help manage gut dysmotility, such as laxatives, anticholinergics and prokinetic agents. Nutritional management of patients with neurological impairment often requires an individualized care plan to optimize growth and nutrition and to improve overall health outcomes. This review tries to sum up most significant neurogenetic and neurometabolic disorders associated with gut dysmotility that may require a specific multidisciplinary care, identifying a proposal of nutritional and medical management.

An expert consensus on practical clinical recommendations and guidance for patients with classic Fabry disease

Fabry disease is an X-linked inherited lysosomal disorder that causes accumulation of glycosphingolipids in body fluids and tissues, leading to progressive organ damage and reduced life expectancy. It can affect both males and females and can be classified into classic or later-onset phenotypes. In classic Fabry disease, α-galactosidase A (α-Gal A) activity is absent or severely reduced and disease manifestations have an early onset that can affect multiple organs. In contrast, in later-onset Fabry disease, patients have residual α-Gal A activity and clinical features are primarily confined to the heart. Individualized therapeutic goals in Fabry disease are required due to varying phenotypes and patient characteristics, and the wide spectrum of disease severity. An international group of expert physicians convened to discuss and develop practical clinical recommendations for disease- and organ-specific therapeutic goals in Fabry disease, based on expert consensus and evidence identified through a structured literature review. Biomarkers reflecting involvement of various organs in adult patients with classic Fabry disease are discussed and consensus recommendations for disease- and organ-specific therapeutic goals are provided. These consensus recommendations should support the establishment of individualized approaches to the management of patients with classic Fabry disease by considering identification, diagnosis, and initiation of disease-specific therapies before significant organ involvement, as well as routine monitoring, to reduce morbidity, optimize patient care, and improve patient health-related quality of life.

Early renal failure in childhood in a male with Fabry disease

Fabry disease is an X-linked lysosomal storage disorder caused by reduced activity or absence of the alpha-galactosidase A enzyme resulting in systemic accumulation of glycosphingolipids. End-stage renal disease (ESRD) is a late-stage manifestation of Fabry disease, typically presenting in the fifth decade of life, but is very rare in childhood. Here we present a case of an 11-year-old boy with classical Fabry disease presenting with ESRD requiring haemodialysis and transplant. Diagnosis was confirmed by renal biopsy, GLA mutation and low alpha-galactosidase A levels. He has an unusual genotype, hemizygous for the c.1000-11T>A intronic variant and positive for the pseudodeficiency allele D313Y. Due to the possibility of very early and accelerated disease progression, Fabry disease should be considered as a possible diagnosis in unexplained renal failure in males from a younger age.