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INTRODUCTION: Despite major advances in the field of dialysis, there are still some unmet needs such as reducing inflammation through adequate depuration. It is well known that the wide spectrum of pro-inflammatory and pro-atherosclerotic uremic toxins are inefficiently removed by current dialysis techniques. Adsorption seems to be an extra tool to remove toxins, but its effect and optimization have not been widely studied. The aim of this report was to present preliminary results regarding the possibility of performing hemodiafiltration with a highly adsorptive polymethylmethacrylate membrane. METHODS: The study was first conducted in 10 patients in which the safety and feasibility of hemodiafiltration with PMMA BG-U 2.1 membrane were tested through measurement of hemolysis indices, transmembrane pressures, and dialysis adequacy. Twenty patients were prospectively observed for 18-month period in which they consecutively underwent standard hemodialysis, standard post-dilution hemodiafiltration, and polymethylmethacrylate-based post-dilution hemodiafiltration. Protein-bound uremic toxins concentrations and inflammatory markers were measured throughout the observed period. RESULTS: HDF-PMMA was inferior to HDF in convective volume, but KT/V was similar, and no differences were noted in operating pressures during the two treatments. During HDF-PMMA period of treatment, we observed a significant reduction of CPR levels, and HDF-PMMA was superior to all other treatments in hepcidin removal even if this did not significantly affect hemoglobin levels. HDF-PMMA could significantly reduce indoxyl sulfate (indoxyl) concentration over a period of 6 months but not for p-cresyl sulfate (p-cresyl). CONCLUSION: PMMA BG-U 2.1 membrane can be safely and efficiently used in hemodiafiltration. Moreover, as these preliminary results show, adding adsorption properties to convection and diffusion enabled an increased removal of indoxyl uremic toxin associated to a reduction in inflammation markers as CRP and hepcidin without any negative impact on albumin levels.
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BACKGROUND: Peripherally Inserted Central Catheters play an increasingly important role in Central Venous Access Devices. However, the use of these devices should be carefully considered in specific situations such as central catheterisation in patients with chronic kidney disease. When evaluating the feasibility of placement for a patient undergoing dialysis, the relationship between changes in circulating volume before and after dialysis treatment, and potential variations in the size of deep veins in the upper limbs, should be considered. MATERIALS: Upper limb veins, specifically the basilic or brachial veins, were identified and measured before and after dialysis treatment. Patient data and weight loss data during dialysis treatment were also collected. Linear regression analysis was performed to assess the correlation between the variables. RESULTS: The average variation in vein size for the entire sample was +0.17 ± 0.43 mm. The mean volume removed was 2.2 ± 0.8 l. In subgroup 1 (fluid volume loss <2000 ml), the population experienced a decrease in the measured vein size after dialysis. In subgroup 2 (fluid volume loss ⩾2000 ml), the population experienced an increase in the measured vein size after dialysis. CONCLUSIONS: Upper arm vascular access placement in dialysed patients with fluid removal of less than 2000 ml should be performed after the dialysis session. Conversely, in dialysed patients with fluid removal of more than 2000 ml, where a significant increase in vein size was observed, vascular access placement should be performed before the dialysis session when the veins are smaller. Additionally, it should be noted that in patients with chronic kidney disease, the venous system of the upper limbs should be preserved as much as possible to prevent thrombosis and stenosis in potential arteriovenous fistula creation.
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BACKGROUND: Fabry disease is a rare progressive X-linked lysosomal storage disease caused by mutations in the GLA gene that encodes α-galactosidase A. Agalsidase beta is a recombinant enzyme replacement therapy authorized in Europe at a standard dose of 1.0 mg/kg intravenously every other week at an initial infusion rate of ≤ 0.25 mg/min until patient tolerance is established, after which the infusion rate may be increased gradually. However, specific practical guidance regarding the progressive reduction in infusion time is lacking. This study investigated a new and specific protocol for reducing agalsidase beta infusion time in which a stable dosage of 15 mg/h is infused for the first four months, and the infusion rate is increased progressively from 15 to 35 mg/h for the subsequent four infusions. The shortest infusion time is reached after six months and maintained thereafter. The incidence of infusion-associated reactions (IARs) and the development of anti-drug antibodies were analyzed, and the disease burden and the clinical evolution of the disease at 12 months were evaluated. RESULTS: Twenty-five of the 31 patients were naïve to enzyme or chaperone treatment at baseline and six patients had been switched from agalsidase alfa. The reduced infusion time protocol was well tolerated. Only one patient exhibited an IAR, with mild symptoms that resolved with low-dose steroids. Six patients globally seroconverted during treatment (4 with a classic phenotype and 2 with late-onset disease). All but three patients were seronegative at month 12. All patients were stable at the study's end (FAbry STabilization indEX value < 20%); reducing infusion time did not negatively impact clinical outcomes in any patient. The perceived medical assessment showed that the quality of life of all patients improved. CONCLUSIONS: The study demonstrates that reducing agalsidase beta infusion time is possible and safe from both an immunogenic and clinical point of view. The use of a low infusion rate in the first months when the probability of onset of the development of antibodies is higher contributed to very limited seroconversion to antibody-positive status.
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Enfermedad de Fabry , Isoenzimas , alfa-Galactosidasa , Humanos , alfa-Galactosidasa/uso terapéutico , Calidad de Vida , Formación de Anticuerpos , Incidencia , Resultado del Tratamiento , Anticuerpos/uso terapéutico , Proteínas Recombinantes/uso terapéutico , Terapia de Reemplazo Enzimático/métodos , ItaliaRESUMEN
Background: The prevalence of atrial fibrillation (AF) in end stage kidney disease (ESKD) patients undergoing dialysis is high, however, the high risk of bleeding often hampers with a correct anticoagulation in ESKD patients with AF, despite high thromboembolic risk. Left atrial appendage (LAA) occlusion is a anticoagulation (OAT) for thromboembolism prevention in AF populations with high hemorrhagic risk. Methods and Results: The purpose of the study was to evaluate the efficacy and safety of LAA occlusion in a cohort of dialysis patients undergoing the procedure (LAA occlusion cohort, n = 106), in comparison with two other ESKD cohorts, one taking warfarin (Warfarin cohort, n = 114) and the other without anticoagulation therapy (No-OAT cohort, n = 148). After a median follow-up of 4 years, a Cox regression model, adjusted for possible confounding factors, showed that the hazard ratios (HRs) of thromboembolic events in the LAA occlusion cohort were 0.19 (95%CI 0.04-0.96; p = 0.045) and 0.16 (95%CI 0.04-0.66; p = 0.011) as compared with Warfarin and No-OAT cohorts, respectively. The HR of bleeding in the LAA occlusion cohort was 0.37 (95%CI 0.16-0.83; p = 0.017) compared to Warfarin cohort, while there were no significant differences between the LAA occlusion and the No-OAT cohort (HR 0.51; 95%CI 0.23-1.12; p = 0.094). Adjusted Cox regression models showed lower mortality in patients undergoing LAA occlusion as compared with both the Warfarin cohort (HR 0.60; 95%CI 0.38-0.94; p = 0.027) and no-OAT cohort (HR 0.52; 95%CI 0.34-0.78; p = 0.002). Thromboembolic events in the LAA occlusion cohort were lower than expected according to the CHA2DS2VASc score (1.7 [95%CI 0.3-3.0] vs 6.7 events per 100 person/years, p < 0.001). Conclusion: In ESKD patients with AF, LAA occlusion is safe and effective and is associated with reduced mortality compared with OAT or no therapy.
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BACKGROUND: Hypertrophic cardiomyopathy (HCM) and Fabry disease cardiomyopathy (FD) are phenocopies, as they show left ventricular hypertrophy (LVH). The left atrium (LA) is emerging as a potential marker of disease severity in both cardiomyopathies. The present study compares HCM and FD cardiomyopathy with similar degree of LVH, exploring LA morpho-functional parameters and the correlates of clinical outcome. METHODS: We performed a comprehensive CMR-based comparison between 30 HCM and 30 FD patients matched on age, sex, BSA, LV mass and major cardiovascular risk factors affecting LA remodeling (arterial hypertension and diabetes). 30 healthy controls were also included. CMR feature tracking (CMR-FT) analysis, T1 mapping and conventional parameters were evaluated. Patients also underwent transthoracic echocardiography for LV diastolic function assessment. Clinical events at follow-up were collected (atrial and ventricular events, bradyarrhythmia, heart failure (HF) hospitalization and death). RESULTS: HCM patients showed greater LA remodeling compared to FD patients, namely higher LA end-systolic volume index (LAVi max), lower LA-ejection fraction (LA-EF) and worse reservoir (εs) and booster function (εa) (all p < 0.05). Accordingly, these parameters have demonstrated good potential for distinguishing between FD and HCM (AUC 0.68-0.73, all p < 0.05), with LAVi max being an independent predictor for HCM diagnosis (OR 1.07, 95%CI 1.011-1.132, p 0.02). Moreover, in HCM patients a significant association between εs and HF occurrence was observed at 2-year follow-up (OR 0.85, 95%CI 0.72-0.99, p 0.04). CONCLUSIONS: In HCM, LA remodeling is greater than in FD cardiomyopathy with similar LVH, and reservoir strain is associated with HF at follow-up.
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Nephropathy is one of the main features of Fabry disease (FD) that leads, in untreated patients with classical mutations, to end-stage renal disease (ESRD) from the third to the fifth decade of life. The availability of a specific treatment modified the natural history of FD; in particular, it was widely reported that enzyme replacement therapy (ERT) is able to slow the progression of the disease. Regarding Fabry nephropathy, several reports have documented an elevated estimated glomerular filtration rate (eGFR) slope in untreated patients as expression of a rapid disease progression towards ESRD. Otherwise, the prompt start of treatment may be beneficial in stabilizing renal function or slowing its decline. Therefore, based on data in the literature about the effects of ERT on eGFR decline and on the evidence supporting the role of eGFR slope as a surrogate endpoint for chronic kidney disease progression, we suggest, in this 'Expert Opinion', that a treatment should be defined effective when eGFR decline is <1 ml/min/1.73 m2/year and not effective when eGFR loss remains ≥3 ml/min/1.73 m2/year (≥2.5 ml/min/1.73 m2/year in females). Moreover, practical clinical recommendations and guidance for Fabry patients suggests that a change in treatment may be appropriate if individualized therapeutic goals are not achieved. Since a dose-dependent efficacy has been demonstrated for ERT, we suggest considering a switch to a higher dose of ERT in symptomatic adult Fabry patients (ages 18-60 years) with an eGFR of 45-90 ml/min/1.73 m2 and treated with a stable dose of ERT for at least 1 year, in which a linear negative slope of eGFR of 3 ml/min/1.73 m2/year for males (2.5 ml/min/1.73 m2/year for females) was observed.
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Enfermedad de Fabry , Enfermedades Renales , Fallo Renal Crónico , Adulto , Masculino , Femenino , Humanos , Enfermedades Renales/etiología , Tasa de Filtración Glomerular , Fallo Renal Crónico/terapia , Fallo Renal Crónico/tratamiento farmacológico , Terapia de Reemplazo Enzimático/efectos adversos , alfa-Galactosidasa/uso terapéuticoRESUMEN
BACKGROUND: A small but significant reduction in left ventricular (LV) mass after 18 months of migalastat treatment has been reported in Fabry disease (FD). This study aimed to assess the effect of migalastat on FD cardiac involvement, combining LV morphology and tissue characterisation by cardiac magnetic resonance (CMR) with cardiopulmonary exercise testing (CPET). METHODS: Sixteen treatment-naïve patients with FD (4 women, 46.4±16.2 years) with cardiac involvement (reduced T1 values on CMR and/or LV hypertrophy) underwent ECG, echocardiogram, troponin T and NT-proBNP (N-Terminal prohormone of Brain Natriuretic Peptide) assay, CMR with T1 mapping, and CPET before and after 18 months of migalastat. RESULTS: No change in LV mass was detected at 18 months compared to baseline (95.2 g/m2 (66.0-184.0) vs 99.0 g/m2 (69.0-121.0), p=0.55). Overall, there was an increase in septal T1 of borderline significance (870.0 ms (848-882) vs 860.0 ms (833.0-875.0), p=0.056). Functional capacity showed an increase in oxygen consumption (VO2) at anaerobic threshold (15.50 mL/kg/min (13.70-21.50) vs 14.50 mL/kg/min (11.70-18.95), p=0.02), and a trend towards an increase in percent predicted peak VO2 (72.0 (63.0-80.0) vs 69.0 (53.0-77.0), p=0.056) was observed. The subset of patients who showed an increase in T1 value and a reduction in LV mass (n=7, 1 female, age 40.5 (28.6-76.0)) was younger and at an earlier disease stage compared to the others, and also exhibited greater improvement in exercise tolerance. CONCLUSION: In treatment-naïve FD patients with cardiac involvement, 18-month treatment with migalastat stabilised LV mass and was associated with a trend towards an improvement in exercise tolerance. A tendency to T1 increase was detected by CMR. The subset of patients who had significant benefits from the treatment showed an earlier cardiac disease compared to the others. TRIAL REGISTRATION NUMBER: NCT03838237.
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Enfermedad de Fabry , Cardiopatías , Humanos , Femenino , Adulto , Imagen por Resonancia Magnética , 1-Desoxinojirimicina , Valor Predictivo de las PruebasRESUMEN
AA amyloidosis may complicate several chronic inflammatory conditions. From a clinical point of view, causality between inflammatory pathology and AA amyloidosis can be assumed because of the data described in the literature; some of the best known include rheumatoid arthritis, ankylosing spondylitis, inflammatory bowel disease, and chronic infections. Singles cases of inflammatory diseases have been found at AA amyloidosis. Causality becomes more plausible if at least two different cases with AA amyloidosis are both found to have the same rare inflammatory disease. We describe the case of a patient with primary sclerosing cholangitis (PSC) with development of AA amyloidosis conditioning a nephrotic syndrome, likely secondary to failure to control the chronic inflammatory process. Only two cases in the literature describe the association of this rare disease and the appearance of AA amyloidosis. The treatment of AA amyloidosis consists in treating the underlying inflammatory disorder; to date, few effective treatments are available for PSC. Therefore, and in view of the limited data in the literature, we believe it is important to describe its association.
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Anderson-Fabry Disease (FD) is an X-linked lysosomal disorder caused by mutations in GLA, the gene encoding the lysosomal hydrolase α-galactosidase A (α-Gal A), leading to accumulation of glycosphingolipids in the lysosomes. FD is a multisystemic disorder leading to progressive cardiovascular, cerebrovascular and kidney dysfunction. Phenotypes are divided in two main classes, classic or non-classic, depending on substrate accumulation, age at onset, disease manifestation, severity and progression. The more severe classical phenotype is generally associated with mutations leading to absent or strongly reduced α-Gal A activity, while mutations with higher residual activity generally lead to the non-classical one. Approximately 70% of the over 1,000 Fabry disease-associated mutations are missense mutations, some leading to endoplasmic reticulum (ER) retention of mutant protein. We hypothesized that such mutations could be associated, besides the well-known absence of α-Gal A function/activity, to a possible gain of function effect due to production of a misfolded protein. We hence expressed α-Gal A missense mutations in HEK293 GLA -/- cells and investigated the localization of mutant protein and induction of ER stress and of the unfolded protein response (UPR). We selected a panel of 7 missense mutations, including mutants shown to have residual or no activity in vitro. Immunofluorescence analysis showed that mutants with residual activity have decreased lysosomal localization compared with wild type, and partial retention in the ER, while missense mutants with no residual activity are fully retained in the ER. UPR (ATF6 branch) was significantly induced by all but two mutants, with clear correlation with the extent of ER retention and the predicted mutation structural effect. These data identify a new molecular pathway, associated with gain of function effect, possibly involved in pathogenesis of FD.
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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.
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Enfermedad de Fabry , Masculino , Femenino , Humanos , Enfermedad de Fabry/diagnóstico , Enfermedad de Fabry/genética , Enfermedad de Fabry/terapia , alfa-Galactosidasa/genética , alfa-Galactosidasa/uso terapéutico , Terapia de Reemplazo Enzimático , Consenso , Calidad de Vida , Glicoesfingolípidos , BiomarcadoresRESUMEN
AIM: The current study was designed at assessing whether the sympathetic cardiovascular drive (SNS) is differently activated in chronic kidney disease (CKD) patients displaying less or more elevated resting heart rate (HR) values. It was also designed at determining at which HR cutoff value the SNS displays a greater activation. METHODS: In 95 CKD middle-age patients we evaluated muscle sympathetic nerve activity (MSNA, microneurography) and venous plasma norepinephrine (HPLC assay), subdividing the patients in different groups according to their resting clinic and 24-h HR. RESULTS: In CKD progressively greater values of clinic or 24-h HR were associated with a progressive increase in both MSNA and norepinephrine. HR cutoff values indicated by large-scale clinical trials for determining cardiorenal risk, that is more than 80âbpm, were associated with MSNA values significantly greater than the ones detected in patients with lower HR, this being the case also for norepinephrine. Both MSNA and norepinephrine were significantly related to clinic ( r â=â0.47, P â<â0.0001 and r â=â0.26, P â<â0.0001, respectively) and 24-h ( r â=â0.42, P â<â0.0001 and r â=â0.27, P â<â0.0001, respectively) HR. MSNA, norepinephrine, but not HR, were significantly and inversely related to estimated glomerular filtration rate (eGFR) values ( r â=â-0.47, r â=â-0.23, P â<â0.0001 and P â<â0.02, respectively). CONCLUSION: In CKD both clinic and 24-h HR values greater than 80âbpm are associated with an enhanced sympathetic activation, which parallelles for magnitude the HR elevations. The sensitivity of HR as sympathetic marker is limited; however, no significant relationship being detected between HR and eGFR or left ventricular mass index.
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Enfermedades Cardiovasculares , Insuficiencia Renal Crónica , Presión Sanguínea/fisiología , Enfermedades Cardiovasculares/etiología , Factores de Riesgo de Enfermedad Cardiaca , Frecuencia Cardíaca/fisiología , Humanos , Persona de Mediana Edad , Norepinefrina , Insuficiencia Renal Crónica/complicaciones , Factores de Riesgo , Sistema Nervioso SimpáticoRESUMEN
[This corrects the article DOI: 10.1093/ckj/sfab148.].
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We present the case of a 76-year-old man with late-onset Fabry disease caused by the p.N215S missense mutation, with Fabry cardiomyopathy and nephropathy. In this case, the diagnosis of Fabry disease was incidental and followed minimal change disease (MCD) onset, with nephrotic syndrome and acute kidney injury requiring renal replacement therapy. Fabry nephropathy associated with the p.N215S mutation is becoming increasingly recognized among older patients. The importance of electron microscopy is herein highlighted and histological features common to Fabry nephropathy and MCD are discussed, along with the challenges associated with the diagnosis and clinical management.
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AIMS: Fabry cardiomyopathy is characterized by glycosphingolipid storage and increased myocardial trabeculation has also been demonstrated. This study aimed to explore by cardiac magnetic resonance whether myocardial trabecular complexity, quantified by endocardial border fractal analysis, tracks phenotype evolution in Fabry cardiomyopathy. METHODS AND RESULTS: Study population included 20 healthy controls (12 males, age 32±9) and 45 Fabry patients divided into three groups: 15 left ventricular hypertrophy (LVH)-negative patients with normal T1 (5 males, age 28±13; Group 1); 15 LVH-negative patients with low T1 (9 males, age 33±9.6; Group 2); 15 LVH-positive patients (11 males, age 53.5±9.6; Group 3). Trabecular fractal dimensions (Dfs) (total, basal, mid-ventricular, and apical) were evaluated on cine images. Total Df was higher in all Fabry groups compared to controls, gradually increasing from controls to Group 3 (1.27±0.02 controls vs. 1.29±0.02 Group 1 vs. 1.30±0.02 Group 2 vs. 1.34±0.02 Group 3; P<0.001). Group 3 showed significantly higher values of all Dfs compared to the other Groups. Both basal and total Dfs were significantly higher in Group 1 compared with controls (basal: 1.30±0.03 vs. 1.26±0.04, P =0.010; total: 1.29±0.02 vs. 1.27±0.02, P=0.044). Total Df showed significant correlations with: (i) T1 value (r=-0.569; P<0.001); (ii) LV mass (r=0.664, P<0.001); (iii) trabecular mass (r=0.676; P <0.001); (iv) Mainz Severity Score Index (r=0.638; P<0.001). CONCLUSION: Fabry cardiomyopathy is characterized by a progressive increase in Df of endocardial trabeculae together with shortening of T1 values. Myocardial trabeculation is increased before the presence of detectable sphingolipid storage, thus representing an early sign of cardiac involvement.
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Cardiomiopatías , Enfermedad de Fabry , Enfermedad de Fabry/complicaciones , Enfermedad de Fabry/diagnóstico por imagen , Humanos , Hipertrofia Ventricular Izquierda/diagnóstico por imagen , Hipertrofia Ventricular Izquierda/etiología , Masculino , Estudios Prospectivos , Función Ventricular IzquierdaRESUMEN
Fabry disease is a rare X-linked lysosomal storage disorder caused by mutations in the GLA gene, leading to deficient α-galactosidase A activity and, consequently, to glycosphingolipid accumulation in a wide variety of cells. Fabry disease due to N215S (c.644A>G, p.Asn215Ser) missense mutation usually results in a late-onset phenotype presenting with isolated cardiac involvement. We herein present the case of a patient with N215S mutation with cardiac involvement, namely left ventricular hypertrophy and ventricular arrhythmias, and end-stage renal disease requiring kidney transplantation. To the best of our knowledge, this is the first report of a kidney-transplanted Fabry patient treated with oral pharmacologic chaperone migalastat.
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OBJECTIVES: To elaborate an ECG-based nomogram estimating the probability to detect cardiac involvement by cardiac magnetic resonance (CMR) in Fabry Disease (FD). METHODS: 119 FD patients and 26 healthy controls underwent ECG and CMR. Test (n = 88, 60%) and validation cohorts (n = 57, 40%) were randomly derived. Cardiac involvement was defined as the presence of low myocardial T1 value, a CMR-surrogate of myocardial glycosphingolipid storage. ECG changes associated with low T1 value were identified in the test cohort, included in the nomogram and then tested in the validation cohort. RESULTS: Sokolow-Lyon index (AUC = 0.769), ratio between P-wave and PR-segment durations (Pwave/PRsegment) (AUC = 0.778), QRS duration (AUC = 0.703), QT (AUC = 0.769) duration were independently associated with the presence of low T1 on CMR at multivariate analysis. An ECG-based nomogram including these four parameters was accurate in identifying patients with CMR evidence of glycosphingolipid storage (c-index of the derived-nomogram = 0.90 in the test group; 0.81 in the validation group). CONCLUSION: We propose a practical ECG-based nomogram accurately estimating the probability to detect low T1 values by CMR in FD patients. The application of this tool in clinical practice could improve early detection of FD cardiac involvement.
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Enfermedad de Fabry , Estudios Transversales , Diagnóstico Precoz , Electrocardiografía , Enfermedad de Fabry/diagnóstico por imagen , Humanos , Imagen por Resonancia Cinemagnética , Miocardio , Valor Predictivo de las Pruebas , ProbabilidadRESUMEN
OBJECTIVES: The search in the urinary sediment (U-sed) of fat particles with peculiar morphology is a simple and inexpensive tool for the diagnosis of Fabry disease (FD) nephropathy. In this study we investigated the morphology of a high number of such fat particles with the aim to obtain a morphological classification to be used for their identification. METHODS: Study of the morphology of fat particles in the U-sed of a cohort of FD patients using: bright field plus phase contrast microscopy (BF + PC), polarized light microscopy (POL), and transmission electron microscopy (TEM). Comparison of these results with those obtained for the fat particles seen in the U-sed of a control group (CG) of patients with non-FD glomerulopathies. RESULTS: FD: 18 U-sed from six patients (three samples/patient) were prospectively investigated and 506 fat particles identified. With BF + PC, these were classified in eight morphological categories (seven of which were confirmed by TEM), and with POL in 10 others. CG: eight U-sed from eight patients were investigated and 281 fat particles identified. These fell into four BF + PC morphological categories and into eight POL categories. While some categories were significantly more frequent in FD others were more frequent in the CG. CONCLUSIONS: Our study demonstrates that 1. The morphology of fat particles found in the U-sed of FD patients is much wider and complex than that described so far 2. Several significant differences exist in the morphology of such fat particles between FD and CG patients.
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Enfermedad de Fabry , Enfermedades Renales , Enfermedad de Fabry/diagnóstico , Humanos , Microscopía de Contraste de FaseRESUMEN
OBJECTIVES: Fabry disease (FD) is an X-linked lysosomal storage disorder, resulting from a deficiency of the enzyme α-galactosidase A, responsible for breaking down glycolipids such as globotriaosylceramide and its deacylated derivative, globotriaosylsphingosine (LysoGb3). Here, we compare the levels of LysoGb3 in dried blood spots (DBS) and plasma in patients with classic and late-onset phenotypes. METHODS: LysoGb3 measurements were performed in 104 FD patients, 39 males and 65 females. Venous blood was collected. A portion was spotted onto filter paper and another portion separated to obtain plasma. The LysoGb3 concentrations in DBS and plasma were determined by highly sensitive electrospray ionization liquid chromatography tandem mass spectrometry. Agreement between different matrices was assessed using linear regression and Bland Altman analysis. RESULTS: The method on DBS was validated by evaluating its precision, accuracy, matrix effect, recovery, and stability. The analytical performances were verified by comparison of a total of 104 paired DBS and plasma samples from as many FD patients (representing 46 GLA variants). There was a strong correlation between plasma and the corresponding DBS LysoGb3 concentrations, with few exceptions. Discrepancies were observed in anemic patients with typically low hematocrit levels compared to the normal range. CONCLUSIONS: The method proved to be efficient for the rapid analysis of LysoGb3. DBS provides a convenient, sensitive, and reproducible method for measuring LysoGb3 levels for diagnosis, initial phenotypic assignment, and therapeutic monitoring in patients with FD.