947 resultados para DISEASE PROGRESSION


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BACKGROUND: Hippocampal atrophy (HA) is a known predictor of dementia in Alzheimer's disease. HA has been found in advanced Parkinson's disease (PD), but no predicting value has been demonstrated yet. The identification of such a predictor in candidates for subthalamic deep brain stimulation (STN-DBS) would be of value. Our objective was to compare preoperative hippocampal volumes (HV) between PD patients who subsequently converted to dementia (PDD) after STN-DBS and those who did not (PDnD). METHODS: From a cohort of 70 consecutive STN-DBS treated PD patients, 14 converted to dementia over 25.6+/-20.2 months (PDD). They were compared to 14 matched controls (PDnD) who did not convert to dementia after 43.9+/-11.7 months. On the preoperative 3D MPRAGE MRI images, HV and total brain volumes (TBV) were measured by a blinded investigator using manual and automatic segmentation respectively. RESULTS: PDD had smaller preoperative HV than PDnD (1.95+/-0.29 ml; 2.28+/-0.33 ml; p<0.01). This difference reinforced after normalization for TBV (3.28+/-0.48, 3.93+/-0.60; p<0.01). Every 0.1 ml decrease of HV increased the likelihood to develop dementia by 24.6%. A large overlap was found between PD and PDnD HVs, precluding the identification of a cut-off score. CONCLUSIONS: As in Alzheimer's disease, HA may be a predictor of the conversion to dementia in PD. This preoperative predictor suggests that the development of dementia after STN-DBS is related to the disease progression, rather then the procedure. Further studies are needed to define a cut-off score for HA, in order to affine its predictive value for an individual patient.

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OBJECTIVE: To determine the association of changes on nailfold capillaroscopy with clinical findings and genotype in children with juvenile dermatomyositis (DM), in order to identify potential differences in disease course over 36 months. METHODS: At diagnosis of juvenile DM in 61 children prior to the initiation of treatment, tumor necrosis factor alpha (TNFalpha) -308 allele and DQA1*0501 status was determined, juvenile DM Disease Activity Scores (DAS) were obtained, and nailfold capillaroscopy was performed. The disease course was monitored for 36 months. Variations within and between patients were assessed by regression analysis. RESULTS: At diagnosis, shorter duration of untreated disease (P = 0.05) and a lower juvenile DM skin DAS (P = 0.035) were associated with a unicyclic disease course. Over 36 months, end-row loop (ERL) regeneration was associated with lower skin DAS (P &lt; 0.001) but not muscle DAS (P = 0.98); ERL regeneration and decreased bushy loops were associated with a shorter duration of untreated disease (P = 0.04 for both). At 36 months, increased ERL regeneration (P = 0.007) and improvement of skin DAS (P &lt; 0.001) and muscle DAS (P = 0.025) were associated with a unicyclic disease course. CONCLUSION: Early treatment of juvenile DM may lead to a unicyclic disease course. The non-unicyclic disease course usually involves continuing skin manifestations with persistent nailfold capillaroscopy changes. The correlation of nailfold capillaroscopy results with cutaneous but not with musculoskeletal signs of juvenile DM over a 36-month period suggests that the cutaneous and muscle vasculopathies have different pathophysiologic mechanisms. These findings indicate that efforts to identify the optimal treatment of cutaneous features in juvenile DM require greater attention.

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Susceptibility and development of Th2 cells in BALB/c mice infected with Leishmania major result from early IL-4 production by Vbeta4Valpha8 CD4+ T cells in response to the Leishmania homolog of mammalian RACK1 Ag. A role for CD4+CD25+ regulatory T cells in the control of this early IL-4 production was investigated by depleting in vivo this regulatory T cell population. Depletion induced an increase in the early burst of IL-4 mRNA in the draining lymph nodes of BALB/c mice, and exacerbated the course of disease with higher levels of IL-4 mRNA and protein in their lymph nodes. We further showed that transfer of 10(7) BALB/c spleen cells that were depleted of CD4+CD25+ regulatory T cells rendered SCID mice susceptible to infection and allowed Th2 differentiation while SCID mice reconstituted with 10(7) control BALB/c spleen cells were resistant to infection with L. major and developed a Th1 response. Treatment with a mAb against IL-4 upon infection with L. major in SCID mice reconstituted with CD25-depleted spleen cells prevented the development of Th2 polarization and rendered them resistant to infection. These results demonstrate that CD4+CD25+ regulatory T cells play a role in regulating the early IL-4 mRNA and the subsequent development of a Th2 response in this model of infection.

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BACKGROUND: The purpose of this study was to explore the potential use of image analysis on tissue sections preparation as a predictive marker of early malignant changes during squamous cell (SC) carcinogenesis in the esophagus. Results of DNA ploidy quantification on formalin-fixed, paraffin-embedded tissue using two different techniques were compared: imprint-cytospin and 6 microm thick tissue sections preparation. METHODS: This retrospective study included 26 surgical specimens of squamous cell carcinoma (SCC) from patients who underwent surgery alone at the Department of Surgery in CHUV Hospital in Lausanne between January 1993 and December 2000. We analyzed 53 samples of healthy tissue, 43 tumors and 7 lymph node metastases. RESULTS: Diploid DNA histogram patterns were observed in all histologically healthy tissues, either distant or proximal to the lesion. Aneuploidy was observed in 34 (79%) of 43 carcinomas, namely 24 (75%) of 32 early squamous cell carcinomas and 10 (91%) of 11 advanced carcinomas. DNA content was similar in the different tumor stages, whether patients presented with single or multiple synchronous tumors. All lymph node metastases had similar DNA content as their primary tumor. CONCLUSIONS: Early malignant changes in the esophagus are associated with alteration in DNA content, and aneuploidy tends to correlate with progression of invasive SCC. A very good correlation between imprint-cytospin and tissue section analysis was observed. Although each method used here showed advantages and disadvantages; tissue sections preparation provided useful information on aberrant cell-cycle regulation and helped select the optimal treatment for the individual patient along with consideration of other clinical parameters.

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The Drosophila transcription factor Prospero functions as a tumor suppressor, and it has been suggested that the human counterpart of Prospero, PROX1, acts similarly in human cancers. However, we show here that PROX1 promotes dysplasia in colonic adenomas and colorectal cancer progression. PROX1 expression marks the transition from benign colon adenoma to carcinoma in situ, and its loss inhibits growth of human colorectal tumor xenografts and intestinal adenomas in Apc(min/+) mice, while its transgenic overexpression promotes colorectal tumorigenesis. Furthermore, in intestinal tumors PROX1 is a direct and dose-dependent target of the beta-catenin/TCF signaling pathway, responsible for the neoplastic transformation. Our data underscore the complexity of cancer pathogenesis and implicate PROX1 in malignant tumor progression through the regulation of cell polarity and adhesion.

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BACKGROUND: We investigated changes in biomarkers of liver disease in HIV-HCV-coinfected individuals during successful combination antiretroviral therapy (cART) compared to changes in biomarker levels during untreated HIV infection and to HIV-monoinfected individuals. METHODS: Non-invasive biomarkers of liver disease (hyaluronic acid [HYA], aspartate aminotransferase-to-platelet ratio index [APRI], Fibrosis-4 [FIB-4] index and cytokeratin-18 [CK-18]) were correlated with liver histology in 49 HIV-HCV-coinfected patients. Changes in biomarkers over time were then assessed longitudinally in HIV-HCV-coinfected patients during successful cART (n=58), during untreated HIV-infection (n=59), and in HIV-monoinfected individuals (n=17). The median follow-up time was 3.4 years on cART. All analyses were conducted before starting HCV treatment. RESULTS: Non-invasive biomarkers of liver disease correlated significantly with the histological METAVIR stage (P<0.002 for all comparisons). The mean ±sd area under the receiver operating characteristic (AUROC) curve values for advanced fibrosis (≥F3 METAVIR) for HYA, APRI, FIB-4 and CK-18 were 0.86 ±0.05, 0.84 ±0.08, 0.80 ±0.09 and 0.81 ±0.07, respectively. HYA, APRI and CK-18 levels were higher in HIV-HCV-coinfected compared to HIV-monoinfected patients (P<0.01). In the first year on cART, APRI and FIB-4 scores decreased (-35% and -33%, respectively; P=0.1), mainly due to the reversion of HIV-induced thrombocytopaenia, whereas HYA and CK-18 levels remained unchanged. During long-term cART, there were only small changes (<5%) in median biomarker levels. Median biomarker levels changed <3% during untreated HIV-infection. Overall, 3 patients died from end-stage liver disease, and 10 from other causes. CONCLUSIONS: Biomarkers of liver disease highly correlated with fibrosis in HIV-HCV-coinfected individuals and did not change significantly during successful cART. These findings suggest a slower than expected liver disease progression in many HIV-HCV-coinfected individuals, at least during successful cART.

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BACKGROUND: There is an ever-increasing volume of data on host genes that are modulated during HIV infection, influence disease susceptibility or carry genetic variants that impact HIV infection. We created GuavaH (Genomic Utility for Association and Viral Analyses in HIV, http://www.GuavaH.org), a public resource that supports multipurpose analysis of genome-wide genetic variation and gene expression profile across multiple phenotypes relevant to HIV biology. FINDINGS: We included original data from 8 genome and transcriptome studies addressing viral and host responses in and ex vivo. These studies cover phenotypes such as HIV acquisition, plasma viral load, disease progression, viral replication cycle, latency and viral-host genome interaction. This represents genome-wide association data from more than 4,000 individuals, exome sequencing data from 392 individuals, in vivo transcriptome microarray data from 127 patients/conditions, and 60 sets of RNA-seq data. Additionally, GuavaH allows visualization of protein variation in ~8,000 individuals from the general population. The publicly available GuavaH framework supports queries on (i) unique single nucleotide polymorphism across different HIV related phenotypes, (ii) gene structure and variation, (iii) in vivo gene expression in the setting of human infection (CD4+ T cells), and (iv) in vitro gene expression data in models of permissive infection, latency and reactivation. CONCLUSIONS: The complexity of the analysis of host genetic influences on HIV biology and pathogenesis calls for comprehensive motors of research on curated data. The tool developed here allows queries and supports validation of the rapidly growing body of host genomic information pertinent to HIV research.

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BACKGROUND: Decreased vitamin D levels have been described in various forms of chronic liver disease and associated with advanced fibrosis. Whether this association is a cause or consequence of advanced fibrosis remains unclear to date. AIMS: To analyse combined effects of 25-OH vitamin D plasma levels and vitamin D receptor gene (VDR; NR1I1) polymorphisms on fibrosis progression rate in HCV patients. METHODS: 251 HCV patients underwent VDR genotyping (bat-haplotype: BsmI rs1544410 C, ApaI rs7975232 A and TaqI rs731236 A). Plasma 25-OH vitamin D levels were quantified in a subgroup of 97 patients without advanced fibrosis. The VDR haplotype and genotypes as well as plasma 25-OH vitamin D levels were associated with fibrosis progression. RESULTS: The bAt[CCA]-haplotype was significantly associated with fibrosis progression >0.101 U/year (P = 0.007; OR = 2.02) and with cirrhosis (P = 0.022; OR = 1.84). Forty-five percent of bAt[CCA]-haplotype patients were rapid fibrosers, 21.1% were cirrhotic. Likewise, ApaI rs7975232 CC genotype was significantly associated with fibrosis progression and cirrhosis. Lower plasma 25-OH vitamin D levels were significantly associated with fibrosis progression >0.101 U/year in F0-2 patients (P = 0.013). Combined analysis of both variables revealed a highly significant additive effect on fibrosis progression with 45.5% rapid fibrosers for bAt[CCA]-haplotype and 25-OH vitamin D < 20 μg/L compared with only 9.1% for the most favourable combination (P = 0.006). In multivariate analysis, the bAt-haplotype was an independent risk factor for fibrosis progression (P = 0.001; OR = 2.83). CONCLUSION: Low 25-OH vitamin D plasma levels and the unfavourable VDR bAt[CCA]-haplotype are associated with rapid fibrosis progression in chronic HCV patients. In combination, both variables exert significant additive effects on fibrosis progression.

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Résumé : La majorité des souches de souris de laboratoire sont résistantes à l'infection par le parasite Leishmania major (L. major). A l'opposé, les souris de la souche BALB développent une maladie évolutive. La résistance et la sensibilité sont corrélées avec l'apparition de lymphocytes T CD4+ spécifiques du parasite, Th1 (de l'anglais T helper) ou Th2 respectivement. La réponse aberrante Th2 chez les souris de la souche BALB/c dépend, au moins en partie, de façon critique de la production rapide d'IL-4 suite à l'infection. Ce pic précoce d'IL-4 est produit par une population de lymphocytes T CD4+ restreinte aux molécules du MHC de classe II, exprimant les chaînes du récepteur des cellules T Vß4-Va8. Ces lymphocytes sont spécifiques d'un épitope de l'homologue Leishmania de la molécule RACK1 des mammifères, appelée LACK. Il a été clairement démontré que l'IL-4 rapidement produite par ces cellules T CD4+ Vß4-Va8 induit la maturation Th2 responsable de la sensibilité vis-à-vis de L. major. Des expériences ont été entreprises pour étudier la régulation de cette réponse précoce d'IL-4. Dans ce travail, nous avons documenté, dans les cellules provenant des ganglions de souris sensibles infectées par L. major, une augmentation de la transcription de l'ARNm de l'IL-2 qui précède la réponse précoce d'IL-4. La neutralisation de l'IL-2 durant les premiers jours d'infection induit la maturation des cellules Thl et la résistance vis-à-vis de L. major. Ces effets de l'anticorps anti-IL-2 neutralisant sont liés à sa capacité d'interférer avec la transcription rapide d'IL-4 des cellules CD4+ réactives à l'antigène LACK. Une augmentation similaire d'IL-2 survient chez les souris résistantes C57BL/6 qui sont incapables de générer la réponse précoce d'IL-4. Cependant, la protéiné LACK induit une transcription précoce d'IL-2 uniquement chez les souris sensibles. Des expériences de reconstitution utilisant des souris C.B.-17 SCID et des cellules T CD4+ réactives à LACK provenant de souris BALB/c IL-2-~démontrent un mode d'action autocrine de l'IL-2 sur la régulation de la réponse précoce d'IL4. Par conséquent, chez les souris C57BL/6, l'absence du pic précoce d'ARNm de l'IL-4 important pour la progression de la maladie paraît liée à l'incapacité des cellules T CD4+ réactives à LACK de produire de l'IL-2. Un rôle dans le contrôle de la production précoce d'IL-4 par les cellules T régulatrices CD4+CD25+ a été investigué en déplétant in vivo cette population de cellules. La déplétion induit une élévation du pic précoce de l'ARNm de l'IL-4 dans les ganglions drainant de souris BALB/c, ainsi qu'une exacerbation du cours de la maladie avec des taux augmentés d'IL-4 dans les ganglions. La réponse rapide d'IL-2 vis-à-vis de L. major est aussi significativement augmentée chez les souris BALB/c déplétées en cellules CD4+CD25+. De plus, nous avons démontré que le transfert de 10puissance(7) cellules provenant de la rate de souris BALB/c déplétées en cellules T régulatrices CD4+CD25+ rend les souris SCID sensibles à l'infection et permet la différentiation Th2. Au contraire, les souris SCID reconstituées avec 10' cellules de la rate de souris BALB/c contrôle sont résistantes à infection par L. major et développent une réponse Thl. Chez les souris SCID reconstituées avec des cellules de rate déplétées en cellules exprimant le marqueur CD25, le traitement avec un anticorps neutralisant l'IL-4 au moment de l'infection par L. major prévient le développement de la réponse Th2 et rend ces souris résistantes à l'infection. Ces résultats démontrent que les cellules T régulatrices CD4+CD25+ jouent un rôle dans la régulation du pic précoce d'IL-4 responsable du développement cellulaire Th2 dans ce modèle d'infection. Summary Mice from most strains are resistant to infection with Leishmania major (L. major). In contrast, BALB mice develop progressive disease. Resistance and susceptibility result from parasite-specific CD4+ Thl or Th2 cells, respectively. The aberrant Th2 response in BALB/c mice depends, at least in part, upon the production of IL-4 early after infection. The CD4+ T cells responsible for this early IL-4 response to L. major express a restricted TCR repertoire (Vß4-Va8) and respond to an I-Ad-restricted epitope of the Leishmania homologue of mammalian RACK1, designated LACK. The role of these cells and the IL-4 they produce for subsequent Th2 cell development and disease progression in BALB/c mice was demonstrated. Experiments have been undertaken to study the regulation of the rapid IL-4 production to L. major. In this report, we document an IL-2 mRNA burst, preceding the reported early IL-4 response, in draining lymph nodes of susceptible mice infected with L. major. Neutralization of IL-2 during the first days of infection redirected Thl cell maturation and resistance to L. major, through interference with the rapid IL-4 transcription in LACKreactive CD4+ cells. A burst of IL-2 transcripts also occurred in infected C57BL/6 mice that do not mount an early IL-4 response. However, although the LACK protein induced IL-2 transcripts in susceptible mice, it failed to trigger this response in resistant C57BL/6 mice. Reconstitution experiments using C.B.-17 SCID mice and LACK-reactive CD4+ T cells from IL-2-/- BALB/c mice showed that triggering of the early IL-4 response required autocrine IL2. Thus, in C57BL/6 mice, the inability of LACK-reactive CD4+ T cells to express early IL-4 mRNA transcription, important for disease progression, appears due to an incapacity of these cells to produce IL-2. A role for CD4+CD25+ regulatory T cells in the control of this early IL-4 production was investigated by depleting in vivo this regulatory T cell population. Depletion induced an increase in the early burst of IL-4 mRNA in the draining lymph nodes of BALB/c mice, and exacerbated the course of disease with higher levels of IL-4 mRNA and protein in their lymph nodes. The rapid IL-2 response to L. major is also significantly enhanced in BALB/c mice depleted of CD4+CD25+ cells. We further showed that transfer of 10~ BALB/c spleen cells that were depleted of CD4+CD25+ regulatory T cells rendered SCID mice susceptible to infection and allowed Th2 differentiation while SCID mice reconstituted with 10 control BALB/c spleen cells were resistant to infection with L. major and developed a Thl response. Treatment with a mAb against IL-4 upon infection with L. major in SCID mice reconstituted with CD25-depleted spleen cells prevented the development of Th2 polarization and rendered them resistant to infection. These results demonstrate that CD4+CD25+ regulatory T cells play a role in regulating the early IL-4 mRNA and the subsequent development of a Th2 response in this model of infection.

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Interstitial lung disease (ILD) is found in up to 30% of patients with rheumatoid arthritis (RA) and is clinically manifest in 5 to 10%, resulting in significant morbidity and mortality. The most frequent histopathological forms are usual interstitial pneumonia and nonspecific interstitial pneumonia. Another recently described presentation is combined pulmonary fibrosis and emphysema. Similarly to idiopathic pulmonary fibrosis, acute exacerbation of ILD may occur in RA and is associated with severe prognosis. Smoking is a known risk factor of RA and may also play a role in the pathogenesis of RA-associated ILD, in combination with genetic and immunologic mechanisms. Several treatments of RA may also lead to drug-induced ILD.

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T helper type 17 (Th17) cells play an important pathogenic function in autoimmune diseases; their regulation, however, is not well understood. We show that the expression of a tumor necrosis factor receptor family member, death receptor 3 (DR3; also known as TNFRSF25), is selectively elevated in Th17 cells, and that TL1A, its cognate ligand, can promote the proliferation of effector Th17 cells. To further investigate the role of the TL1A-DR3 pathway in Th17 regulation, we generated a TL1A-deficient mouse and found that TL1A(-/-) dendritic cells exhibited a reduced capacity in supporting Th17 differentiation and proliferation. Consistent with these data, TL1A(-/-) animals displayed decreased clinical severity in experimental autoimmune encephalomyelitis (EAE). Finally, we demonstrated that during EAE disease progression, TL1A was required for the optimal differentiation as well as effector function of Th17 cells. These observations thus establish an important role of the TL1A-DR3 pathway in promoting Th17 cell function and Th17-mediated autoimmune disease.

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The cytosine deaminase APOBEC3G, in the absence of the human immunodeficiency virus type 1 (HIV-1) accessory gene HIV-1 viral infectivity factor (vif), inhibits viral replication by introducing G-->A hypermutation in the newly synthesized HIV-1 DNA negative strand. We tested the hypothesis that genetic variants of APOBEC3G may modify HIV-1 transmission and disease progression. Single nucleotide polymorphisms were identified in the promoter region (three), introns (two), and exons (two). Genotypes were determined for 3,073 study participants enrolled in six HIV-AIDS prospective cohorts. One codon-changing variant, H186R in exon 4, was polymorphic in African Americans (AA) (f = 37%) and rare in European Americans (f < 3%) or Europeans (f = 5%). For AA, the variant allele 186R was strongly associated with decline in CD4 T cells (CD4 slope on square root scale: -1.86, P = 0.009), The 186R allele was also associated with accelerated progression to AIDS-defining conditions in AA. The in vitro antiviral activity of the 186R enzyme was not inferior to that of the common H186 variant. These studies suggest that there may be a modifying role of variants of APOBEC3G on HIV-1 disease progression that warrants further investigation.

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Endometriosis, a leading cause of pelvic pain and infertility, is characterized by ectopic growth of endometrial-like tissue and affects approximately 176 million women worldwide. The pathophysiology involves inflammatory and angiogenic mediators as well as estrogen-mediated signaling and novel, improved therapeutics targeting these pathways are necessary. The aim of this study was to investigate mechanisms leading to the establishment and progression of endometriosis as well as the effect of local treatment with Lipoxin A4 (LXA₄), an anti-inflammatory and pro-resolving lipid mediator that we have recently characterized as an estrogen receptor agonist. LXA₄ treatment significantly reduced endometriotic lesion size and downregulated the pro-inflammatory cytokines IL-1β and IL-6, as well as the angiogenic factor VEGF. LXA₄ also inhibited COX-2 expression in both endometriotic lesions and peritoneal fluid cells, resulting in attenuated peritoneal fluid Prostaglandin E₂ (PGE₂) levels. Besides its anti-inflammatory effects, LXA₄ differentially regulated the expression and activity of the matrix remodeling enzyme matrix metalloproteinase (MMP)-9 as well as modulating transforming growth factor (TGF)-β isoform expression within endometriotic lesions and in peritoneal fluid cells. We also report for first time that LXA₄ attenuated aromatase expression, estrogen signaling and estrogen-regulated genes implicated in cellular proliferation in a mouse model of disease. These effects were observed both when LXA₄ was administered prior to disease induction and during established disease. Collectively, our findings highlight potential targets for the treatment of endometriosis and suggest a pleotropic effect of LXA₄ on disease progression, by attenuating pro-inflammatory and angiogenic mediators, matrix remodeling enzymes, estrogen metabolism and signaling, as well as downstream proliferative pathways.

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In each case of extraintestinal manifestations of Crohn's disease, active disease, if present, should be treated to induce remission, which may positively influence the course of most concomitant extraintestinal manifestations. For some extraintestinal manifestations, however, a specific treatment should be introduced. This latter part of disease management will be discussed in this chapter, in particular for pyoderma gangrenosum, uveitis, spondylarthropathy--axial arthropathy--and primarysclerosing cholangitis, which have also been described in quiescent Crohn's disease. Few new drugs for the treatment of extraintestinal manifestations of Crohn's disease have been developed in the past and only the role of infliximab has increased in Crohn's disease-related extraintestinal manifestations. Drugs specifically aimed at this treatment, stemming from a few randomized controlled studies or case series, are sulfasalazine, 5-ASA, corticosteroids, azathioprine or 6-mercaptopurine, methotrexate, infliximab, dapsone and cyclosporine or tacrolimus.

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Purpose: Wolfram syndrome is a degenerative, recessive rare disease with an onset in childhood. It is caused by mutations in WFS1 or CISD2 genes. More than 200 different variations in WFS1 have been described in patients with Wolfram syndrome, which complicates the establishment of clear genotype-phenotype correlation. The purpose of this study was to elucidate the role of WFS1 mutations and update the natural history of the disease. Methods: This study analyzed clinical and genetic data of 412 patients with Wolfram syndrome published in the last 15 years. Results: (i) 15% of published patients do not fulfill the current ­inclusion criterion; (ii) genotypic prevalence differences may exist among countries; (iii) diabetes mellitus and optic atrophy might not be the first two clinical features in some patients; (iv) mutations are nonuniformly distributed in WFS1; (v) age at onset of diabetes mellitus, hearing defects, and diabetes insipidus may depend on the patient"s genotypic class; and (vi) disease progression rate might depend on genotypic class. Conclusion: New genotype-phenotype correlations were established, disease progression rate for the general population and for the genotypic classes has been calculated, and new diagnostic criteria have been proposed. The conclusions raised could be important for patient management and counseling as well as for the development of treatments for Wolfram syndrome.