Hurler disease (mucopolysaccharidosis type IH): clinical features and consanguinity in Tunisian population

Mucopolysaccharidosis type I (MPS I) was a group of rare autosomal recessive disorder caused by the deficiency of the lysosomal enzyme, alpha -L -iduronidase, and the resulting accumulation of undergraded dematan sulfate and heparan sulfate. MPS I patients have a wide range of clinical presentations, that makes it difficult to predict patient phenotype which is needed for genetic counseling and also impedes the selection and evaluation of patients undergoing therapy bone marrow transplantation

Mucopolysaccharidosis type I: molecular characteristics of two novel alpha-L-iduronidase mutations in Tunisian patients

<p>Abstract</p> <p>Background</p> <p>Mucopolysaccharidosis type I (MPS I) is an autosomal storage disease resulting from defective activity of the enzyme α-L-iduronidase (IDUA). This glycosidase is involved in the degradation of heparan sulfate and dermatan sulfate. MPS I has severe and milder phenotypic subtypes.</p> <p>Aim of study: This study was carried out on six newly collected MPS I patients recruited from many regions of Tunisia.</p> <p>Patients and methods: Mutational analysis of the IDUA gene in unrelated MPS I families was performed by sequencing the exons and intron-exon junctions of IDUA gene.</p> <p>Results</p> <p>Two novel IDUA mutations, p.L530fs (1587_1588 insGC) in exon 11 and p.F177S in exon 5 and two previously reported mutations p.P533R and p.Y581X were detected. The patient in family 1 who has the Hurler phenotype was homozygous for the previously described nonsense mutation p.Y581X.</p> <p>The patient in family 2 who also has the Hurler phenotype was homozygous for the novel missense mutation p.F177S. The three patients in families 3, 5 and 6 were homozygous for the p.P533R mutation. The patient in family 4 was homozygous for the novel small insertion 1587_1588 insGC. In addition, eighteen known and one unknown IDUA polymorphisms were identified.</p> <p>Conclusion</p> <p>The identification of these mutations should facilitate prenatal diagnosis and counseling for MPS I in Tunisia.</p> <p>Background</p> <p>Mucopolysaccharidosis type I (MPS I) is an autosomal recessive lysosomal storage disorder caused by the deficient activity of the enzyme of α-L-iduronidase (IDUA, EC 3.2.1.76). This glycosidase is involved in the degradation of heparan sulfate and dermatan sulfate. The clinical phenotype of MPS I ranges from the very severe in Hurler syndrome (MPS IH) to the relatively benign in Scheie syndrome (MPS IS), with an intermediate phenotype designated Hurler/Scheie (MPS IH/S) <abbrgrp><abbr bid="B1">1</abbr></abbrgrp>. Isolation of complementary and genomic DNAs encoding human α -L- iduronidase <abbrgrp><abbr bid="B2">2</abbr><abbr bid="B3">3</abbr></abbrgrp> have enable the identification of mutations underlying the enzyme defect and resulting in MPS I clinical phenotype. More than 100 mutations have been reported in patients with the MPS I subtypes (Human Gene Mutation Database; <url>http://www.hgmd.org</url>). High prevalence of the common mutations p.W402X and p.Q70X has been described; both of them in the severe clinical forms <abbrgrp><abbr bid="B4">4</abbr><abbr bid="B5">5</abbr></abbrgrp>. A high prevalence of common mutation p.P533R has also been described in MPS I patients with various phenotypes <abbrgrp><abbr bid="B5">5</abbr><abbr bid="B6">6</abbr></abbrgrp>. In addition, rare mutations including single base substitution, deletion, insertion and splicing site mutation have been identified <abbrgrp><abbr bid="B7">7</abbr></abbrgrp>, indicating a high degree of allelic heterogeneity in IDUA gene.</p> <p>Here, we described two novel IDUA mutations in MPS I Tunisian patients. These lesions were homoallelic in all the patients of the six families investigated as consanguineous marriages are still frequent in Tunisia <abbrgrp><abbr bid="B8">8</abbr></abbrgrp>.</p

HIVAN and medication use in chronic dialysis patients in the United States: analysis of the USRDS DMMS Wave 2 study

BACKGROUND: The use and possible effects of factors known to improve outcomes in patients with human immunodeficiency virus associated nephropathy (HIVAN), namely of angiotensin converting enzyme inhibitors (ACE) and antiretroviral therapy, has not been reported for a national sample of dialysis patients. METHODS: We conducted a historical cohort study of the United States Renal Data System (USRDS) Dialysis Morbidity and Mortality Study (DMMS) Wave 2 to identify risk factors associated with increased mortality in these patients. Data were available for 3374 patients who started dialysis and were followed until March 2000. Cox Regression analysis was used to model adjusted hazard ratios (AHR) with HIVAN as a cause of end stage renal disease (ESRD) and its impact on mortality during the study period, adjusted for potential confounders. RESULTS: Of the 3374 patients who started dialysis, 36 (1.1%) had ESRD as a result of HIVAN. Only 22 (61%) of patients with HIVAN received antiretroviral agents, and only nine patients (25%) received combination antiretroviral therapy, and only 14% received ACE inhibitors. Neither the use of multiple antiretroviral drugs (AHR, 0.62, 95% CI, 0.10, 3.86, p = 0.60), or ACE inhibitors were associated with a survival advantage. Patients with HIVAN had an increased risk of mortality (adjusted hazard ratio, 4.74, 95% Confidence Interval, 3.12, 7.32, p < 0.01) compared to patients with other causes of ESRD. CONCLUSIONS: Medications known to improve outcomes in HIV infected patients were underutilized in patients with HIVAN. Adjusted for other factors, a primary diagnosis of HIVAN was associated with increased mortality compared with other causes of ESRD

Understanding factors affecting social commerce purchase behavior: a longitudinal perspective

The use of social media has experienced a surge in popularity globally in recent years, with a rapidly increasing rate of adoption. Retailers are experimenting with various strategies to promote their products and services to customers, taking advantage of the popularity of these websites. Nevertheless, there is significant controversy within the scholarly and practitioners regarding the main motivations of consumers purchase behavior in the social commerce (SC) setting, as well as the effective techniques that may make them a viable alternative for future business endeavors. Drawing upon value motivation theory and prior research on privacy/security in the SC setting, our study developed an integrated model to understand the impact of utilitarian value, hedonic value, perceived privacy/security, and trust at social commerce platform (SCP) on purchase intentions via social media over time. This study employed two-wave data (“T = 736 and T+1 = 601”) and used the “cross-lagged panel” technique to analyze the “longitudinal data”. The results of this study offer meaningful insights about the cause-and-effect relationship and significant effect of utilitarian value, hedonic value, and perceived privacy/security on consumer trust and purchase intentions. Furthermore, it suggests that customer trust plays a mediating role on these relationships over time. This study offers meaningful implication for theory and practice

How to mitigate the risk of inducing transfusion-associated adverse reactions.

Transfusion has become extremely safe but can still be associated with adverse reactions. Some adverse reactions can be mitigated by applying measures to donor selection, the process of separating blood components as well as hospital-based procedures consisting in matching the donor and the recipient; special attention is given to optimizing the best fit between the component and the beneficiary, which is not only an immuno-hematological challenge (fresh versus old blood, testing for certain viruses such as CMV, parvovirus B19, etc.). Considerable progress has also been achieved to strengthen the overall quality and safety of the whole transfusion chain. Guidelines and recommendations have resulted in substantial progress, and the recent revisiting of patients as part of a more holistic approach has enabled blood management programs to be created. Such programs, when wisely applied in a context of optimal blood use, reinforce patient safety; they enhance hospital recognition of transfusion and hemovigilance specialists as useful players acting in the interests of patients in full compliance with hospital budgets. This review considers the step-by-step processes that reinforce transfusion safety and identifies hurdles that cannot yet be properly addressed; it proposes steps for further progress, in light of personalized medicine

Genetic Heterogeneity of 72 Patients With Mucopolysaccharidosis In Tunisia

The mucopolysaccharidoses (MPS) are a group of lysosomal storage diseases, presenting with a progressive multisystem disorder, with extreme clinical heterogeneity. The purpose of this study was to investigate six genes involved in different types of mucopolysaccharidosis (MPS), a group of lysosomal storage diseases. Mutation screening was performed for a total of 72 MPS Tunisian patients with MPS I (n=43), MPS II (n=5), MPS IIIA (n=7), MPS IIIB (n=3), MPS IIIC (n=2), or MPS IVA (n=12). The methodological approaches included genomic PCR sequencing, RT-PCR for MPS IVA and tetra-primer ARMS PCR assay for MPSI. The present study revealed one novel splice site mutation in one MPSI patient, in addition to the 11 previously Tunisian mutations reported for the first time by our research team: three in the IDUA gene (MPS I) including two missense, one nonsense four in the SGSH gene (MPS IIIA) including a mutation involving the start codon, one small duplication, one small deletion and a large deletion of exons 1 to 5 two in the NAGLU gene (MPS IIIB) including one missense mutation and one nonsense mutation two in the HGSNAT gene (MPS IIIC) including one missense and one nonsense mutation, two in the GALNS gene including one missense and one splicing mutation. These data demonstrate the remarkable mutational heterogeneity characterizing all types of MPS tested, although high consanguinity rate in the Tunisian population. We report biochemical and molecular aspects of these patients to prevent (e.g. genetic counseling, prenatal diagnosis) the recurrence of affected child since these diseases are still not rare in our area and as specific therapy is not available in our country. nbs