ABSTRACT
BACKGROUND: Fabry disease is a multisystemic lysosomal storage disorder caused by the impairment of α-galactosidase A. The incidence of this rare disease is underestimated due to delayed diagnosis. Moreover, the management of the identified subjects is often complicated by the detection of variants of unclear diagnostic interpretation, usually identified in screening studies. We performed an observational study based on biochemical and genetic analysis of 805 dried blood spot samples from patients with clinical symptoms or family history of this pathology, which were collected from 109 Spanish hospitals, all over the country. RESULTS: We identified 77 new diagnosed patients with mutations related to classical Fabry disease, as well as 2 subjects with c.374A > T; p.His125Leu, a possible new mutation that need to be confirmed. Additionally, we detected 8 subjects carrying genetic variants possibly linked to late onset Fabry disease (p.Arg118Cys and p.Ala143Thr), 4 cases with polymorphism p.Asp313Tyr and 36 individuals with single nucleotide polymorphisms in intronic regions of GLA. Five of the identified mutations (c.431delG; c.1182delA; c.374A > T; c.932 T > C; c.125 T > A; c.778G > A), which were associated with a classical phenotype have not been previously described. Moreover 3 subjects presenting complex haplotypes made up by the association of intronic variants presented impaired levels of GLA transcripts and Gb3 deposits in skin biopsy. CONCLUSIONS: Enzymatic screening for Fabry Disease in risk population (2 or more clinical manifestations or family history of the disease) helped to identify undiagnosed patients and unravel the impairment of GLA expression in some subjects with complex haplotypes.
Subject(s)
Fabry Disease/diagnosis , Fabry Disease/epidemiology , alpha-Galactosidase/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Fabry Disease/genetics , Female , Genetic Predisposition to Disease , Humans , Infant , Male , Middle Aged , Spain/epidemiology , Young AdultABSTRACT
BACKGROUND: Hepatorenal tyrosinaemia (Tyr 1) is a rare inborn error of tyrosine metabolism. Without treatment, patients are at high risk of developing acute liver failure, renal dysfunction and in the long run hepatocellular carcinoma. The aim of our study was to collect cross-sectional data. METHODS: Via questionnaires we collected retrospective data of 168 patients with Tyr 1 from 21 centres (Europe, Turkey and Israel) about diagnosis, treatment, monitoring and outcome. In a subsequent consensus workshop, we discussed data and clinical implications. RESULTS: Early treatment by NTBC accompanied by diet is essential to prevent serious complications such as liver failure, hepatocellular carcinoma and renal disease. As patients may remain initially asymptomatic or develop uncharacteristic clinical symptoms in the first months of life newborn mass screening using succinylacetone (SA) as a screening parameter in dried blood is mandatory for early diagnosis. NTBC-treatment has to be combined with natural protein restriction supplemented with essential amino acids. NTBC dosage should be reduced to the minimal dose allowing metabolic control, once daily dosing may be an option in older children and adults in order to increase compliance. Metabolic control is judged by SA (below detection limit) in dried blood or urine, plasma tyrosine (<400 µM) and NTBC-levels in the therapeutic range (20-40 µM). Side effects of NTBC are mild and often transient. Indications for liver transplantation are hepatocellular carcinoma or failure to respond to NTBC. Follow-up procedures should include liver and kidney function tests, tumor markers and imaging, ophthalmological examination, blood count, psychomotor and intelligence testing as well as therapeutic monitoring (SA, tyrosine, NTBC in blood). CONCLUSION: Based on the data from 21 centres treating 168 patients we were able to characterize current practice and clinical experience in Tyr 1. This information could form the basis for clinical practice recommendations, however further prospective data are required to underpin some of the recommendations.
Subject(s)
Cyclohexanones/therapeutic use , Enzyme Inhibitors/therapeutic use , Neonatal Screening/methods , Nitrobenzoates/therapeutic use , Tyrosinemias/diagnosis , Tyrosinemias/therapy , Adolescent , Child , Child, Preschool , Cross-Sectional Studies , Cyclohexanones/adverse effects , Enzyme Inhibitors/adverse effects , Female , Follow-Up Studies , Humans , Infant , Infant, Newborn , Liver Failure/diagnosis , Liver Failure/surgery , Liver Transplantation , Male , Nitrobenzoates/adverse effects , Rare Diseases/diagnosis , Rare Diseases/drug therapy , Renal Insufficiency/diagnosis , Renal Insufficiency/surgery , Retrospective Studies , Surveys and Questionnaires , Treatment Outcome , Young AdultABSTRACT
A girl, born to unrelated Spanish parents, presented at 6 months of age with photophobia, keratitis, palmar hyperkeratosis and high plasma tyrosine levels, indicative of tyrosinaemia type II. Analysis of the tyrosine aminotransferase (TAT) gene revealed a paternally inherited frameshift mutation c.1213delCinsAG at codon 405 causing a premature stop codon, and a maternally inherited deletion of 193kb encompassing the complete TAT gene and three neighbouring genes. This is the first complete TAT deletion in tyrosinaemia type II described so far.
Subject(s)
Gene Deletion , Tyrosine Transaminase/genetics , Tyrosinemias/genetics , Base Sequence , Codon, Nonsense , DNA Primers/genetics , Female , Frameshift Mutation/genetics , Humans , Infant , Molecular Sequence Data , Polymerase Chain Reaction , Sequence Analysis, DNA , SpainABSTRACT
BACKGROUND: Patients with phenylketonuria (PKU) undergo a restrictive vegan-like diet, with almost total absence of n-3 fatty acids, which have been proposed as potential contributors to bone formation in the healthy population. The PKU diet might lead these patients to bone mass loss and, consequently, to the development of osteopenia/osteoporosis. Therefore, we proposed to analyze their plasma fatty acid profile status and its relationship with bone health. METHODS: We recruited 47 PKU patients for this cross-sectional study and divided the cohort into three age groups (6-10 years, 11-18 years, 19-42 years). We measured their plasma fatty acid profile and bone mineral density (BMD) (both at the femoral neck and the lumbar spine). Seventy-seven healthy controls also participated as reference values of plasma fatty acids. RESULTS: Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) and total n-3 fatty acids were significantly diminished in PKU patients compared with healthy controls. DHA, EPA, and total n-3 fatty acids were also positively associated with bone mineral density (r = 0.83, p = 0.010; r = 0.57, p = 0.006; r = 0.73, p = 0.040, respectively). There was no association between phenylalanine (Phe), Index of Dietary Control (IDC), calcium, 25-hydroxivitamin D concentrations, daily calcium intake, and BMD. CONCLUSION: Our results suggest a possible influence of essential fatty acids over BMD in PKU patients. The lack of essential n-3 fatty acids intake in the PKU diet might affect bone mineralization. Further clinical trials are needed to confirm the effect of the n-3 essential fatty acids on bone accrual in a cohort of PKU patients.
