Multicenter evaluation of use of dried blood spot compared to conventional plasma in measurements of globotriaosylsphingosine (LysoGb3) concentration in 104 Fabry patients.

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.

Skin globotriaosylceramide 3 deposits are specific to Fabry disease with classical mutations and associated with small fibre neuropathy.

BACKGROUND: Fabry Disease (FD) is characterized by globotriaosylceramide-3 (Gb3) accumulation in several tissues and a small fibre neuropathy (SFN), however the underlying mechanisms are poorly known. This study aimed to: 1) ascertain the presence of Gb3 deposits in skin samples, by an immunofluorescence method collected from FD patients with classical GLA mutations or late-onset FD variants or GLA polymorphisms; 2) correlate skin GB3 deposits with skin innervation. METHODS: we studied 52 genetically-defined FD patients (32 with classical GLA mutations and 20 with late-onset variants or GLA polymorphisms), 15 patients with SFN associated with a specific cause and 22 healthy controls. Subjects underwent skin biopsy to evaluate Gb3 deposits and epi-dermal innervation. RESULTS: Skin Gb3 deposits were found in all FD patients with classical GLA mutations but never in FD patients with late-onset variants or GLA polymorphisms or in patients with SFN and healthy controls. Abnormal deposits were found inside different skin structures but never inside axons. FD patients with GB3 deposits showed lower skin innervation than FD patients with late-onset variants or polymorphisms. CONCLUSIONS: 1) Skin Gb3 deposits are specific to FD patients with classical GLA mutations; 2) Gb3 deposits were associated with lower skin innervation but they were not found inside axons, suggesting an indirect damage on peripheral small fibre innervation.

Exploratory screening for Fabry's disease in young adults with cerebrovascular disorders in northern Sardinia.

BACKGROUND: The etiologic determinants of stroke in young adults remain a diagnostic challenge in up to one-fourth of cases. Increasing evidences led to consider Fabry's disease (FD) as a possible cause to check up. We aimed at evaluating the prevalence of unrecognized FD in a cohort of patients with juvenile stroke in northern Sardinia. METHODS: For this study, we enrolled 178 patients consecutively admitted to our Neurological Ward for ischemic stroke, transient ischemic attack, intracerebral haemorrhage, neuroradiological evidence of silent infarcts, or white matter lesions possibly related to cerebral vasculopathy at brain MRI, and cerebral venous thrombosis. The qualifying events have to occur between 18 and 55 years of age. RESULTS: We identified two patients with an α-galactosidase A gene variant, with a prevalence of 0.9 %. According to recent diagnostic criteria, one patient, included for the occurrence of multiple white matter lesions at brain MRI, had a diagnosis of definite FD, the other, included for ischemic stroke, had a diagnosis of uncertain FD. CONCLUSIONS: Our study places in a middle position among studies that found a prevalence of FD up to 4 % and others that did not find any FD patients. Our findings confirm that FD should be considered in the differential diagnosis of patients with juvenile stroke, particularly those with a personal or familial history positive for cerebrovascular events, or evidence of combined cardiologic and/or renal impairment. All types of cerebrovascular disorders should be screened for FD, including patients with white matter lesions possibly related to cerebral vasculopathy at brain MRI.

De novo Diagnosis of Fabry Disease among Italian Adults with Acute Ischemic Stroke or Transient Ischemic Attack.

BACKGROUND AND PURPOSE: Cerebrovascular complications are often the first cause of hospitalization in patients with Fabry disease (FD). Screenings for FD among stroke patients have yielded discrepant results, likely as a result of heterogeneous or incomplete assessment. We designed a study to identify FD among adults 60 years of age or younger who were consecutively admitted for acute ischemic stroke or transient ischemic attack (TIA) to a stroke neurology service in Italy. METHODS: Patients with first-ever or recurrent events were included, irrespective of gender, risk factors, or stroke type. We screened male patients using α-galactosidase A enzyme assay, and female patients using DNA sequencing. FD was eventually established after a broad multidisciplinary discussion. RESULTS: We screened 108 patients (61% males, median age: 48 years); 84% of these patients had stroke. De novo FD diagnosis was established in 3 patients (2.8%; 95% confidence interval, .57-8.18): a 59-year-old man with recurrent lacunar-like strokes and multiple risk factors; a 42-year-old woman with recurrent cryptogenic minor strokes; and a 32-year-old woman with recurrent strokes previously attributed to Behçet's disease. Screened patients were systematically asked for typical FD symptoms; each of the de novo patients reported one or more of the following: episodes of hand/foot pain during fever, angiokeratoma, and family history of heart disease. In all of the patients events were recurrent, and lacunar-like infarcts characterized their brain imaging. CONCLUSIONS: Prevalence of FD among nonselected adults 60 years of age or younger with acute ischemic stroke or TIA is not negligible. A systematic search for FD in a stroke setting, using a comprehensive clinical, biochemical, and genetic screening protocol, may be worthwhile.

Vascular endothelial growth factor (VEGF-a) in Fabry disease: association with cutaneous and systemic manifestations with vascular involvement.

INTRODUCTION: Fabry disease is an X-linked inherited metabolic disorder characterized by the deficiency of lysosomal α-galactosidase A enzyme. This leads to the accumulation, into lysosomes through the body, of glycosphingolipids, mainly Gb3. Skin involvement and progressive multi-organ failure are usually observed. Endothelium is the preferential target of the Gb3 storage that determines endothelial dysfunction and vasculopathy leading to the clinical manifestations of the disease. The serum levels of Vascular Endothelial Growth Factor-A (VEGF-A), a specific endothelial cell mitogen, were analyzed in Fabry patients to explore a possible association to the clinical manifestations with vascular involvement. METHODS: Thirty-five patients with a biochemical and genetic diagnosis of Fabry disease, along with an age-gender-matched healthy control group, were enrolled. Serum samples were collected and analyzed by ELISA. The genetic mutations, the specific organ dysfunction, and the cardiovascular risk factors such as dyslipidaemia, diabetes, smoking habits and hypertension were evaluated in Fabry patients. RESULTS: The mean serum level of VEGF-A in Fabry patients group was significantly higher than in the control group (P=0.006). A statistical significant association, between VEGF-A levels and the skin manifestation including angiokeratomas, sweating abnormalities and Fabry Facies was found. An association was also found between high VEGF-A and specific GLA mutations, the male gender, the renal and neurological manifestations, the presence of eye vessels tortuosity, smoking habit and hypertension. CONCLUSIONS: We detected increased VEGF-A levels in patients with Fabry disease compared to the controls, and we hypothesized that this could be a response to the vascular damage characterising this lysosomal disorder. However, further studies are necessary to clarify the role of VEGF-A in Fabry.

Somatic and autonomic small fiber neuropathy induced by bortezomib therapy: an immunofluorescence study.

Bortezomib is a new chemotherapeutic agent approved for the treatment of relapsed/refractory and newly diagnosed multiple myeloma. One of the major side effects of bortezomib is a peripheral length-dependent sensory axonal neuropathy and, less frequently, a small fiber neuropathy. Autonomic symptoms like postural dizziness, syncope, diarrhoea, ileus, impotence and urinary disturbances have been reported, nevertheless, autonomic neuropathy has never been characterized. We describe by means of immunofluorescence, the involvement of autonomic skin nerve fibers in three patients with small fiber neuropathy induced by bortezomib treatment.

Distal extremity pain as a presenting feature of Fabry's disease.

OBJECTIVE: Fabry's disease (FD) is an X-linked lysosomal storage disease. Distal extremity pain can be an early finding and renal, cardiac, and cerebrovascular complications may lead to complications and mortality. Treatment is now available for these patients, who may not be diagnosed correctly for years if the neuropathic nature of the pain is not recognized. The aim of our study was to describe early clinical features in a cohort of patients with FD and to emphasize the importance of distal extremity pain for early diagnosis. METHODS: The medical charts of 35 patients with FD followed in a single center were reviewed. When data were incomplete, a detailed pain questionnaire was sent to patients. Nonresponders were contacted by telephone. RESULTS: Distal extremity pain was present in the majority of cases (25 of 35). The mean age at diagnosis of FD was 43.5 years (range 5-77 years). Distal extremity pain was more prevalent in males than females and occurred mostly in childhood or adolescence. When present at onset, the disease progressed with subsequent organ system involvement. Misdiagnoses were frequent and included growing pains, juvenile idiopathic arthritis, connective tissue disease, and gout. CONCLUSION: Clinical manifestations of FD, including episodes of severe pain in the feet and hands, often start in childhood. Distal extremity pain may be the only symptom for a considerable period of time. Patients may be wrongly labeled as having rheumatologic conditions, resulting in long diagnostic and therapeutic delays. Rheumatologists should be aware of the clinical aspects of FD and include it in the differential diagnosis of distal extremity pain in childhood and adolescence.

Nervous system and Fabry disease, from symptoms to diagnosis: damage evaluation and follow-up in adult patients, enzyme replacement, and support therapy.

The X-linked genetic Fabry disease causes multiorgan lesions due to intracellular storage of the substrate globotriaosylceramide. Neurological involvement ranges from painful, small fiber neuropathy to cerebrovascular disorders to multifocal aggressive forms. Disease identification through proper differential diagnosis and timely assessment of organ damage should guide a careful treatment planning. Mainstay treatment, include enzyme replacement and support therapy. Neurologists have a pivotal role in early instrumental and clinical detection of organ damage. A panel of experts has developed a set of consensus recommendations to guide the approach of neurologists to Fabry disease.

Small fiber neuropathy in female patients with fabry disease.

Recent studies suggest that heterozygous female Fabry disease (FD) patients develop peripheral neuropathy. We used skin biopsy to define somatic and autonomic peripheral nerve characteristics in 21 females with FD who were mainly asymptomatic and had normal renal function. Somatic epidermal and dermal autonomic nerve fiber reductions were found, prevalently in the leg, and no differences were found between symptomatic and asymptomatic individuals. Our findings suggest that females with FD, although asymptomatic, may have somatic and autonomic small fiber neuropathy.

Nature and prevalence of pain in Fabry disease and its response to enzyme replacement therapy--a retrospective analysis from the Fabry Outcome Survey.

BACKGROUND: Fabry disease is a multisystemic life-threatening lysosomal storage disorder caused by deficiency of alpha-galactosidase A. Symptoms of the disease may occur in different organs including kidney, heart, and the nervous system. OBJECTIVES: To evaluate the nature and prevalence of pain in a large cohort of patients with Fabry disease and to assess the effect of enzyme replacement therapy (ERT) with agalsidase alfa. METHODS: Retrospective analysis of the data of 752 patients with Fabry disease (393 females, 353 males) enrolled in the Fabry Outcome Survey, a multicentre database. RESULTS: The prevalence of pain in male patients was 81.4% (females 65.3%). Mean age at onset of pain was 14.8+/-1.0 year in males (females 19.8+/-1.4 y). Pain was most frequently reported in the hands (males 76%, females 60%) and feet (males 73%, females 52%), but often affected the whole body. Interference of pain with daily life was higher in females than in males, and was observed predominantly for general activities, mood, and normal work. Fifty-eight percent of the patients were on ERT with agalsidase alfa. At 24 and 36 months after commencement of ERT, pain severity classification shifted towards lower severity (P<0.05). Moreover, after 36 months, "average pain" and "pain now" were significantly reduced (P<0.05). CONCLUSIONS: Pain is one of the most prevalent symptoms in Fabry disease with onset early in childhood. ERT with agalsidase alfa significantly reduces pain in this debilitating disorder.

Motor evoked potentials in multiple sclerosis patients without walking limitation: amplitude vs. conduction time abnormalities.

We used Motor Evoked Potentials (MEPs), elicited by transcranial magnetic stimulation, for assessing a motor pathways dysfunction in a selected group of Multiple Sclerosis (MS) patients, without limitation in walking. We selected 32 Relapsing Remitting MS patients, in remission phase, with EDSS < or = 3.5 and 20 healthy individuals with similar height and age distribution. We measured the following MEP parameters: motor thresholds; central motor conduction time (CMCT); amplitude and area, both expressed as MEP/CMAP ratio. Patients were divided into two groups according to the EDSS score: non-disabled group (ND; EDSS 0-1.5) and disabled group (D; EDSS 2-3.5). Mean average MEP values were significantly different in the patients compared with the controls. Even in MS patients with no or minor neurological signs (ND group), MEP parameters showed differences from controls and furthermore all MEP parameters were significantly different in the D group compared with the ND group. The 75% of the patients had an amplitude or area alteration; this percentage was significantly higher than the percentage of patients with a CMCT alteration (56.2%). In addition, CMCT increase was always associated with reduced amplitude and area, but amplitude and area alterations were present also in patients with normal CMCT. In early stages of MS, the higher percentage shown in alteration of MEP amplitudes and areas as opposed to CMCTs has not previously been highlighted in the literature. Independently of its pathogenesis (demyelination or axonal loss), the amplitude or area decrease should be considered in clinical trials and in follow-up studies, as a marker of the motor pathways dysfunction, at least as much as CMCT increase.

Diagnosis of Anderson-Fabry's disease in over seventy-year-old women: description of two cases.

Anderson-Fabry's disease (AFD) is a rare inborn X-linked sphingolipid storage disorder. Deficient activity of the lysosomal enzyme alpha-galactosidase A (alpha-GAL-A) leads to progressive accumulation of glycosphingolipids within most visceral tissues and body fluids of affected patients, provoking a clinical syndrome that includes nervous system, renal, cardiac, ophthalmologic and cutaneous manifestations. Also heterozygous women, who had been considered as healthy carriers until recently, often demonstrate clinical signs of multi-organ involvement. In older women these manifestations are frequently attributed to other more common conditions of older age, and a genetic disorder is rarely hypothesized. We report the cases of two elderly women, who had been diagnosed with AFD at the ages of 70 and 74. Although it is a rare disease, AFD should be considered as a diagnostic hypothesis in women with a clinical history of cardiomyopathy and vascular encephalopathy, appearing at ages 40-50 without identification of major vascular risk factors.

Long-term evolution of anti-ganglioside antibody levels in patient with chronic dysimmune neuropathy under IVIg therapy.

The authors retrospectively examined the anti-ganglioside antibody (AGA) IgM level changes from 14 patients with chronic dysimmune neuropathy (5 with multifocal motor neuropathy and 9 with chronic inflammatory demyelinating polyneuropathy) treated with maintenance doses of intravenous immunoglobulins (IVIg). The median follow-up was 5 years. At last follow-up, 93% of the patients had an increment of AGA levels, and five patients with initial AGA values within normal range became positive during follow-up. Overall, median AGA titers significantly increased from the first to the last samples, despite a substantial clinical stability after the initial improvement with IVIg. The AGA increment rate was inversely correlated with IVIg infusions interval necessary to maintain therapeutic efficacy. Thus, antibody testing in the follow-up of patients with dysimmune neuropathies may be helpful to predict the decline of IVIg efficacy and to identify those patients who eventually take advantage from an increase in infusion frequency.

Subcortical damage and cortical functional changes in men and women with Fabry disease: a multifaceted MR study.

PURPOSE: To prospectively compare brain magnetic resonance (MR) imaging and hydrogen 1 (1H) MR spectroscopy findings and to use functional MR imaging to explore the patterns of brain activation in men and women with Fabry disease (FD). MATERIALS AND METHODS: Eight men and eight women with FD (mean age, 38.8 years +/- 13.9 [standard deviation]) with absent or mild neurologic deficit and 16 healthy control subjects (eight men and eight women; mean age, 42.7 years +/- 15.3) gave informed consent to participate in the study, which was approved by the local ethical committee. Patients and control subjects underwent MR imaging, 1H MR spectroscopy of the frontal cortex and subcortical white matter, and functional MR imaging during repetitive flexion-extension of the last four fingers of the right hand. Extent of cerebral white matter damage was rated on fluid-attenuated inversion recovery MR images by using a visual score. Areas of activation were identified by using statistical parametric mapping software and the adoption of a height threshold of P < .001 (uncorrected) and an extent threshold of P < .05 (corrected). RESULTS: Men and women with FD showed a similar distribution of cerebral white matter changes, lacunar and cortical infarcts, small hemorrhages, and vertebrobasilar dolichoectasia. No significant (P > .05) difference was observed between patients with FD and control subjects for concentration of N-acetylaspartate, creatine, and choline. During the motor task, patients showed recruitment of additional cortical areas in comparison with control subjects. Increased activation of the contralateral sensorimotor area correlated (P = .002) with extent of white matter damage. CONCLUSION: Subcortical ischemic changes in men and women with FD are similar and are associated with increased recruitment of the sensorimotor network during a simple motor task, which might limit the functional effect of the white matter small-vessel disease.

Diffuse structural and metabolic brain changes in Fabry disease.

OBJECTIVES: To assess structural and metabolic brain changes in subjects affected by Fabry disease (FD) or carrying the disease mutation. BACKGROUND: FD is an X-linked metabolic disorder due to alpha-galactosidase A deficiency, which leads to storage of glycosphingolipids in many tissues and organs. Previous MR studies have shown structural and metabolic brain abnormalities in FD patients. It is not clear, however, whether tissue damage can be seen in both the brains of hemizygous and heterozygous and whether quantitative MR metrics are useful to monitor disease evolution. DESIGN/METHODS: We studied 4 males and 4 females with FD. Each subject underwent brain proton MRI/MR spectroscopic imaging (MRSI) examinations to obtain measures of total brain volumes, total brain lesion volumes, magnetization transfer ratios (MTr) in WM and central brain levels of N-acetylaspartate (NAA) to creatine (Cr). A second MR examination was performed in five subjects after 2 years. RESULTS: Focal WM lesions were found in 2 males and 1 female. The MTr values were always low in the WM lesions of FD subjects (p < 0.001) and also were low in the normal-appearing WM of 2 affected males. Total brain volumes were never decreased in FD subjects. Brain NAA/Cr values were significantly (p = 0.005) lower in FD subjects than in normal controls and correlated closely with Rankin scale measures (r = -0.79). On follow-up examinations, no significant MR changes were found. However, the small changes in NAA/Cr correlated closely with changes in Rankin scores (r = -0.86). CONCLUSIONS: Subtle structural and metabolic tissue damage can extend beyond WM lesions in FD subjects. Diffuse brain NAA/Cr decrease can be found in FD subjects in relation to the degree of their CNS involvement and its evolution over time.

Parkinsonism and Anderson Fabry's disease: a case report.

We describe and present a videotape of a 57-year-old woman admitted to our Neurological Clinic at 46 years of age due to extrapyramidal manifestations suggesting Parkinson's disease (PD) and with a brain magnetic resonance imaging scan showing multi-infarctual leukoencephalopathy. Various investigations led to the diagnosis of Anderson Fabry's disease (AFD). We discuss the possibility of correlation between the patient's parkinsonism and AFD.

[Fabry disease in Italy: first epidemiologic and collaborative study]. / Primo studio epidemiologico e collaborativo italiano sulla malattia di Fabry.

The authors sought to define the prevalence of Fabry disease and to establish the incidence and its natural history in Italy. The aim of this study was to point out the first clinical signs and symptoms to perform an early diagnosis and hence to start a specific therapeutic treatment. Fabry disease is an inborn error of metabolism caused by the deficiency of the lysosomal enzyme alpha-galactosidase A. Fabry disease is a severe X-linked disorder presenting with a higher morbidity between the third and the fourth decade of life. Fabry disease may be confused with other diseases or completely misdiagnosed: its frequency is estimated worldwide to be 1:117000. In Italy, 65 patients have been identified by several specialized institutions; age, sex, onset of first clinical signs and symptoms were analyzed and reported. In conclusion, this is the first Italian collaborative study that allows to delineate and point out the clinical signs of Fabry disease to perform a correct and early diagnosis. Enzyme replacement therapy is now available and its early beginning can prevent renal and cardiac failure, improve the quality of life and life expectancy in these patients.