Steroid-Resistant Nephrotic Syndrome Is Associated With a Unique Genetic Profile in a Highly Admixed Pediatric Population.

Introduction: The profile of genetic and nongenetic factors associated with progression to kidney failure (KF) in steroid-resistant nephrotic syndrome (SRNS) is largely unknown in admixed populations.

Methods: A total of 101 pediatric patients with primary SRNS were genetically assessed targeting Mendelian causes and status with a 62-NS-gene panel or whole exome sequencing, as well as genetic ancestry. Variant pathogenicity was evaluated using the American College Medical of Genetics and Genomics (ACMG) criteria.

Real-world data of Brazilian adults with X-linked hypophosphatemia (XLH) treated with burosumab and comparison with other worldwide cohorts.

Background: Disease-related variants in PHEX cause XLH by an increase of fibroblast growth factor 23 (FGF23) circulating levels, resulting in hypophosphatemia and 1,25(OH) vitamin D deficiency. XLH manifests in early life with rickets and persists in adulthood with osseous and extraosseous manifestations. Conventional therapy (oral phosphate and calcitriol) improves some symptoms, but evidence show that it is not completely effective, and it can lead to nephrocalcinosis (NC) and hyperparathyroidism (HPT).

A comprehensive model for assessing and classifying patients with thrombotic microangiopathy: the TMA-INSIGHT score.

Background: Thrombotic Microangiopathy (TMA) is a syndrome characterized by the presence of anemia, thrombocytopenia and organ damage and has multiple etiologies. The primary aim is to develop an algorithm to classify TMA (TMA-INSIGHT score).

Methods: This was a single-center retrospective cohort study including hospitalized patients with TMA at a single center.

Bartter Syndrome-Related Variants Distribution: Brazilian Data and Its Comparison with Worldwide Cohorts.

Background: Genetic testing is recommended for accurate diagnosis of Bartter syndrome (BS) and serves as a basis for implementing specific target therapies. However, populations other than Europeans and North Americans are underrepresented in most databases and there are uncertainties in the genotype-phenotype correlation. We studied Brazilian BS patients, an admixed population with diverse ancestry.

Baseline characteristics and evolution of Brazilian patients with atypical hemolytic uremic syndrome: first report of the Brazilian aHUS Registry.

Background: Atypical hemolytic uremic syndrome (aHUS) is an ultra-rare disease. Therefore, studies involving large samples are scarce, making registries powerful tools to evaluate cases. We present herein the first analysis of the Brazilian aHUS Registry (BRaHUS).

Recommendations for the diagnosis and management of Fabry disease in pediatric patients: a document from the Rare Diseases Committee of the Brazilian Society of Nephrology (Comdora-SBN).

Fabry disease (FD) is a genetic disease, with X-chromosome linked inheritance, due to variants in the GLA gene that encodes the α-galactosidase A (α-GAL) enzyme. The purpose of the present study was to create a consensus aiming to standardize the recommendations regarding the renal involvement of FD with guidelines on the diagnosis, screening, and treatment of pediatric patients. This consensus is an initiative of the Rare Diseases Committee (Comdora) of the Brazilian Society of Nephrology (SBN).

Brazilian consensus recommendations for the diagnosis, screening, and treatment of individuals with fabry disease: Committee for Rare Diseases - Brazilian Society of Nephrology/2021.

Fabry disease (FD) is an X-linked inherited disorder caused by mutations in the GLA gene encoding enzyme alpha-galactosidase A (α-Gal A). The purpose of this study was to produce a consensus statement to standardize the recommendations concerning kidney involvement in FD and provide advice on the diagnosis, screening, and treatment of adult and pediatric patients. This consensus document was organized from an initiative led by the Committee for Rare Diseases (Comdora) of the Brazilian Society of Nephrology (SBN).

Distal Renal Tubular Acidosis Associated with Autoimmune Diseases: Reports of 3 Cases and Review of Mechanisms.

BACKGROUND Distal renal tubular acidosis (dRTA) is a defect in the urinary acidification process that limits the elimination of protons [H+] by alpha intercalated cells in the collecting tubules, with consequent metabolic acidosis with a normal plasma anion gap. The relationship between this tubulopathy and immune-mediated diseases like Sjögren syndrome, rheumatoid arthritis, autoimmune hepatitis, primary biliary cirrhosis, systemic lupus erythematosus, and thyroiditis is well known. Further, the pathophysiological mechanisms are diverse, but, unfortunately, many are not yet fully understood.

Cysteamine bitartrate delayed-release capsules control leukocyte cystine levels and promote statural growth and kidney health in an open-label study of treatment-naïve patients <6 years of age with nephropathic cystinosis.

Nephropathic cystinosis is a rare autosomal recessive lysosomal storage disease that is characterized by accumulation of cysteine and formation of crystals within cells of different organs and tissues causing systemic manifestations in childhood that include poor linear growth, ocular involvement, hypothyroidism, and progressive kidney disease. This study was a long-term, prospective open-label evaluation of twice-daily delayed release (DR) cysteamine capsules in cystinosis patients <6 years of age who were naïve to any form of cysteamine treatment. Fifteen treatment-naïve patients <6 years old (mean age 2.

Eculizumab interruption in atypical hemolytic uremic syndrome due to shortage: analysis of a Brazilian cohort.

Background: The risk of eculizumab therapy discontinuation in patients with atypical hemolytic uremic syndrome (aHUS) is unclear. The main objective of this study was to analyze the risk of aHUS relapse after eculizumab interruption due to drug shortage in Brazil.

Methods: We screened all the registered dialysis centers in Brazil (n = 800), willing to participate in the aHUS Brazilian shortage cohort, through electronic mail and formal invitation by the Brazilian Society of Nephrology.

COMDORA-SBN recommendations for patients with rare kidney diseases in relation to the Covid-19 pandemic.

During the Covid-19 pandemic, the issue is how to maintain adequate care for people with other diseases. In this document, the SBN Rare Diseases Committee (COMDORA) gives some guidelines on the care of patients with rare kidney diseases. These patients should follow the recommendations for the general population, bearing in mind that, as they have chronic kidney disease, they are included in the risk group for more serious outcomes if they develop Covid-19.

Multidisciplinary approach for patients with nephropathic cystinosis: model for care in a rare and chronic renal disease.

Care for patients with chronic and rare diseases is complex, especially considering the lack of knowledge about the disease, which makes early and precise diagnosis difficult, as well as the need for specific tests, sometimes of high complexity and cost. Added to these factors are difficulties in obtaining adequate treatment when available, in raising patient and family awareness about the disease and treatment compliance. Nephropathic cystinosis is among these diseases.

Thrombotic microangiopathy caused by methionine synthase deficiency: diagnosis and treatment pitfalls.

Background: Inborn errors of cobalamin (Cbl) metabolism form a large group of rare diseases. One of these, Cbl deficiency type C (CblC), is a well-known cause of thrombotic microangiopathy (TMA), especially in infants. However, there has only been a single published case of TMA associated to Cbl deficiency type G (CblG), also known as methionine synthase deficiency (MSD).

[Nephrotic syndrome as the first manifestation of juvenile systemic scleroderma.].

Renal involvement occurs in 1%-12% in juvenile systemic sclerosis (JSSc) patients, mainly with arterial hypertension, proteinuria and scleroderma renal crisis. We report herein a patient who presented nephrotic syndrome (NS) as the first manifestation of JSSc with focal segmental glomerulosclerosis (FSGS). A female patient presented steroid-sensitive NS at the age of 12 years.

Hemolytic-Uremic Syndrome in childhood.

There is a group of diseases that may manifest with thrombotic microangiopathy and present clinical overlap. Among these we emphasize the thrombotic thrombocytopenic purpura and Hemolytic Uremic Syndrome, and the latter can occur by the action of toxins, systemic diseases, overactivation of the alternative complement system pathway, which can occur due to changes in regulatory proteins (atypical HUS) and finally, idiopathic. You must carry out a series of tests to differentiate them.

Treatment of Bartter syndrome. Unsolved issue.

Objective: To describe the results of a long-term follow-up of Bartter syndrome patients treated with different drugs.

Method: Patients were diagnosed according to clinical and laboratory data. Treatment protocol was potassium supplementation, sodium, spironolactone, and non-steroidal anti-inflammatory drug.

N-acetyl-cysteine is associated to renal function improvement in patients with nephropathic cystinosis.

Background: Nephropathic cystinosis is an autosomal recessive systemic severe disease characterized by intralysosomal cystine storage. Cysteamine is an essential component of treatment. There is solid evidence that cystine accumulation itself is not responsible for all abnormalities in cystinosis; there is also a deficiency of glutathione in the cytosol.

[Eculizumab for the treatment of atypical hemolytic uremic syndrome: case report and revision of the literature].

SHU atypical (aHUS), that is, not associated with Escherichia coli Shiga toxinproducing, is seen in 5 to 10% of cases of Hemolytic Uremic Syndrome (HUS), and can occur at any age and may be sporadic or familial. The prognosis in these cases is reserved, with high mortality and morbidity in the acute phase of the disease, and about 50% of cases can develop chronic kidney disease. The increased knowledge of the pathogenesis of aHUS (overactivation of the alternative pathway of complement), was accompanied by the appearance of a drug, eculizumab, which acts as an inhibitor of membrane attack complex.

[Practical markers of renal function in cystinosis patients].

Background: Cystinosis is an autossomic recessive systemic disease that leads to renal insufficiency early in life unless cysteamine be started early. Unfortunately, even in this situation the patients will develop chronic renal disease with need of renal replacement therapy about second decade of life. Therefore, the renal function evaluation is essential to these patients.

Pharmacokinetics of cyclosporin--a microemulsion in children with idiopathic nephrotic syndrome.

Objective: We present a prospective study of a microemulsion of cyclosporin to treat idiopathic nephrotic syndrome in ten children with normal renal function who presented cyclosporin trough levels between 50 and 150 ng/ml and achieved complete remission with cyclosporin. To compare the pharmacokinetic parameters of cyclosporin in idiopathic nephrotic syndrome during remission and relapse of the nephrotic state.

Method: The pharmacokinetic profile of cyclosporin was evaluated with the 12-hour area under the time-concentration curve (auc0-12) using seven time-point samples.

The long-term use of enalapril and hydrochlorothiazide in two novel mutations patients with Dent's disease type 1.

Dent's disease type 1 is an X-linked tubular disease caused by mutations in the renal chloride channel CLCN-5, and it is characterized by low molecular weight proteinuria, hypercalciuria, nephrocalcinosis, and renal failure. Several cases have been described in which the only presenting symptoms were asymptomatic proteinuria, and focal segmental or global glomerulosclerosis. The renal failure in these patients may be caused by hypercalciuria and persistent proteinuria.