Multidimensional inflammatory and immunological endotypes of idiopathic focal segmental glomerulosclerosis and their association with treatment outcomes

Endotips; Glomerulosclerosi segmentària focal; Resposta inflamatòriaEndotipos; Glomeruloesclerosis segmentaria focal; Respuesta inflamatoriaEndotypes; Focal segmental glomerulosclerosis; Inflammatory responseObjectives Idiopathic focal segmental glomerulosclerosis (FSGS) has been linked to immunological and inflammatory response dysregulations. The aim of this study was to find endotypes of FSGS patients using a cluster (CL) analysis based on inflammatory and immunological variables, and to analyse whether a certain endotype is associated with response to treatment with corticosteroids. Methods This prospective observational study included patients with idiopathic FSGS diagnosed by kidney biopsy. Serum levels of soluble interleukin (IL)-1 receptor, tumoural necrosis factor alpha, Interferon gamma (IFNγ), IL-6, IL-17, IL-12, IL-23, IL-13, IL-4, IL-5, IL-6, haemopexin (Hx), haptoglobin (Hgl), soluble urokinase-type plasminogen activator receptor (suPAR) and urinary CD80 (uCD80) were measured with enzyme-linked immunosorbent assay or nephelometry. T-helper lymphocyte populations and T-regulatory lymphocytes were analysed by flow cytometry. A factorial analysis followed by a k-means CL analysis was performed. Results A total of 79 FSGS patients were included. Three CLs were identified. CL1 (27.8%) included IL-12, IL-17, IL-23 and a T helper 17 (Th17) pattern. CL2 (20.2%) included IL-4, IL-5, IL-13, immunoglobulin E and Th2 pattern. CL3 (51.8%) included IL-6, Hx, Hgl, suPAR and uCD80. There were no differences in age, gender, kidney function, albumin or proteinuria among CLs. About 42/79 patients (53.1%) showed cortico-resistance. The prevalence of cortico-resistance was significantly lower in CL2 (4/16, 25%) than in CL1 (16/26, 72.7%) and CL3 (22/41, 53.7%) (P = 0.018), with no significant differences between CLs 1 and 3 (P = 0.14). Conclusions Patients with FSGS and indistinguishable clinical presentation at diagnosis were classified in three distinct CLs according to predominant Th17, Th2 and acute inflammatory responses that display differences in clinical response to treatment with corticosteroids

ePHex: a phase 3, double-blind, placebo-controlled, randomized study to evaluate long-term efficacy and safety of Oxalobacter formigenes in patients with primary hyperoxaluria

Oxabact; Oxalobacter formigenes; Primary hyperoxaluriaOxabact; Oxalobacter formigenes; Hiperoxaluria primariaOxabact; Oxalobacter formigenes; Hiperoxalúria primàriaBackground Primary hyperoxalurias (PHs) are rare genetic diseases that increase the endogenous level of oxalate, a waste metabolite excreted predominantly by the kidneys and also the gut. Treatments aim to improve oxalate excretion, or reduce oxalate generation, to prevent kidney function deterioration. Oxalobacter formigenes is an oxalate metabolizing bacterium. This Phase III, double-blind, placebo-controlled randomized trial investigated the effectiveness of orally administered Oxabact™, a lyophilized O. formigenes formulation, at reducing plasma oxalate levels in patients suffering from PH. Methods Subjects (≥ 2 years of age) with a diagnosis of PH and maintained but suboptimal kidney function (mean estimated glomerular filtration rate at baseline < 90 mL/min/1.73 m2) were eligible to participate. Subjects were randomized to receive Oxabact or placebo twice daily for 52 weeks. Change from baseline in plasma oxalate concentration at Week 52 was the primary study endpoint. Results Forty-three subjects were screened, 25 were recruited and one was discontinued. At Week 52, O. formigenes was established in the gut of subjects receiving Oxabact. Despite decreasing plasma oxalate level in subjects treated with Oxabact, and stable/increased levels with placebo, there was no significant difference between groups in the primary outcome (Least Squares mean estimate of treatment difference was − 3.80 μmol/L; 95% CI: − 7.83, 0.23; p-value = 0.064). Kidney function remained stable in both treatments. Conclusions Oxabact treatment may have stabilized/reduced plasma oxalate versus a rise with placebo, but the difference over 12 months was not statistically significant (p = 0.06). A subtle effect observed with Oxabact suggests that O. formigenes may aid in preventing kidney stones.The study was designed, funded, and managed by OxThera Intellectual Property AB (Stockholm, Sweden)

CD44-negative parietal–epithelial cell staining in minimal change disease: association with clinical features, response to corticosteroids and kidney outcome

Idiopathic nephrotic syndrome; Minimal change disease; Parietal–epithelial cellsSíndrome nefrótico idiopático; Enfermedad de cambios mínimos; Células parietales-epitelialesSíndrome nefròtica idiopàtica; Malaltia de canvis mínims; Cèl·lules parietals-epitelialsBackground Activation of parietal–epithelial cells (PECs) with neo-expression of CD44 has been found to play a relevant role in the development of focal and segmental glomerulosclerosis (FSGS). The aim of this study was to analyse whether the expression of CD44 by PECs in biopsies of minimal change disease (MCD) is associated with the response to corticosteroids, with kidney outcomes and/or can be considered an early sign of FSGS. Methods This multicentric, retrospective study included paediatric and adult patients with MCD. Demographic, clinical and biochemical data were recorded, and biopsies were stained with anti-CD44 antibodies. The association between PECs, CD44 expression and the response to corticosteroids, and kidney outcomes were analysed using logistic, Kaplan–Meier and Cox regression analyses. Results A total of 54 patients were included: 35 (65%) <18 years and 19 (35%) adults. Mean follow-up was 68.3 ± 37.9 months. A total of 19/54 patients (35.2%) showed CD44-positive staining. CD44-positive patients were younger (14.5 ± 5 versus 21.5 ± 13, P = 0.006), and showed a higher incidence of steroid-resistance [11/19 (57.8%) versus 7/35 (20%), P = 0.021; odds ratio: 5.5 (95% confidence interval 1.6–18), P = 0.007] and chronic kidney disease [9/19 (47.3%) versus 6/35 (17.1%), P = 0.021; relative risk: 3.01 (95% confidence interval 1.07–8.5), P = 0.037]. Follow-up re-biopsies of native kidneys (n = 18), identified FSGS lesions in 10/12 (83.3%) of first-biopsy CD44-positive patients versus 1/6 (16.7%) of first-biopsy CD44-negative patients (P = 0.026). Conclusions In patients with a light microscopy pattern of MCD, CD44-positive staining of PECs is associated with a higher prevalence of steroid resistance and worse kidney outcomes, and can be considered an early sign of FSGS.C.M. is supported by a Miguel Servet grant, Fondo de investigación sanitaria, Instituto de Salud Carlos III, Ministerio de Ciencia, Innovacio´n y Universidades [CP18/00116]. No additional funding was required for the current study

Nefrotoxicidad glomerular tardía en niños con leucemia aguda linfoblástica

Introducción En el tratamiento de la leucemia aguda linfoblástica (LAL) infantil se utilizan habitualmente altas dosis de methotrexate (MTX), entre otros quimioterápicos. Este tratamiento puede ocasionar un deterioro transitorio de la función renal que es bien conocido, si bien los posibles cambios a largo plazo no están muy descritos. El objetivo general de este estudio es evaluar la posible toxicidad glomerular tardía de dos protocolos de tratamiento de LAL de la Sociedad Española de Hematología y Oncología Pediátrica (SHOP-99 y SHOP-2005), teniendo en cuenta el incremento de dosis de MTX en el protocolo SHOP-2005 con respecto al SHOP-99. Además, nos planteamos como objetivos específicos, el establecer una nueva ecuación de estimación del filtrado glomerular (FG) basada en procedimientos de creatinina estandarizada, acorde con los procedimientos actuales de medida de nuestro laboratorio, y comparar dicha ecuación con la actualmente recomendada de Schwartz 2009. Material y métodos Evaluamos la función renal glomerular en 45 niños afectos de LAL. Hemos analizado la creatinina sérica y filtrado glomerular estimado (FGe) en el momento del diagnóstico de la enfermedad, al final del tratamiento y en el seguimiento. En este último control determinamos también la cistatina C sérica y la albuminuria. Para determinar el FGe utilizamos la ecuación de Schwartz original o la ecuación de Schwartz actualizada, dependiendo del momento en el cual se efectúa el control, acorde con el procedimiento de medida del laboratorio en el momento de la determinación. Clasificamos el FGe y la albuminuria según las categorías KDIGO (Kidney Disease Improving Global Outcomes) Para generar una nueva ecuación de estimación del FG, se efectúa una comparación de métodos de medida de creatinina entre el procedimiento de Jaffe cinético y el enzimático en 337 muestras de sangre de controles, obteniendo dicha ecuación a través de una recta de regresión. Resultados Un 20% de los pacientes tienen un FGe disminuido en el momento del diagnóstico. En el último control, 10 pacientes (22,2%) presentan una disminución leve del FGe (categoría G2 de la clasificación KDIGO). No hay diferencias estadísticamente significativas en la variable FG según KDIGO entre los protocolos SHOP-99 y el SHOP-2005 en ninguno de los tres controles. Las medias de la cistatina C en ambos protocolos se sitúan dentro de los valores normales y son muy similares. Tres pacientes (6,6%) presentan albuminuria elevada en el último seguimiento (categoría A2 de la clasificación KDIGO). A través de una recta de regresión generamos una nueva ecuación de estimación del FG basada en la creatinina (llamada HSP-09) que evita una sobreestimación del FG de 6,8% cuando se compara con la ecuación Schwartz 2009. Conclusiones Nuestros resultados muestran una afectación renal en el debut de la enfermedad. En el último seguimiento se constata una leve disminución del FGe o albuminuria elevada en el 28,8% de los pacientes, sin diferencias significativas entre ambos protocolos. Es necesario un seguimiento a largo plazo de estos pacientes.Introduction High-dose methotrexate (HD-MTX) is commonly used, among other chemotherapeutic agents, in the treatment of acute lymphoblastic leukemia (ALL) in children. This treatment may cause a transient deterioration of kidney function that is well known, even though the possible long-term changes are not well described. The overall objective of this study is to assess the potential of late glomerular toxicity of two treatment protocols of the Spanish Society of Pediatric Hematology and Oncology (SHOP-99 and SHOP-2005) for ALL, taking into account the increase in dose of MTX in the SHOP-2005 protocol with respect to SHOP-99. In addition, we set as specific objectives, to establish a new equation to estimate the glomerular filtration rate (GFR) based on standardized procedures of creatinine measurement, in line with current measuring procedures used in our laboratory, and to compare it with the currently recommended Schwartz 2009 equation. Material and methods We evaluate the renal glomerular function in 45 children with ALL. We have analyzed the serum creatinine and estimated glomerular filtration (eGFR) at the time of diagnosis of the disease, at the end of the treatment and during follow up. In the latter we also monitored the serum cystatin C and urinary albumin excretion. To determine the eGFR we use the original Schwartz equation or updated Schwartz equation, depending on the time in which the control is carried out, in accordance with the laboratory procedure for creatinine measurement at the time of the determination. We classify the eGFR and urinary albumin excretion according the KDIGO categories (Kidney Disease Improving Global Outcomes). In order to generate a new equation for estimating the GFR, a comparison of measurement methods of creatinine is done between the kinetic Jaffe and the enzyme methods in 337 blood samples from controls, resulting in a new equation established through a regression line. Results Twenty per cent of the patients have a decline in eGFR at the time of diagnosis. In the last control, 10 patients (22.2 %) showed a slight decrease of the eGFR (category G2 KDIGO classification). There are no statistically significant differences between SHOP-99 and SHOP-2005 protocols in eGFR according to KDIGO, in none of the three controls. Mean values of cystatin C in both protocols fall within the normal values and are very similar. Three patients (6.6 %) present elevated urinary albumin excretion in the last follow-up (category A2 of the KDIGO classification). We generate a creatinine-based new equation for estimating eGFR based on the creatinine (called HSP-09) that prevents an overestimation of the eGFR of 6.8 % when compared with the 2009 Schwartz equation. Conclusions Our results show renal function changes in the debut of the disease. In the last follow-up a slight decrease of the eGFR or elevated urinary albumin excretion is observed in 28.8 % of the patients, without significant differences between both protocols. A long-term follow-up of these patients is needed

Tenofovir vs lamivudine plus adefovir in chronic hepatitis B: TENOSIMP-B study

AIM To demonstrate the non-inferiority (15% non-inferiority limit) of monotherapy with tenofovir disoproxil fumarate (TDF) vs the combination of lamivudine (LAM) plus adefovir dipivoxil (ADV) in the maintenance of virologic response in patients with chronic hepatitis B (CHB) and prior failure with LAM. METHODS This study was a Phase IV prospective, randomized, open, controlled study with 2 parallel groups (TDF and LAM+ADV) of adult patients with hepatitis B e antigen (HBeAg)-negative CHB, prior failure with LAM, on treatment with LAM+ADV for at least 6 mo, without prior resistance to ADV and with an undetectable viral load at the start of the study, in 14 Spanish hospitals. The follow-up time for each patient was 48 wk after randomization, with quarterly visits in which the viral load, biochemical and serological parameters, adverse effects, adherence to treatment and consumption of hospital resources were analysed. RESULTS Forty-six patients were evaluated [median age: 55.4 years (30.2-75.2); 84.8% male], including 22 patients with TDF and 24 with LAM+ADV. During study development, hepatitis B virus DNA (HBV-DNA) remained undetectable, all patients remained HBeAg negative, and hepatitis B surface antigen (HBsAg) positive. Alanine aminotransferase (ALT) values at the end of the study were similar in the 2 groups (25.1 ± 7.65, TDF vs 24.22 ± 8.38, LAM+ADV, P = 0.646). No significant changes were observed in creatinine or serum phosphorus values in either group. No significant differences between the 2 groups were noted in the identification of adverse effects (AEs) (53.8%, TDF vs 37.5%, LAM+ADV, P = 0.170), and none of the AEs which occurred were serious. Treatment adherence was 95.5% and 83.3% in the TDF and the LAM+ADV groups, respectively (P = 0.488). The costs associated with hospital resource consumption were significantly lower with the TDF treatment than the LAM+ADV treatment (€4943 ± 1059 vs €5811 ± 1538, respectively, P < 0.001). CONCLUSION TDF monotherapy proved to be safe and not inferior to the LAM+ADV combination therapy in maintaining virologic response in patients with CHB and previous LAM failure. In addition, the use of TDF generated a significant savings in hospital costs

Nephrin mutations cause childhood- and adult-onset focal segmental glomerulosclerosis

Mutations in the NPHS1 gene cause congenital nephrotic syndrome of the Finnish type presenting before the first 3 months of life. Recently, NPHS1 mutations have also been identified in childhood-onset steroid-resistant nephrotic syndrome and milder courses of disease, but their role in adults with focal segmental glomerulosclerosis remains unknown. Here we developed an in silico scoring matrix to evaluate the pathogenicity of amino-acid substitutions using the biophysical and biochemical difference between wild-type and mutant amino acid, the evolutionary conservation of the amino-acid residue in orthologs, and defined domains, with the addition of contextual information. Mutation analysis was performed in 97 patients from 89 unrelated families, of which 52 presented with steroid-resistant nephrotic syndrome after 18 years of age. Compound heterozygous or homozygous NPHS1 mutations were identified in five familial and seven sporadic cases, including one patient 27 years old at onset of the disease. Substitutions were classified as ‘severe’ or ‘mild’ using this in silico approach. Our results suggest an earlier onset of the disease in patients with two ‘severe’ mutations compared to patients with at least one ‘mild’ mutation. The finding of mutations in a patient with adult-onset focal segmental glomerulosclerosis indicates that NPHS1 analysis could be considered in patients with later onset of the disease

Autosomal dominant polycystic kidney disease in young adults

Background The clinical manifestations of autosomal dominant polycystic kidney disease (ADPKD) usually appear in adulthood, however pediatric series report a high morbidity. The objective of the study was to analyze the clinical characteristics of ADPKD in young adults. Methods Family history, hypertension, albuminuria, estimated glomerular filtration rate (eGFR) and imaging tests were examined in 346 young adults (18-30 years old) out of 2521 patients in the Spanish ADPKD registry (REPQRAD). A literature review searched for reports on hypertension in series with more than 50 young (age <30 years) ADPKD patients. Results The mean age of this young adult cohort was 25.24 (SD 3.72) years. The mean age at diagnosis of hypertension was 21.15 (SD 4.62) years, while in the overall REPQRAD population was aged 37.6 years. The prevalence of hypertension was 28.03% and increased with age (18-24 years, 16.8%; 25-30 years, 36.8%). Although prevalence was lower in women than in men, the age at onset of hypertension (21 years) was similar in both sexes. Mean eGFR was 108 (SD 21) mL/min/1.73 m(2), 38.0% had liver cysts and 3.45% of those studied had intracranial aneurysms. In multivariate analyses, hematuria episodes and kidney length were independent predictors of hypertension (area under the curve 0.75). The prevalence of hypertension in 22 pediatric cohorts was 20%-40%, but no literature reports on hypertension in young ADPKD adults were found. Conclusions Young adults present non-negligible ADPKD-related morbidity. This supports the need for a thorough assessment of young adults at risk of ADPKD that allows early diagnosis and treatment of hypertension. Lay Summary Impairment of renal function usually develops from the fourth decade of life in autosomal dominant polycystic kidney disease (ADPKD). However, hypertension precedes the onset of renal insufficiency. In published pediatric series, the prevalence of hypertension is 20%-40%. However, clinical information on young adults with ADPKD is scarce. We present the largest cohort of young adults (age 18-30 years) with ADPKD published to date. Prevalence of hypertension is 28% and increases with age, reaching 36.8% in the subgroup aged 25-30 years, despite normal glomerular filtration rate and albuminuria. The prevalence of hypertension is higher in males, but the mean age at diagnosis (21 years) was similar in both sexes. Young adults present non-negligible ADPKD-related morbidity. This supports the need for a thorough assessment that allows early diagnosis and treatment of hypertension, before decline of estimated glomerular filtration rate. Ambulatory blood pressure monitoring may be especially useful in this regard.11 página

Targeted next-generation sequencing in steroid-resistant nephrotic syndrome : mutations in multiple glomerular genes may influence disease severity

Altres ajuts: Fundación Renal Iñigo Álvarez de Toledo (FRIAT)Genetic diagnosis of steroid-resistant nephrotic syndrome (SRNS) using Sanger sequencing is complicated by the high genetic heterogeneity and phenotypic variability of this disease. We aimed to improve the genetic diagnosis of SRNS by simultaneously sequencing 26 glomerular genes using massive parallel sequencing and to study whether mutations in multiple genes increase disease severity. High-throughput mutation analysis was performed in 50 SRNS and/or focal segmental glomerulosclerosis (FSGS) patients, a validation cohort of 25 patients with known pathogenic mutations, and a discovery cohort of 25 uncharacterized patients with probable genetic etiology. In the validation cohort, we identified the 42 previously known pathogenic mutations across NPHS1, NPHS2, WT1, TRPC6, and INF2 genes. In the discovery cohort, disease-causing mutations in SRNS/FSGS genes were found in nine patients. We detected three patients with mutations in an SRNS/FSGS gene and COL4A3. Two of them were familial cases and presented a more severe phenotype than family members with mutation in only one gene. In conclusion, our results show that massive parallel sequencing is feasible and robust for genetic diagnosis of SRNS/FSGS. Our results indicate that patients carrying mutations in an SRNS/FSGS gene and also in COL4A3 gene have increased disease severity

An RNAi in silico approach to find an optimal shRNA cocktail against HIV-1

<p>Abstract</p> <p>Background</p> <p>HIV-1 can be inhibited by RNA interference <it>in vitro </it>through the expression of short hairpin RNAs (shRNAs) that target conserved genome sequences. <it>In silico </it>shRNA design for HIV has lacked a detailed study of virus variability constituting a possible breaking point in a clinical setting. We designed shRNAs against HIV-1 considering the variability observed in naïve and drug-resistant isolates available at public databases.</p> <p>Methods</p> <p>A Bioperl-based algorithm was developed to automatically scan multiple sequence alignments of HIV, while evaluating the possibility of identifying dominant and subdominant viral variants that could be used as efficient silencing molecules. Student t-test and Bonferroni Dunn correction test were used to assess statistical significance of our findings.</p> <p>Results</p> <p>Our <it>in silico </it>approach identified the most common viral variants within highly conserved genome regions, with a calculated free energy of ≥ -6.6 kcal/mol. This is crucial for strand loading to RISC complex and for a predicted silencing efficiency score, which could be used in combination for achieving over 90% silencing. Resistant and naïve isolate variability revealed that the most frequent shRNA per region targets a maximum of 85% of viral sequences. Adding more divergent sequences maintained this percentage. Specific sequence features that have been found to be related with higher silencing efficiency were hardly accomplished in conserved regions, even when lower entropy values correlated with better scores. We identified a conserved region among most HIV-1 genomes, which meets as many sequence features for efficient silencing.</p> <p>Conclusions</p> <p>HIV-1 variability is an obstacle to achieving absolute silencing using shRNAs designed against a consensus sequence, mainly because there are many functional viral variants. Our shRNA cocktail could be truly effective at silencing dominant and subdominant naïve viral variants. Additionally, resistant isolates might be targeted under specific antiretroviral selective pressure, but in both cases these should be tested exhaustively prior to clinical use.</p