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.

Familial polycystic kidneys with no genetic confirmation: Are we sure it is ADPKD?

Autosomal dominant polycystic kidney disease (ADPKD) is the most common heritable multifocal cystic disease encountered in clinical practice, and it is usually diagnosed in patients with family history by the evidence of markedly enlarged kidneys with multiple bilateral cysts at ultrasound (U.S.), computed tomography (CT) scan, or magnetic resonance imaging (MRI). In most cases, genetic testing is not required. Though ADPKD diagnosis is often straightforward, misdiagnosis is possible. Here we present a case of ADPKD misdiagnosis, followed by a review of the most important kidney heritable multifocal cystic diseases. Our case report demonstrates that ADPKD can be erroneously diagnosed when other kidney heritable multifocal cystic diseases occur without their distinguishing manifestations and when there is no genetic characterization among the relatives. A proper diagnosis of heritable diseases is crucial, as it allows an appropriate management of family members who carry disease allele, apart from patient management. Therefore, we suggest a careful differential diagnosis with possible molecular genetic analysis in presentations with familial cystic kidneys and suspicious clinical and radiological features.

Parapelvic Cysts: An Imaging Marker of Kidney Disease Potentially Leading to the Diagnosis of Treatable Rare Genetic Disorders? A Narrative Review of the Literature.

Simple renal cysts are a common finding during abdominal imaging assessment. The incidence increases with age and it is higher in male gender. Parapelvic cysts are a subset of simple cysts that arise within the renal parenchyma, adjacent to the renal sinus, characterized by being generally single, larger, and incompletely surrounded by renal parenchyma. Noteworthy, parapelvic cysts are a rare and understudied condition which, although considered clinically insignificant due to the absence of influence on renal function, still have a controversial aetiopathogenesis. On the other hand, urological management and differential diagnosis have been thoroughly investigated. The aim of our review is to provide an overall vision on this rare condition, usually misdiagnosed and underestimated, on the basis of more recent data. An accurate differential diagnosis of parapelvic cysts can lead to the identification of treatable conditions such as Fabry disease, autosomal dominant polycystic kidney disease, polycystic liver disease and tuberous sclerosis complex disease.

Therapeutic advances in ADPKD: the future awaits.

Autosomal dominant polycystic kidney disease (ADPKD) is a heterogeneous genetic disorder included in ciliopathies, representing the fourth cause of end stage renal disease (ESRD), with an estimated prevalence between 1:1000 and 1:2500. It is mainly caused by mutations in the PKD1 and PKD2 genes encoding for polycystin 1 (PC1) and polycystin 2 (PC2), which regulate differentiation, proliferation, survival, apoptosis, and autophagy. The advances in the knowledge of multiple molecular pathways involved in the pathophysiology of ADPKD led to the development of several treatments which are currently under investigation. Recently, the widespread approval of tolvaptan and, in Italy, of long-acting release octreotide (octreotide-LAR), represents but the beginning of the new therapeutic management of ADPKD patients. Encouraging results are expected from ongoing randomized controlled trials (RCTs), which are investigating not only drugs acting on the calcium/cyclic adenosin monoposphate (cAMP) pathway, the most studied target so far, but also molecules targeting specific pathophysiological pathways (e.g. epidermal growth factor (EGF) receptor, AMP-activated protein kinase (AMPK) and KEAP1-Nrf2) and sphingolipids. Moreover, studies on animal models and cultured cells have also provided further promising therapeutic strategies based on the role of intracellular calcium, cell cycle regulation, MAPK pathway, epigenetic DNA, interstitial inflammation, and cell therapy. Thus, in a near future, tailored therapy could be the key to changing the natural history of ADPKD thanks to the vigorous efforts that are being made to implement clinical and preclinical studies in this field. Our review aimed to summarize the spectrum of drugs that are available in the clinical practice and the most promising molecules undergoing clinical, animal, and cultured cell studies.

The effects of somatostatin analogues on liver volume and quality of life in polycystic liver disease: a meta-analysis of randomized controlled trials.

A clear evidence on the benefits of somatostatin analogues (SA) on liver outcome in patients affected by polycystic liver disease is still lacking. We performed a meta-analysis of RCTs and a trial sequential analysis (TSA) evaluating the effects of SA in adult patients with polycystic liver disease on change in liver volume. As secondary outcome, we evaluated the effects on quality of life as measured by SF36-questionnaire. Six RCTs were selected with an overall sample size of 332 adult patients with polycystic liver disease (mean age: 46 years). Mean liver volume at baseline was 3289 ml in SA group and 3089 ml in placebo group. Overall, unstandardized mean difference in liver volume was - 176 ml (95%CI, - 406, 54; p < 0.133). Heterogeneity was low (I2:0%, p < 0.992). However, we performed a moderator analysis and we found that a higher eGFR significantly correlates to a more pronounced effect of SA on liver volume reduction (p = 0.036). Cumulative Z-curve in TSA did not reach either significance and futility boundaries or required information size. Three RCTs have evaluated Quality of life parameters measured by SF36-QOL questionnaire for a total of 124 patients; no significant difference was found on the effect of SA on QOL parameters when compared with placebo. The present meta-analysis revealed a potential effect of SA on reduction of liver volume and quality of life parameters, but results did not reach a statistical significance. These data could be explained by the need of further studies, as demonstrated through TSA, to reach an adequate sample size to confirm the beneficial outcomes of SAs treatment.

Stepwise shortening of agalsidase beta infusion duration in Fabry disease: Clinical experience with infusion rate escalation protocol.

BACKGROUND: Although enzyme replacement therapy with agalsidase beta resulted in a variety of clinical benefits, life-long biweekly intravenous infusion may impact on patients' quality of life. Moreover, regular infusions are time-consuming: although a stepwise shortening of infusion duration is allowed up to a minimum of 1.5 hr, in most centers it remains ≥3 hr, and no data exists about the safety and tolerability of agalsidase beta administration at maximum tolerated infusion rate. METHODS: In this study, we reported our experience with a stepwise infusion rate escalation protocol developed in our center in a cohort of 53 Fabry patients (both already receiving and treatment-naΪve), and explored factors predictive for the infusion rate increase tolerability. RESULTS: Fifty-two patients (98%) reduced infusion duration ≤3 hr; of these, 38 (72%) even reached a duration ≤2 hr. We found a significant difference between the mean duration reached by already treated and naΪve patients (p < .01). More severely affected patients (male patients and those with lower enzyme activity) received longer infusions for higher risk of infusion-associated reactions (IARs). A significant correlation between anti-agalsidase antibodies and IARs was found. CONCLUSION: Our infusion rate escalation protocol is safe and could improve patient compliance, satisfaction and quality of life.

Switch from enzyme replacement therapy to oral chaperone migalastat for treating fabry disease: real-life data.

The treatment options for Fabry disease (FD) are enzyme replacement therapy (ERT) with agalsidase alfa or beta, and the oral pharmacological chaperone migalastat. Since few data are available on the effects of switching from ERT to migalastat, we performed a single-center observational study on seven male Fabry patients (18-66 years) to assess the effects of the switch on renal, cardiac, and neurologic function, health status, pain, lyso-Gb3, α-Gal A activity and adverse effects. Data were retrospectively collected at time of diagnosis of FD (baseline, T0), and after 12 months of ERT (T1), and prospectively after 1 year of therapy with migalastat (T2). No patient died or reported renal, cardiac, or cerebrovascular events during the study period. The predefined measures for cardiac, renal and neurologic function, and FD-related symptoms and questionnaires were stable between baseline and the switch, and remained unchanged with migalastat. However, a significant improvement was observed in left ventricular mass index from baseline to T2 (p = 0.016), with a significative difference between the treatments (p = 0.028), and in median proteinuria from T2 vs T1 (p = 0.048). Moreover, scores of the BPI improved from baseline to T1, and remained stable with migalastat. Plasma lyso-Gb3 levels significantly decreased from baseline to T1 (P = 0.007) and T2 (P = 0.003), while did not significantly differ between the two treatments. α-Gal A activity increased from T0 to T2 (p < 0.0001). The frequency of adverse effects under migalastat and ERT was comparable (28% for both drugs). In conclusion, switching from ERT to migalastat is valid, safe and well tolerated.

Oral Sucrosomial® iron versus intravenous iron for recovering iron deficiency anaemia in ND-CKD patients: a cost- minimization analysis.

BACKGROUND: Oral iron is recommended as first line treatment of anemia in non-dialysis chronic kidney disease (ND-CKD) patients. Sucrosomial® iron, a new generation oral iron with high absorption and bioavailability and a low incidence of side effects, has shown to be not inferior to intravenous (IV) iron in the replacement of iron deficiency anemia in patients with ND-CKD. Besides the clinical benefit, it is also important to determine the comparative total costs of oral versus IV iron administrations. The aim of this study was to perform a cost-minimization analysis of oral Sucrosomial iron, compared with IV iron gluconate from an Italian societal perspective. METHODS: Cost analysis was performed on the 99 patients with ND-CKD and iron-deficiency anemia of the randomized trial by Pisani et al. Human and material resources utilization was recorded during each iron administration. According to study perspective, direct and indirect costs were considered. Costs for each resource unit were taken from official Italian sources. Probabilistic sensitivity analyses were carried out to test the robustness of the results. RESULTS: The base case analysis showed an average cost/cycle per patient of € 111 for oral iron and € 1302 for IV iron. Thus, the potential saving was equal to € 1191 per patient/cycle. The sensitivity analysis showed that the most sensitive driver is the time loss by patient and caregivers for the therapy and related-care, followed by the minutes of nursing care and the number of kilometres travelled to reach the referral centre. DISCUSSION: This study showed that oral Sucrosomial® iron could offer specific advantages in terms of potential savings, and allowed identifying some implications for future research. Such advantages still persist with the new single dose IV iron formulation available in the market, although to a lesser extent.

Identifying Fabry patients in dialysis population: prevalence of GLA mutations by renal clinic screening, 1995-2019.

BACKGROUND: Fabry disease (FD) is a rare X-linked genetic disorder of glycosphingolipid catabolism caused by mutations in the GLA gene. Its heterogeneous presentation, the paucity of specific early markers, and the absence of a genotype-phenotype correlation are associated with a delayed or missed diagnosis. The true prevalence of FD remains so far unknown. METHODS: A systematic search of FD screening studies in dialysis patients published from January 1995 until January 2019 was performed to reanalyze the prevalence of GLA mutations in this population after assigning their correct phenotype. RESULTS: Twenty five screening studies involving 39,621 dialysis patients were included. Of them, 116 [91 males (0.23%) and 25 females (0.06%)] were positive to the GLA sequencing analysis. 56 (48.2%) had benign variant, 52 (44.8%) a pathogenic GLA mutation (39 classic and 13 late onset mutations) and 8 (6.9%) a mutation of uncertain significance. The overall prevalence of GLA variants was 0.24% [CI 95%, 0.17-0.32] while the overall prevalence recalculated on basis of only pathogenetic mutations was 0.14% [CI 95%, 0.08-0.20]. This difference was significant (P = 0.048). CONCLUSIONS: Although the real prevalence of classic FD is low, the screening in the high-risk renal population remains of primary interest as an early diagnosis is fundamental for a timely specific therapy; moreover, the identification of index cases could allow patients' relatives to be investigated and promptly treated.

Early Biomarkers of Fabry Nephropathy: A Review of the Literature.

Progressive nephropathy is one of the main features of Fabry disease. Although some clinical signs of Fabry nephropathy are already present in childhood, patients are often diagnosed relatively late in the course of the disease due to the absence of specific clinical markers, while a timely diagnosis and the prompt start of enzyme replacement therapy may be beneficial in stabilizing renal function or slowing its decline. Proteinuria/albuminuria has been accepted as the most important marker for Fabry nephropathy; however, a large proportion of renal impairment occurs in nonalbuminuric state. Therefore, early biomarkers may be useful for early identification of kidney involvement. The aim of this article is to review the current available literature on all biomarkers of Fabry nephropathy, with a comprehensive and critical description of their utilization in early recognition of renal damage.

[Fabry's disease: a comparison of the effectiveness of two different enzyme replacement therapies]. / Malattia di Fabry: ERT a confronto.

INTRODUCTION: Anderson-Fabry disease (AFD) is a multiorgan X-linked lysosomal storage disease that particularly affects the heart, kidneys, and cerebrovascular system. Current treatment is with enzyme replacement therapy (ERT), using either beta-galactosidase ('Fabrazyme') or alpha-galactosidase ('Replagal'). From June 2009, it was recommended that patients switch to alpha-galactosidase due to a manufacturing shortage of beta-galactosidase. This study assesses the effect of switching to alpha-galactosidase on clinical outcomes in patients with AFD previously treated with beta-galactosidase. PATIENTS AND METHODS: Ten patients (seven male, three female) with genetically confirmed AFD and at least 48 months continuous data collected during treatment with beta-galactosidase 1 mg/kg every other week, were switched to alpha-galactosidase 0.2 mg/kg every other week for at least 20 months, with prospective clinical evaluations performed every 6 months. Pre-switch data was collected retrospectively from patient charts. Cardiac functional parameters were assessed using magnetic resonance imaging. RESULTS: Results showed that renal function generally remained stable after the switch. Cardiac mass had already decreased significantly (p < 0.05 vs pre-ERT) after introduction of beta-galactosidase and remained unchanged after switching to alpha-galactosidase. Symptoms of pain and health status scores did not deteriorate during alpha-galactosidase therapy. Adverse events were mostly mild and infusion -related. DISCUSSION: In conclusion, switching to alpha-galactosidse was generally well tolerated and associated with stable clinical status and preservation of both renal and cardiac function.

[Enzyme replacement therapy in patients with Fabry disease: state of the art and review of the literature]. / Terapia enzimatica sostitutiva in pazienti con malattia di Fabry.

Anderson-Fabry disease is a hereditary X-linked lysosomal storage disorder caused by a deficiency of the lysosomal enzyme alpha galactosidase A. It results in the accumulation of the glycosphingolypid globotrioasoyl ceramide (Gb3 in different cells and organs, resulting in a multi-system pathology including end organ failure. Patients with Fabry disease present clinically with cardiac, renal and neurological involvement; both life expectancy and quality of life are severely compromised. The current causal treatment for Fabry disease is enzyme replacement therapy (ERT), available since 2001. The two recombinant preparations available for ERT are agalsidase alfa (Replagal) and agalsidase beta (Fabrazyme). They have both been showed to have positive effect on kidney and heart, on the symptoms of pain and quality of life. Few data to date are available on comparison of the two preparations of ERT. This article reviews evidence of the literature and shows our personal experience about the safety and efficacy of ERT.

[Liposomial iron: a new proposal for the treatment of anaemia in chronic kidney disease]. / Il ferro liposomiale: una nuova proposta per il trattamento dell'anemia nei pazienti affetti da insufficenza renale cronica.

Iron supplementation is essential for the treatment of anemia in the chronic kidney disease (CKD) population. Liposomial iron is a preparation of ferric pyrophosphate carried within a phospholipidic membrane. Compared to other oral formulations, it is well absorbed from the gut and demonstrates high bioavailability together with a lower incidence of side effects. The aim of our study was to evaluate the effectiveness of treatment with liposomial iron compared to intravenous iron in a CKD population with anemia and iron deficiency. Our study is a single-center, prospective, randomized, fourth-phase study. Enrollment for the study began in October 2011 and CKD 3, 4 and 5 patients were randomized to receive either intravenous iron or liposomial iron in a 1:2 ratio. The primary outcome was set as the increase of hemoglobin from baseline. The secondary outcomes were the reduction of erythropoietin dosage by at least 25% in patients treated with erythropoiesis-stimulating agents and an increase in serum ferritin of 100 ng/ml from baseline values. In the preliminary study, 21 patients were analyzed, 14 of whom were treated with oral liposomial iron and 7 with intravenous iron. The observed increase of hemoglobin at 8 weeks compared to baseline was similar in both groups but was significant in the liposomial group only.

[Giant hepatic cyst in a patient with ADPKD]. / Cisti epatica gigante in una paziente affetta da malattia policistica autosomica dominante: caso clinico.

We present the case of a 39-year-old woman with autosomal dominant polycystic kidney disease (ADPKD). She was admitted to our hospital with marked dyspnea and epigastric pain. A diagnosis of giant hepatic cyst compressing the surrounding organs was made on the basis of the clinical and radiological findings. The patient underwent percutaneous aspiration of the cyst. The symptoms and radiological abnormalities were normalized within a few days of the minimally invasive aspiration procedure.