Francesco Emma

Ospedale Pediatrico Bambino Gesù, Roma, Latium, Italy

Are you Francesco Emma?

Claim your profile

Publications (131)596.73 Total impact

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Defective primary ciliogenesis or cilium stability forms the basis of human ciliopathies, including Joubert syndrome (JS), with defective cerebellar vermis development. We performed a high-content genome-wide siRNA screen to identify genes regulating ciliogenesis as candidates for JS. We analyzed results with a supervised-learning approach, using SYSCILIA gold standard, Cildb3.0, a centriole siRNA screen and the GTex project, identifying 591 likely candidates. Intersection of this data with whole exome results from 145 individuals with unexplained JS identified six families with predominantly compound heterozygous mutations in KIAA0586. A c.428del base deletion in 0.1% of the general population was found in trans with a second mutation in an additional set of 9 of 163 unexplained JS patients. KIAA0586 is an orthologue of chick Talpid3, required for ciliogenesis and sonic hedgehog signaling. Our results uncover a relatively high frequency cause for JS and contribute a list of candidates for future gene discoveries in ciliopathies.
    eLife Sciences 05/2015; 4. DOI:10.7554/eLife.06602.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Cystinosis is a rare autosomal recessive disease caused by mutations of the CTNS gene, which encodes for a lysosomal cystine/H(+) symporter. In mice, inactivation of the CTNS gene causes intralysosomal cystine accumulation and progressive organ damage that can be reversed, at least in part, by infusion of mesenchymal stromal cells (MSCs). Little is known on the mesenchymal compartment of cystinotic patients. The aim of the study was to test the phenotypical and functional properties of cystinotic MSCs (Cys-MSCs) isolated from bone marrow (BM) aspirate of a patient with nephropathic cystinosis. Morphology, proliferative capacity (measured as population doublings), immunophenotype (by flow-cytometry) and immunomodulatory properties (as phytohemagglutinin-induced peripheral blood mononuclear cell proliferation) were analyzed. The osteogenic differentiation potential of Cys-MSCs was evaluated by histological staining (alkaline phosphatase activity, Alzarin Red and von Kossa staining) spectrophotometry and Quantitative Reverse Transcriptase Polymerase Chain Reaction for osteigenic markers in the presence and in the absence of cysteamine. Cys-MSCs were compared with those isolated and expanded ex vivo from three healthy donors (HD-MSCs). Despite a slightly lower proliferative capacity, Cys-MSCs displayed a characteristic spindle-shaped morphology and similar immunephenotype as HD-MSCs. Cys-MSCs and HD-MSCs prevented proliferation of PHA-stimulated allogeneic peripheral blood mononuclear cells to the same extent. After in vitro induction into osteoblasts, Cys-MSCs showed reduced alkaline phosphatase (ALP) activity, calcium depositions and expression of ALP and collagen type 1. When Cys-MSCs were treated in vitro with increasing doses of cysteamine (50-100-200 μM/L) during the differentiation assay, recovery of Cys-MSCs differentiation capacity into osteoblasts was observed. No difference in adipogenic differentiation was found between Cys-MSCs and HD-MSCs. Our results indicate that, as compared to HD-MSCs, Cys-MSCs show reduced ability to differentiate into osteoblasts, which can be reverted after cysteamine treatment.
    Journal of Translational Medicine 05/2015; 13(1):143. DOI:10.1186/s12967-015-0494-0
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Dent disease is a rare X-linked tubulopathy characterised by low molecular weight proteinuria (LMWP), hypercalciuria, nephrocalcinosis and/or nephrolithiasis, progressive renal failure and variable manifestations of other proximal tubule dysfunctions. It often progresses over a few decades to chronic renal insufficiency, and therefore molecular characterization is important to allow appropriate genetic counselling. Two genetic subtypes have been described to date: Dent disease 1 is caused by mutations of the CLCN5 gene, coding for the chloride/proton exchanger ClC-5; and Dent disease 2 by mutations of the OCRL gene, coding for the inositol polyphosphate 5-phosphatase OCRL-1. Herein, we review previously reported mutations (n = 192) and their associated phenotype in 377 male patients with Dent disease 1 and describe phenotype and novel (n = 42) and recurrent mutations (n = 24) in a large cohort of 117 Dent disease 1 patients belonging to 90 families. The novel missense and in-frame mutations described were mapped onto a three-dimensional homology model of the ClC-5 protein. This analysis suggests that these mutations affect the dimerization process, helix stability or transport. The phenotype of our cohort patients supports and extends the phenotype that has been reported in smaller studies. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    Human Mutation 04/2015; DOI:10.1002/humu.22804
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Steroid-resistant nephrotic syndrome is a rare kidney disease involving either immune-mediated or genetic alterations of podocyte structure and function. The rare nature, heterogeneity, and slow evolution of the disorder are major obstacles to systematic genotype-phenotype, intervention, and outcome studies, hampering the development of evidence-based diagnostic and therapeutic concepts. To overcome these limitations, the PodoNet Consortium has created an international registry for congenital nephrotic syndrome and childhood-onset steroid-resistant nephrotic syndrome. Since August of 2009, clinical, biochemical, genetic, and histopathologic information was collected both retrospectively and prospectively from 1655 patients with childhood-onset steroid-resistant nephrotic syndrome, congenital nephrotic syndrome, or persistent subnephrotic proteinuria of likely genetic origin at 67 centers in 21 countries through an online portal. Steroid-resistant nephrotic syndrome manifested in the first 5 years of life in 64% of the patients. Congenital nephrotic syndrome accounted for 6% of all patients. Extrarenal abnormalities were reported in 17% of patients. The most common histopathologic diagnoses were FSGS (56%), minimal change nephropathy (21%), and mesangioproliferative GN (12%). Mutation screening was performed in 1174 patients, and a genetic disease cause was identified in 23.6% of the screened patients. Among 14 genes with reported mutations, abnormalities in NPHS2 (n=138), WT1 (n=48), and NPHS1 (n=41) were most commonly identified. The proportion of patients with a genetic disease cause decreased with increasing manifestation age: from 66% in congenital nephrotic syndrome to 15%-16% in schoolchildren and adolescents. Among various intensified immunosuppressive therapy protocols, calcineurin inhibitors and rituximab yielded consistently high response rates, with 40%-45% of patients achieving complete remission. Confirmation of a genetic diagnosis but not the histopathologic disease type was strongly predictive of intensified immunosuppressive therapy responsiveness. Post-transplant disease recurrence was noted in 25.8% of patients without compared with 4.5% (n=4) of patients with a genetic diagnosis. The PodoNet cohort may serve as a source of reference for future clinical and genetic research in this rare but significant kidney disease. Copyright © 2015 by the American Society of Nephrology.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Alloimmune antenatal membranous nephropathy (MN) during pregnancy results from antibodies produced by a neutral endopeptidase (NEP)-deficient mother. Here we report two recent cases that provide clues to the severity of renal disease. Mothers of the two children had circulating antibodies against NEP showing the characteristic species-dependent pattern by immunofluorescence on kidney slices. A German mother produced predominantly anti-NEP IgG4 accompanied by a low amount of IgG1. Her child recovered renal function within a few weeks. In sharp contrast, an Italian mother mainly produced complement-fixing anti-NEP IgG1, which also inhibits NEP enzymatic activity, whereas anti-NEP IgG4 has a weak inhibitory potency. Her child was dialyzed for several weeks. A kidney biopsy performed at 12 days of age showed MN, ischemic glomeruli, and arteriolar and tubular lesions. A second biopsy performed at 12 weeks of age showed aggravation with an increased number of collapsed capillary tufts. Both mothers were homozygous for the truncating deletion mutation 466delC and were thus NEP deficient. The 466delC mutation, identified in three previously described families, suggests a founder effect. Because of the potential severity of alloimmune antenatal MN, it is essential to identify families at risk by the detection of anti-NEP antibodies and NEP antigen in urine. On the basis of the five families identified to date, we propose an algorithm for the diagnosis of the disease and the prevention of complications.Kidney International advance online publication, 7 January 2015; doi:10.1038/ki.2014.381.
    Kidney International 01/2015; 87(3). DOI:10.1038/ki.2014.381
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Human serum IgM Abs are composed of heavily glycosylated polymers with five glycosylation sites on the μ (heavy) chain and one glycosylation site on the J chain. In contrast to IgG glycans, which are vital for a number of biological functions, virtually nothing is known about structure-function relationships of IgM glycans. Natural IgM is the earliest Ig produced and recognizes multiple Ags with low affinity, whereas immune IgM is induced by Ag exposure and is characterized by a higher Ag specificity. Natural anti-lymphocyte IgM is present in the serum of healthy individuals and increases in inflammatory conditions. It is able to inhibit T cell activation, but the underlying molecular mechanism is not understood. In this study, to our knowledge, we show for the first time that sialylated N-linked glycans induce the internalization of IgM by T cells, which in turn causes severe inhibition of T cell responses. The absence of sialic acid residues abolishes these inhibitory activities, showing a key role of sialylated N-glycans in inducing the IgM-mediated immune suppression. Copyright © 2014 by The American Association of Immunologists, Inc.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background Hereditary tyrosinemia type 1 (HT1) is characterized by severe progressive liver disease and renal tubular dysfunction. NTBC therapy has revolutionized the management of HT1 but its effect on renal tubular function has so far been poorly investigated. Aim of this study was to describe the early effect of NTBC on renal tubular disease in patients with HT1. Methods Five HT1 patients (age between 5–53 months ) with different type of presentation were evaluated before and during the first 2 weeks of therapy with NTBC in a retrospective case analysis for phosphate metabolism and renal tubular function. Results Before starting NTBC therapy, all children manifested signs of renal dysfunction which included hypophosphatemia, acidosis, reduced phosphate reabsorption, aminoaciduria, glycosuria (Fanconi syndrome), and variable degree of proteinuria. Some patients also presented increased urinary calcium/creatinine ratio and raised fractional excretion of sodium. Starting of NTBC therapy resulted in the rapid normalization of plasma phosphate within one week from its initiation in majority of patients and in all patients during the second week of therapy. TmP/GFR normalized in 48 hours, while the other markers of renal dysfunction showed an improving trend over 2 weeks. Conclusions NTBC is an efficient treatment for renal tubular dysfunction in HT1, allowing the return to normal function within a few weeks. Its early effect on renal tubular cells appeared to be very rapid, particularly in normalizing plasma phosphate and TmP/GFR. In our series of patients, the TmP/GFR resulted as the most reliable index of tubular function.
    Molecular Genetics and Metabolism 11/2014; DOI:10.1016/j.ymgme.2014.07.021
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background In severe neonatal hyperammonemia, extracorporeal dialysis (ECD) provides higher ammonium clearance than peritoneal dialysis (PD). However, there are limited outcome data in relation to dialysis modality. Methods Data from infants with hyperammonemia secondary to inborn errors of metabolism (IEM) treated with dialysis were collected in six Italian centers and retrospectively analyzed. Results Forty-five neonates born between 1990 and 2011 were enrolled in the study. Of these, 23 were treated with PD and 22 with ECD (14 with continuous venovenous hemodialysis [CVVHD], 5 with continuous arteriovenous hemodialysis [CAVHD], 3 with hemodialysis [HD]). Patients treated with PD experienced a shorter duration of predialysis coma, while those treated with HD had a shorter ammonium decay time compared with all the other patients (p p = 0.016). Predialysis ammonium levels were significantly associated with a composite end-point of death or neurological sequelae (adjusted OR: 1.13 [1.02–1.27] per 100 μmol/l, p = 0.026). No association was found between outcome and dialysis modality. Conclusions In this study, a delayed ECD treatment was not superior to PD in improving the short-term outcome of neonates with hyperammonemia secondary to IEM.
    Pediatric Nephrology 09/2014; 30(5). DOI:10.1007/s00467-014-2945-x
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Cystinosis is caused by mutations in the CTNS gene (17p13.2), which encodes for a lysosomal cystine/proton symporter termed cystinosin. It is the most common cause of inherited renal Fanconi syndrome in young children. Because of its rarity, the diagnosis and specific treatment of cystinosis are frequently delayed, which has a significant impact on the overall prognosis. In this document, we have summarized expert opinions on several aspects of the disease to improve knowledge and provide guidance for diagnosis and treatment.
    Nephrology Dialysis Transplantation 09/2014; 29(suppl 4):iv87-iv94. DOI:10.1093/ndt/gfu090
  • Pediatric Nephrology 09/2014; 29(9):174.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Immunosuppressive and anti-inflammatory properties of bone marrow (BM)-derived mesenchymal stromal cells (MSCs) represent a promising tool in immunoregulatory and regenerative cell therapy. Clarifying the interactions between MSCs and B-lymphocytes may be crucial for designing innovative MSC-based strategies in conditions in which B cells play a role such as Systemic Lupus Erythematosus (SLE) and rejection of kidney transplantation. Here, we show that, both in healthy subjects and in patients, in vitro B-cell proliferation, plasma-cell differentiation and antibody production are inhibited by BM-derived MSCs when peripheral blood lymphocytes are stimulated with CpG, but not when sorted B cells are cultured with MSCs+CpG. Inhibition is restored in CpG+MSC co-cultures when sorted T cells are added to sorted B cells, suggesting that this effect is mediated by T cells, with both CD4+ and CD8+ playing a role. Moreover, cell-cell contact between MSCs and T cells, but not between MSCs and B cells, is necessary to inhibit B-cell proliferation. In conclusion, the presence of functional T cells, as well as cell-cell contact between MSCs and T cells are crucial for B cell inhibition. This information can be relevant for the use of MSC-based therapeutic immune-modulation in patients in whom T-cell function is impaired.
    Stem Cells and Development 07/2014; 36(4). DOI:10.1089/scd.2014.0155
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objective Refeeding syndrome can occur in several contexts of relative malnutrition in which an overaggressive nutritional support is started. The consequences are life-threatening with multiorgan impairment, and severe electrolyte imbalances. During refeeding, glucose-involved insulin secretion causes abrupt reverse of lipolysis and a switch from catabolism to anabolism. This creates a sudden cellular demand of electrolytes (phosphate, potassium and magnesium) necessary for ATP synthesis, glucose transport and other synthesis reactions, resulting in decreased serum levels. Laboratory findings and multiorgan impairment similar to refeeding syndrome are also observed in acute thiamine deficiency. Methods We describe two patients with leukemia who developed acute thiamine deficiency with an electrolyte pattern suggestive of refeeding syndrome, severe lactic acidosis and evidence of proximal renal tubular dysfunction. Results A single thiamine administration led to rapid resolution of the tubular dysfunction and normalization of acidosis and electrolytes imbalance. This demonstrated that thiamine deficiency was responsible for the electrolyte imbalance, caused by tubular electrolytes losses. Conclusions Our report indicates that, despite sharing many laboratory similarities, refeeding syndrome and acute thiamine deficiency should be viewed as separate entities in which the electrolyte abnormalities reported in cases of refeeding syndrome with thiamine deficiency and refractory lactic acidosis may be due to a renal tubular losses instead of a shifting from extracellular to intracellular compartment. In oncologic and malnourished patients, categories at particular risk of developing refeeding syndrome, in presence of these biochemical abnormalities, acute thiamine deficiency should be suspected and treated, because it promptly responds to thiamine administration.
    Nutrition 07/2014; 30(7-8). DOI:10.1016/j.nut.2014.02.019
  • Marina Vivarelli, Francesco Emma
    [Show abstract] [Hide abstract]
    ABSTRACT: C3 glomerulopathy (C3G) is a newly defined clinical entity comprising glomerular lesions with predominant C3 staining. Under this definition are now included membranoproliferative glomerulonephritis type II (dense deposit disease) and C3 glomerulonephritis. This group of glomerular diseases with a heterogeneous histological aspect shares a common pathogenesis, that is, a dysregulation of the alternative pathway of complement in the fluid phase leading to C3 deposition in the kidney. Recent advances have expanded our understanding of the underlying mechanisms, leading to the hypothesis that blocking the alternative complement pathway may be an effective treatment for C3Gs, as has been shown in other renal diseases driven by alternative pathway dysregulation, such as atypical hemolytic uremic syndrome. Results of 11 published cases of patients with different forms of C3G treated with eculizumab, an anti-C5 humanized monoclonal antibody, are encouraging. Given the complexity of disease pathogenesis in C3G, a patient-tailored approach including a comprehensive workup of complement abnormalities is necessary to evaluate the best treatment options. Clinical trials assessing effectiveness of different complement blockers on the background of the individual complement profile are needed.
    Seminars in Thrombosis and Hemostasis 05/2014; 40(4). DOI:10.1055/s-0034-1375299
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The Oxford Classification of IgA Nephropathy (IgAN) identified mesangial hypercellularity (M), endocapillary proliferation (E), segmental glomerulosclerosis (S), and tubular atrophy/interstitial fibrosis (T) as independent predictors of outcome. Whether it applies to individuals excluded from the original study and how therapy influences the predictive value of pathology remain uncertain. The VALIGA study examined 1147 patients from 13 European countries that encompassed the whole spectrum of IgAN. Over a median follow-up of 4.7 years, 86% received renin-angiotensin system blockade and 42% glucocorticoid/immunosuppressive drugs. M, S, and T lesions independently predicted the loss of estimated glomerular filtration rate (eGFR) and a lower renal survival. Their value was also assessed in patients not represented in the Oxford cohort. In individuals with eGFR less than 30 ml/min per 1.73 m(2), the M and T lesions independently predicted a poor survival. In those with proteinuria under 0.5 g/day, both M and E lesions were associated with a rise in proteinuria to 1 or 2 g/day or more. The addition of M, S, and T lesions to clinical variables significantly enhanced the ability to predict progression only in those who did not receive immunosuppression (net reclassification index 11.5%). The VALIGA study provides a validation of the Oxford classification in a large European cohort of IgAN patients across the whole spectrum of the disease. The independent predictive value of pathology MEST score is reduced by glucocorticoid/immunosuppressive therapy.Kidney International advance online publication, 2 April 2014; doi:10.1038/ki.2014.63.
    Kidney International 04/2014; DOI:10.1038/ki.2014.63
  • [Show abstract] [Hide abstract]
    ABSTRACT: The Oxford Classification of IgA Nephropathy (IgAN) identified mesangial hypercellularity (M), endocapillary proliferation (E), segmental glomerulosclerosis (S), and tubular atrophy/interstitial fibrosis (T) as independent predictors of outcome. Whether it applies to individuals excluded from the original study and how therapy influences the predictive value of pathology remain uncertain. The VALIGA study examined 1147 patients from 13 European countries that encompassed the whole spectrum of IgAN. Over a median follow-up of 4.7 years, 86% received renin–angiotensin system blockade and 42% glucocorticoid/immunosuppressive drugs. M, S, and T lesions independently predicted the loss of estimated glomerular filtration rate (eGFR) and a lower renal survival. Their value was also assessed in patients not represented in the Oxford cohort. In individuals with eGFR less than 30 ml/min per 1.73 m2, the M and T lesions independently predicted a poor survival. In those with proteinuria under 0.5 g/day, both M and E lesions were associated with a rise in proteinuria to 1 or 2 g/day or more. The addition of M, S, and T lesions to clinical variables significantly enhanced the ability to predict progression only in those who did not receive immunosuppression (net reclassification index 11.5%). The VALIGA study provides a validation of the Oxford classification in a large European cohort of IgAN patients across the whole spectrum of the disease. The independent predictive value of pathology MEST score is reduced by glucocorticoid/immunosuppressive therapy. Keywords: glomerular diseases; IgA nephropathy; progression of chronic renal failure; proteinuria; renal pathology; risk factors
  • Cytotherapy 04/2014; 16(4):S79. DOI:10.1016/j.jcyt.2014.01.290
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Intralysosomal cystine crystal accumulation, due to mutations in the CTNS gene, is a hallmark of nephropathic cystinosis, but the role of these crystals in disease pathogenesis remains unclear. We hypothesized that, similar to other host-derived crystalline moieties, cystine crystals can induce IL-1β production through inflammasome activation. Thus, we investigated the proinflammatory effects of cystine crystals in primary human PBMCs. LPS-primed PBMCs stimulated with cystine crystals secreted IL-1β in a dose-dependent manner. Similarly to IL-1β secretion induced by other crystalline inflammasome activators, cystine crystal-induced IL-1β secretion required activation of caspase-1. Additionally, exogenous cystine crystals were internalized by monocytes, and inhibition of phagocytosis, cathepsin B leakage, generation of reactive oxygen species, and potassium efflux reduced cystine crystal-induced IL-1β secretion. Patients with cystinosis had higher levels of circulating IL-1β and IL-18 compared with controls. Analysis of inflammasome-related gene expression in PBMCs from patients with cystinosis revealed a significant increase in IL-1β and CASP-1 transcript levels compared with controls. Moreover, knockout of cystinosin in mice led to significant increases in serum IL-18 levels and kidney expression of inflammasome-related genes (Casp-1, Pycard, Il-18, Il18r1, Il1r1, and Il1rl2). Taken together, these data demonstrate that cystine crystals are endogenous inflammasome-activating stimuli, suggesting a novel role for cystine crystals in the pathogenesis of nephropathic cystinosis.
    Journal of the American Society of Nephrology 02/2014; 25(6). DOI:10.1681/ASN.2013060653
  • Source
    Journal of the American Society of Nephrology 01/2014;
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The outcome of steroid-dependent or frequently relapsing nephrotic syndrome of minimal change disease (MCD), mesangial proliferative GN (MesGN), or FSGS may be poor and with major treatment toxicity. This academic, multicenter, off-on trial (ClinicalTrials.gov #NCT00981838) primarily evaluated the effects of rituximab therapy followed by immunosuppression withdrawal on disease recurrence in 10 children and 20 adults with MCD/MesGN (n=22) or FSGS who had suffered ≥2 recurrences over the previous year and were in steroid-induced remission for ≥1 month. Participants received one dose (n=28) or two doses of rituximab (375 mg/m(2) intravenously). At 1 year, all patients were in remission: 18 were treatment-free and 15 never relapsed. Compared with the year before rituximab treatment, total relapses decreased from 88 to 22 and the per-patient median number of relapses decreased from 2.5 (interquartile range [IQR], 2-4) to 0.5 (IQR, 0-1; P<0.001) during 1 year of follow-up. Reduction was significant across subgroups (children, adults, MCD/MesGN, and FSGS; P<0.01). After rituximab, the per-patient steroid maintenance median dose decreased from 0.27 mg/kg (IQR, 0.19-0.60) to 0 mg/kg (IQR, 0-0.23) (P<0.001), and the median cumulative dose to achieve relapse remission decreased from 19.5 mg/kg (IQR, 13.0-29.2) to 0.5 mg/kg (IQR, 0-9.4) (P<0.001). Furthermore, the mean estimated GFR increased from 111.3±25.7 to 121.8±29.2 ml/min per 1.73 m(2) (P=0.01), with the largest increases in children and in FSGS subgroups. The mean height z score slope stabilized in children (P<0.01). Treatment was well tolerated. Rituximab effectively and safely prevented recurrences and reduced the need for immunosuppression in steroid-dependent or frequently relapsing nephrotic syndrome, and halted disease-associated growth deficit in children.
    Journal of the American Society of Nephrology 01/2014; 25(4). DOI:10.1681/ASN.2013030251
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: WT1 mutations cause a wide spectrum of renal and extrarenal manifestations. Here we evaluated disease prevalence, phenotype spectrum, and genotype-phenotype correlations of 61 patients with WT1-related steroid-resistant nephrotic syndrome relative to 700 WT1-negative patients, all with steroid-resistant nephrotic syndrome. WT1 patients more frequently presented with chronic kidney disease and hypertension at diagnosis and exhibited more rapid disease progression. Focal segmental glomerulosclerosis was equally prevalent in both cohorts, but diffuse mesangial sclerosis was largely specific for WT1 disease and was present in 34% of cases. Sex reversal and/or urogenital abnormalities (52%), Wilms tumor (38%), and gonadoblastoma (5%) were almost exclusive to WT1 disease. Missense substitutions affecting DNA-binding residues were associated with diffuse mesangial sclerosis (74%), early steroid-resistant nephrotic syndrome onset, and rapid progression to ESRD. Truncating mutations conferred the highest Wilms tumor risk (78%) but typically late-onset steroid-resistant nephrotic syndrome. Intronic (KTS) mutations were most likely to present as isolated steroid-resistant nephrotic syndrome (37%) with a median onset at an age of 4.5 years, focal segmental glomerulosclerosis on biopsy, and slow progression (median ESRD age 13.6 years). Thus, there is a wide range of expressivity, solid genotype-phenotype associations, and a high risk and significance of extrarenal complications in WT1-associated nephropathy. We suggest that all children with steroid-resistant nephrotic syndrome undergo WT1 gene screening.Kidney International advance online publication, 8 January 2014; doi:10.1038/ki.2013.519.
    Kidney International 01/2014; 85(5). DOI:10.1038/ki.2013.519

Publication Stats

2k Citations
596.73 Total Impact Points

Institutions

  • 2001–2015
    • Ospedale Pediatrico Bambino Gesù
      • • Unit Pathology
      • • Department of Pediatric Cardiology and Cardiac Surgery
      • • Division of Neurology
      Roma, Latium, Italy
  • 2010
    • Università degli Studi di Torino
      Torino, Piedmont, Italy
  • 2009
    • University Health Network
      Toronto, Ontario, Canada
    • Oxford University Hospitals NHS Trust
      • Department of Cellular Pathology
      Oxford, ENG, United Kingdom
  • 2003–2007
    • Sapienza University of Rome
      • Department of Experimental Medicine
      Roma, Latium, Italy
  • 1998
    • Boston Children's Hospital
      Boston, Massachusetts, United States
  • 1994–1998
    • Harvard Medical School
      • • Department of Anesthesia
      • • Department of Medicine
      Boston, Massachusetts, United States