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Catharina Whybra

Publications and source records attributed to Catharina Whybra.

9 recordsLinked to original sources
PubMed2006

IgA nephropathy in two adolescent sisters heterozygous for Fabry disease.

We report a 16-year-old girl and her one-year-younger sister, both heterozygous for the c.34del24 mutation of the GLA (alpha-galactosidase A) gene, which they inherited from their father who is affected by Fabry disease (FD). Both girls presented with macrohematuria and rapidly progressing proteinuria. Urine analysis revealed glomerular hematuria and a nephrotic range of proteinuria suggesting a concomitant glomerulonephritis. Light microscopy of kidney biopsy was characteristic of IgA nephropathy (IgA deposits in mesangial areas and glomerular capillary loops, and mesangial hypercellularity), whereas electron microscopy showed changes typical of Fabry disease (multiple osmiophilic inclusions in the subendothelial and mesangial areas). These two cases and similar reports in the literature suggest that IgA nephropathy in FD is not merely coincidental.

Adult↗
PubMed2006

Pattern of microstructural brain tissue alterations in Fabry disease: a diffusion-tensor imaging study.

Fabry disease (FD) is a lysosomal storage disorder that is associated with marked cerebrovascular disease. Conventional MRI shows a progressive load of white matter lesions (WMLs) due to cerebral vasculopathy in the course of FD. To quantify brain structural changes in clinically affected male and female patients with FD we performed a prospective Diffusion-Tensor Imaging (DTI) study in 27 adult Fabry patients (13m, 14f) and 21 age-matched controls (12 m, 9f). Global Mean Diffusivity (MD) was increased in FD (P = 0.003) whereas global Fractional Anisotropy (FA) did not differ significantly between FD and controls. Even FD patients without significant WMLs (9m, 9f) showed increased global MD (P = 0.004). Regions of interest with significant MD elevations were located in the frontal, parietal and temporal white matter. No differences of thalamic and hippocampal DTI measurements could be detected between FD and controls. DTI parameters did not differ between male and female patients. The data provide the first evidence of a pattern of marked structural brain tissue alterations in adult FD male and female patients even without WMLs. DTI seems to be an appropriate diagnostic tool to quantify brain tissue integrity in FD. Moreover, this method could be favorable for longitudinal assessment of brain structure alterations in FD, and for monitoring the cerebral effects of enzyme replacement therapy.

Adult↗
PubMed2006

Clinical manifestations of Fabry disease in children: data from the Fabry Outcome Survey.

BACKGROUND: Fabry disease is a rare X-linked disorder caused by deficient activity of the enzyme alpha-galactosidase A. This produces progressive lysosomal accumulation of globotriaosylceramide throughout the body, leading to organ failure and premature death. AIM: Here, we present the clinical manifestations of Fabry disease in children enrolled in FOS--the Fabry Outcome Survey--a European database of the natural history of Fabry disease and the effects of enzyme replacement therapy with agalsidase alfa (Replagal). METHODS: Currently, there are 545 patients in FOS, from 11 European countries. We analysed the baseline demographic and clinical characteristics of 82 of these patients (40 boys, 42 girls) who were below 18 y of age. The median age at evaluation (defined as the median age at entry into FOS) was 12.5 and 13.2 y for boys and girls, respectively. RESULTS: The most frequent early clinical manifestations of Fabry disease were neurological (acroparaesthesiae, altered temperature sensitivity) and gastrointestinal symptoms (altered bowel habits and abdominal pain), which were documented in about 80% and 60% of patients, respectively, at the time of evaluation and subsequent entry into FOS. Tinnitus, vertigo, fatigue and angiokeratoma were present in over 40% of patients. Symptoms were noted in early childhood and occurred with similar frequency in boys and girls, although the onset of symptoms was 2-5 y later in girls than in boys. There was an approximately 3-y delay from onset of symptoms to diagnosis, and patients were frequently misdiagnosed. CONCLUSION: Although the life-threatening complications of Fabry disease, such as stroke and renal and heart failure, are not seen in children, the present analysis shows that other symptoms are common and may have an impact on quality of life.

Adolescent↗
PubMed2006

Disease manifestations and X inactivation in heterozygous females with Fabry disease.

AIM: Fabry disease is an X-linked lysosomal storage disorder characterized by an accumulation of neutral glycosphingolipids in multiple organ systems caused by alpha-galactosidase A deficiency due to mutations in the GLA gene. The majority of heterozygous females show the characteristic signs and symptoms of the disease, and some of them are severely affected. The current hypothesis for the occurrence of disease manifestations in females is skewed X inactivation favouring the mutant GLA allele. METHOD: We analyzed the patterns of X inactivation in the leukocytes of 28 biochemically and genetically characterized symptomatic Fabry disease heterozygotes and their correlation with clinical and biochemical disease expression. RESULTS: X inactivation patterns in symptomatic females who are heterozygous for Fabry disease did not differ from those of female controls of the same age (p = 0.669). Thirteen (46%) of the 28 females with Fabry disease showed random X inactivation, ten (36%) moderate skewing, and five (18%) highly skewed X inactivation. Segregation analysis was performed in the families of six females who had highly or moderately skewed X inactivation. In four of these females, skewing favoured the wild-type GLA allele and in the other two skewing favoured the mutant allele. Patterns of X inactivation or the extent of skewing were not related to the severity of clinical manifestations or to residual enzyme activity. CONCLUSION: In this study we provide evidence that heterozygous females with Fabry disease show random X inactivation. Our data do not support the hypothesis that the occurrence and severity of disease manifestations in the majority of Fabry heterozygotes are related to skewed X inactivation.

Adolescent↗
PubMed2006

Enzyme-replacement therapy with agalsidase alfa in children with Fabry disease.

CONTEXT: Fabry disease is an X-linked multisystem disorder. Enzyme-replacement therapy in adults has limited efficacy in treating major sequelae of advanced Fabry disease, such as kidney failure or stroke. This prompted a study of the safety and efficacy of enzyme replacement at an earlier stage of Fabry disease. OBJECTIVES: Our purpose with this work was to evaluate safety and to explore efficacy of enzyme treatment with agalsidase alfa in pediatric patients with Fabry disease. METHODS: We conducted a 6-month open-label study at 3 tertiary care centers with 24 children (19 boys and 5 girls) with a mean age of 11.8 (range: 6.5-18) years, to examine safety parameters, including infusion reactions and antiagalsidase alfa antibodies. RESULTS: Agalsidase alfa was well tolerated, and all of the patients completed the study. Six boys and 1 girl had mild-to-moderate infusion reactions. One boy developed transient immunoglobulin G antibodies against agalsidase alfa. The boys showed a significant reduction in plasma globotriaosylceramide on treatment. Mean estimated glomerular filtration rate, cardiac structure, and function were normal and did not change over 26 weeks. Heart rate variability, as determined by 2-hour ambulatory monitoring, was decreased in the boys compared with the girls at baseline. All indices of heart rate variability improved significantly in the boys. Three patients with anhidrosis, as determined by quantitative sudomotor axon reflex testing, developed sweating. Six of 11 patients could reduce or cease their use of antineuropathic analgesics. CONCLUSIONS: Enzyme replacement with agalsidase alfa was safe in this study. The exploratory efficacy analysis documented increased clearance of globotriaosylceramide and improvement of autonomic function. Prospective long-term studies are needed to assess whether enzyme replacement initiated early in patients with Fabry disease is able to prevent major organ failure in adulthood.

Adolescent↗
PubMed2005

Thirty-four novel mutations of the GLA gene in 121 patients with Fabry disease.

Fabry disease (FD) is an X-chromosomal disorder caused by mutations in the GLA gene encoding the lysosomal enzyme alpha-galactosidase A. We performed mutation screening on a cohort of 121 patients including 84 male and 37 female index cases and identified a total of 90 different mutations, 34 of which are reported for the first time here. Both point mutations (74.4%) and 'short length' rearrangements (25.6%) were found, including missense (54.4%), nonsense (14.4%), and splice site point mutations (5.6%), deletions (17.8%) or insertions/duplications (5.6%) of a few nucleotides, and complex rearrangements including larger deletions (2.2%). GLA mutations were identified in 82 (97.6%) of the 84 unrelated male patients.

Adolescent↗
PubMed2003

The early clinical phenotype of Fabry disease: a study on 35 European children and adolescents.

UNLABELLED: Fabry disease (FD) is a debilitating progressive multisystem X-linked lysosomal storage disorder. It was generally believed that the disease affects only adult males. Through systematic pedigree analysis, we identified 35 paediatric FD patients (age 1 to 21 years, mean 12.6 years) in 25 families. Predominant signs in this cohort were: acroparesthesia, hypohidrosis, and cornea verticillata. Neurological and psychological changes, such as tinnitus, recurrent vertigo, headache, diminished level of activity, fatigue, and depression were often observed. Angiokeratoma and gastrointestinal symptoms were frequent. Some patients also showed cardiac abnormalities. Six children and adolescents (three males and three females) over 14 years of age had renal involvement (all with proteinuria, one male had a decreased creatinine clearance of 62 ml/min). No males, but three females (1.5, 4 and 9 years of age), were free of signs and symptoms. Males (n=15, age 1 to 21 years, mean 12.4 years) and females (n=20, age 1.5 to 20 years, mean 12.7 years) showed comparable disease severity. However, the clinical courses demonstrated a wide intra- and interfamilial variability and tended to be more heterogeneous in the girls. Female patients are frequently affected at an early age, not much differently than males. They should be carefully examined because most carriers are symptomatic. CONCLUSION: Fabry disease usually becomes clinically manifest in childhood. Renal involvement can begin in adolescence. The diagnosis is made following a high level of suspicion or systematic pedigree analysis. It is crucial for paediatric Fabry disease patients to have early access to optimal supportive symptomatic management. Enzyme replacement therapy has shown promising effectiveness in adults. Considering its widespread therapeutic and potential preventive benefits, enzyme replacement therapy should be initiated at an early stage, prior to the onset of irreversible complications.

Adolescent↗
PubMed2002

Cardiac manifestations of Anderson-Fabry disease in heterozygous females.

OBJECTIVES: We sought to define the prevalence of cardiac involvement in female patients with Anderson-Fabry disease (AFD). BACKGROUND: Anderson-Fabry disease is a rare inborn X-linked lysosomal storage disorder. Globotriaosylceramide (Gb(3)), the major substrate of the deficient alpha-galactosidase A enzyme, accumulates progressively in vulnerable cells, including the cardiovascular system. It has been believed that heterozygous females have less cardiac involvement than hemizygous males with AFD. METHODS: We performed two-dimensional echocardiographic examinations of female patients heterozygous for AFD. RESULTS: Since 1997, a total of 55 female patients (mean age, 39.6 years; range, 6.1 to 70.8 years) with proven AFD have been investigated prospectively at our hospital. Of these, 13 (23.6%) had normal left ventricular (LV) geometry and LV mass (LVM). Seven patients (12.7%) had concentric remodeling, 29 patients (52.7%) concentric LV hypertrophy (LVH), and 6 patients (10.9%) eccentric LVH (2 with subaortic pressure gradients). There was a strong correlation between age and the severity of LVH (r(2) = 0.905; p < 0.0001), and all patients older than 45 years had LVH. With increasing LVM, there was a significant age-independent decrease in systolic and diastolic LV function. Mild thickening of the aortic valve leaflets was present in 25.5% of patients, with the same percentage demonstrating mild thickening of the mitral valve leaflets. Mild mitral valve prolapse was documented in 10.9% of patients. CONCLUSIONS: Cardiac involvement, with LVH and structural valve abnormalities, is very common and worsens with age in females who are heterozygous for AFD, and they should therefore be considered candidates for enzyme replacement therapy.

Adolescent↗