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. We included all consecutive patients diagnosed with TMA between 2012 and 2021. TMA was defined based on the presence of anemia (hemoglobin level < 10 g/dL) and thrombocytopenia (platelet count < 150,000/µL), signs of hemolysis, and organ damage. We classified patients in eight categories: infections; Malignant Hypertension; Transplant; Malignancy; Pregnancy; Thrombotic Thrombocytopenic Purpura (TTP); Shiga toxin-mediated hemolytic uremic syndrome (STEC-SHU) and Complement Mediated TMA (aHUS). We fitted a model to classify patients using clinical characteristics, biochemical exams, and mean arterial pressure at presentation. RESULTS: We retrospectively retrieved TMA phenotypes using automatic strategies in electronic health records in almost 10 years (n = 2407). Secondary TMA was found in 97.5% of the patients. Primary TMA was found in 2.47% of the patients (TTP and aHUS). The best model was LightGBM with accuracy of 0.979, and multiclass ROC-AUC of 0.966. The predictions had higher accuracy in most TMA classes, although the confidence was lower in aHUS and STEC-HUS cases. CONCLUSION: Secondary conditions were the most common etiologies of TMA. We retrieved comorbidities, associated conditions, and mean arterial pressure to fit a model to predict TMA and define TMA phenotypic characteristics. This is the first multiclass model to predict TMA including primary and secondary conditions.

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). CASE DIAGNOSIS/TREATMENT: A 21-month-old boy presented with pallor and oral ulcers during episodes of upper respiratory infection (URI). Further examination revealed signs of TMA, and the patient progressed to acute renal failure (ARF). Renal biopsy showed TMA. Evaluation for infection and autoantibodies were negative. The C3 and C4 complement fractions were normal. Analysis of the bone marrow aspirate suggested megaloblastic anemia and signs of hematopoiesis activation (secondary to peripheral hemolysis). Although the serum vitamin B12 level was normal, the patient was treated with cyanocobalamin, with no improvement. The ARF and hematologic parameters improved with conservative treatment. A severe relapse occurred during the follow-up, with normal ADAMTS13 activity. The presumed diagnosis was atypical hemolytic uremic syndrome, and the patient was started on eculizumab, but his response was poor, even when the dosage was increased. At this point it was also recognized that his developmental speech was delayed. Based on these findings, whole exome sequencing was performed, leading to the detection of two novel deleterious variants in the gene coding for methionine synthase, confirming the diagnosis of MSD. Subsequent treatment consisted of elevating the patient's serum homocysteine level and starting him on hydroxicobalamin, with normalization of all hematologic parameters although the microalbuminuria remained. CONCLUSIONS: Methionine synthase deficiency is very rare and characterized by megaloblastic anemia and neurological symptoms. We report the second case of MSD associated to TMA previously diagnosed as aHUS in which the patient had a poor response to eculizumab.

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. Patients with cystinosis can be more susceptible to oxidative stress. CASE-DIAGNOSIS/TREATMENT: The patient cohort comprised 23 cystinosis patients (16 males) aged <18 years (mean age 8.0 ± 3.6 years) with chronic kidney disease class I-IV with good adherence to treatment, including cysteamine. Oxidative stress was evaluated based on the levels of serum thiobarbituric acid-reactive substances (TBARS), and renal function was evaluated based on serum creatinine and cystatin C levels and creatinine clearance (Schwartz formula). N-Acetylcysteine (NAC), an antioxidant drug was given to all patients for 3 months (T1) at 25 mg/kg/day divided in three doses per day. The measured values at just before the initiation of NAC treatment (T0) served as the control for each patient. RESULTS: Median serum TBARS levels at T0 and T1 were 6.92 (range 3.3-29.0) and 1.7 (0.6-7.2)  nmol/mL, respectively (p < 0.0001). In terms of renal function at T0 and T1, serum creatinine levels (1.1 ± 0.5 vs. 0.9 ± 0.5 mg/dL, respectively; p < 0.0001), creatinine clearance (69.7 ± 32.2 vs. T1 = 78.5 ± 33.9 mL/min/1.73 m(2), respectively; p = 0.006), and cystatin c level (1.33 ± 0.53 vs. 1.15 ± 0.54 mg/l, respectively; p = 0.0057) were all significantly different at these two time points. Serum creatinine measurements at 6 (T -6) and 3 months (T -3) before NAC initiation and at 3 (T +3) and 6 months (T +6) after NAC had been withdrawn were also evaluated. CONCLUSION: During the 3-month period that our 23 cystinosis patients were treated with NAC, oxidative stress was reduced and renal function significantly improved. No side-effects were detected. Larger and controlled studies are needed to confirm these findings.

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)2 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). Burosumab (anti-FGF23 antibody) has shown to be effective and safety in the clinical trials. METHODS: The current real-world collaborative study evaluated genetic, clinical and laboratory data of XLH Brazilian adult patients treated with burosumab. RESULTS: Nineteen unrelated patients were studied. Patients reported pain, limb deformities and claudication, before burosumab initiation. 78% of them were previously treated with conventional therapy. The severity of the disease was moderate to severe (15 patients with score >5). At the baseline, 3 patients presented NC (16.7%) and 12 HPT (63%). After 16 ± 8.4 months under burosumab, we observed a significant: increase in stature (p = 0.02), in serum phosphate from 1.90 ± 0.43 to 2.67 ± 0.52 mg/dL (p = 0.02); in TmP/GFR from 1.30 ± 0.46 to 2.27 ± 0.64 mg/dL (p = 0.0001), in 1,25 (OH)2 D from 50.5 ± 23.3 to 71.1 ± 19.1 pg/mL (p = 0.03), and a decrease in iPTH from 86.8 ± 37.4 pg/mL to 66.5 ± 31.1 (p = 0.002). Nineteen variants were found (10 novel). HPT tended to develop in patients with truncated PHEX variants (p = 0.06). CONCLUSIONS: This study confirms the efficacy and safety of burosumab on XLH adult patients observed in clinical trials. Additionally, we observed a decrease in iPTH levels in patients with moderate to severe HPT at the baseline.

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. METHODS: We evaluated the clinical and mutational profile of this cohort and performed a systematic review of BS mutations from worldwide cohorts. RESULTS: Twenty-two patients were included; Gitelman syndrome was diagnosed in 2 siblings with antenatal BS and congenital chloride diarrhea in 1 girl. BS was confirmed in 19 patients: BS type 1 in 1 boy (antenatal BS); BS type 4a in 1 girl and BS type 4b in 1 girl, both of them with antenatal BS and neurosensorial deafness; BS type 3 (CLCNKB mutations): 16 cases. The deletion of the entire CLCNKB (1-20 del) was the most frequent variant. Patients carrying the 1-20 del presented earlier manifestations than those with other CLCNKB-mutations and the presence of homozygous 1-20 del was correlated with progressive chronic kidney disease. The prevalence of the 1-20 del in this BS Brazilian cohort was similar to that of Chinese cohorts and individuals of African and Middle Eastern descent from other cohorts. CONCLUSION: This study expands the genetic spectrum of BS patients with different ethnics, reveals some genotype/phenotype correlations, compares the findings with other cohorts, and provides a systematic review of the literature on the distribution of BS-related variants worldwide.

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. We report 3 cases of dRTA in patients with different autoimmune diseases and review the pathophysiological mechanisms already described. CASE REPORT The first case involved a 29-year-old woman with autoimmune hepatitis. She had metabolic acidosis with persistent hypokalemia, and a kidney stone was also identified. The second case involved a 67-year-old woman diagnosed with rheumatoid arthritis. She had metabolic acidosis with hypokalemia. The third case involved a 30-year-old woman with Sjögren syndrome and persistent metabolic acidosis. In addition to the presence of metabolic acidosis with a normal plasma anion gap, all 3 patients exhibited urine with a supraphysiologic pH (above 5.3). CONCLUSIONS Autoimmune diseases may be associated with deficits in urinary acidification with consequent metabolic acidosis and, therefore, systemic repercussions. This association must be remembered and researched because correct diagnosis and treatment will serve to reduce complications.

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). Randomized controlled clinical studies and studies with real-life data added to the authors' experience were considered for this review. The result of this consensus was to help manage patient and physician expectations regarding treatment outcomes. Thus, this consensus document recommends the investigation of the pediatric family members of an index case, as well as cases with suggestive clinical signs. From the diagnosis, assess all possible FD impairments and grade through scales. From an extensive review of the literature including pediatric protocols and particularly evaluating pediatric cases from general studies, it can be concluded that the benefits of early treatment are great, especially in terms of neuropathic pain and renal impairment parameters and outweigh the possible adverse effects that were mainly manifested by infusion reactions.

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). The review considered randomized clinical trials, real-world data studies, and the expertise of its authors. The purpose of this consensus statement is to help manage patient and physician expectations concerning the outcomes of treatment. Our recommendations must be interpreted within the context of available evidence. The decisions pertaining to each individual case must be made with the involvement of patients and their families and take into account not only the potential cost of treatment, but also concurrent conditions and personal preferences. The Comdora intends to update these recommendations regularly so as to reflect recent literature evidence, real-world data, and appreciate the professional experience of those involved. This consensus document establishes clear criteria for the diagnosis of FD and for when to start or stop specific therapies or adjuvant measures, to thus advise the medical community and standardize clinical practice.

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 2.2 ± 1.0 years, 53% male, 73% White) were enrolled and treated with DR-cysteamine capsules for up to 18 months. Patients had clinically meaningful decreases in WBC cysteine concentration during treatment (3.2 ± 3.0 nmol ½ cystine/mg protein at Day 1 to 0.8 ± 0.8 nmol ½ cystine/mg protein at study exit), and anthropometric data improvements were consistently observed in height, weight and body surface area. Additionally, estimated glomerular filtration rate increased from 55.93 ± 22.43 ml/min/1.73 m2 at baseline to 63.79 ± 21.44 ml/min/1.73 m2 at study exit. Pharmacokinetic/Pharmacodynamic results support the use of the same starting, escalation, and maintenance doses according to body surface for children aged <6 years that are currently recommended in adults and older children. All patients experienced ≥1 adverse event(s) with vomiting (80%) and upper respiratory tract infection (53%) most frequently reported. Based on our study, patients <6 years of age with nephropathic cystinosis without prior treatment can safely and effectively initiate treatment with DR-cysteamine, a delayed-release form of cysteamine bitartrate that can be given every 12 h.

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). Methods: Analysis of clinical, laboratory, genetic and treatment data from patients inserted in the BRaHUS, from 2017 to 2020, as an initiative of the Rare Diseases Committee of the Brazilian Society of Nephrology. Results: The cohort consisted of 75 patients (40 adults and 35 pediatric). There was a predominance of women (56%), median age at diagnosis of 20.7 years and a positive family history in 8% of cases. Renal involvement was observed in all cases and 37% had low C3 levels. In the <2 years of age group, males were predominant. Children presented lower levels of hemoglobin (P = .01) and platelets (P = .003), and higher levels of lactate dehydrogenase (LDH) (P = .004) than adults. Genetic analysis performed in 44% of patients revealed pathogenic variants in 66.6% of them, mainly in CFH and the CFHR1-3 deletion. Plasmapheresis was performed more often in adults (P = .005) and 97.3% of patients were treated with eculizumab and its earlier administration was associated with dialysis-free after 3 months (P = .08). Conclusions: The cohort of BRaHUS was predominantly composed of female young adults, with renal involvement in all cases. Pediatric patients had lower hemoglobin and platelet levels and higher LDH levels than adults, and the most common genetic variants were identified in CFH and the CFHR1-3 deletion with no preference of age, a peculiar pattern of Brazilian patients.

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. We included patients with aHUS whose eculizumab therapy underwent unplanned discontinuation for at least 30 days between January 1st, 2016 and December 31st, 2019 during the maintenance phase of treatment. Relapse was defined by the development of thrombocytopenia, hemolytic anemia, acute kidney injury or thrombotic microangiopathy (TMA) in a kidney biopsy. RESULTS: We analyzed 25 episodes of exposure to risk of relapse, from 24 patients. Median age was 33 (6-53) years, 18 (72%) were female, 9 (36%) had a functioning renal graft, 5 (20%) were undergoing dialysis. CFH variant was found in 8 (32%) episodes. There were 11 relapses. The risk of relapse was 34%, 44.5% and 58% at 114, 150 and 397 days, respectively. No baseline variable was related to relapse in Cox multivariate analysis, including CFH variant. CONCLUSIONS: In this study, the cumulative incidence of aHUS relapse at 397 days was 58% after eculizumab interruption. The presence of complement variant does not seem to be associated with a higher relapse rate. The eculizumab interruption was deemed not safe, considering that the rate of relapse was high.

Report of a Brazilian multicenter study on nephropathic cystinosis.

INTRODUCTION: The Brazilian Multicenter Nephropathic Study Group, founded in 1999, is currently composed of 16 pediatric nephrology units, which are coordinated by the Pediatric Nephrology Unit of Instituto da Criança--HCFMUSP. This Study Group intends to better know our patients, their special characteristics and facilitates the treatment. OBJECTIVE: To present an update on the demographics of the ongoing study participants with interest on renal function status, response to therapy, and extra-renal complications. METHODS: Patient recruitment to the study is based on informed consent and has been supported by the Brazilian Society of Nephrology, by the creation of an electronic homepage and by the participation in medical meetings and publications in medical periodicals. Our study protocol involves the initial and follow-up questionnaire, the measurement of intraleukocyte cystine content, initiation and follow-up therapy with cysteamine, and clinical patient follow-up based on a protocol of subsidiary exams. RESULTS: We identified 102 patients (42 females) with nephropathic cystinosis in Brazil since 1999. Forty-six children are followed at the Instituto da Criança/SP, 15 at the Hospital Pequeno Príncipe/PR, 12 at the UNICAMP/SP, 10 at the Unidade de Transplante Renal - HCFMUSP/SP and 3 at the Santa Casa/SP; the remaining patients are followed at the Instituto da Criança and at their respective doctors' offices in different nephrology services in Brazil. Of these patients, 23/102 (22.5%) have normal renal function, 19/102 (18.6%) are in chronic renal failure with conservative treatment, 26/102 are on dialysis (18 on peritoneal dialysis and 8 on hemodialysis), and 34/102 received a renal transplant. The extra-renal involvement diagnosed was: hypothyroidism in 63 patients, diabetes mellitus in 8 patients, muscular involvement in 7 patients, a compromised central nervous system in 5 patients, hepatic complications in 5 patients, and deglutition dysfunction in 2 patients. During this period, 10/102 patients died. Cysteamine has been used by 81/102 patients (20 children started the therapy under 2 years of age). Growth parameters were improved by cysteamine, mainly in the youngest patients. We used recombinant growth hormone in 15 patients with persistent low growth velocity and stature z score under 2.5%. We could also observe a delay in appearance of extra-renal complications in patients receiving cysteamine. CONCLUSION: Our study demonstrates the importance of a multi-center study for recruitment, diagnosis and management of rare diseases. This study promotes access to the adequate treatment with profound impact on the quality of life.

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. Non-essential decision-making procedures should be postponed. In stable cases under appropriate treatment, we must choose to contact our patients remotely, using teleconsultations and home exam collections (if possible). In the presence of a symptom or sign of decompensation of the underlying disease, or infection with Sars-cov-2, advise the patient to seek medical assistance. The patient should not be waiting to get worse. Changes to the prescription should only be made on a scientific basis. Dosage suspension or change is not recommended, even in cases in which the patient needs to go to a center to receive his medication; in this case, the infusion center must follow the recommendations of the Ministry of Health. If the patient develops Covid-19 and uses any drugs, check the need for dose adjustment of the routine medications. Avoid the use of antimetabolics and anti-CD20 in patients with Covid-19, as they reduce viral clearance and predispose to bacterial infections. Contact between the patient and the medical team is essential; changes are recommended only with specialized medical guidance.

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. After more than 20 years as a care center for these patients, the authors propose a follow-up protocol, which has been used with improvement in the quality of care and consists of a multidisciplinary approach, including care provided by a physician, nurse, psychologist, nutritionist and social worker. In this paper, each field objectively exposes how to address points that involve the stages of diagnosis and its communication with the patient and their relatives or guardians, covering the particularities of the disease and the treatment, the impact on the lives of patients and families, the approach to psychological and social issues and guidelines on medications and diets. This protocol could be adapted to the follow-up of patients with other rare diseases, including those with renal involvement. This proposal is expected to reach the largest number of professionals involved in the follow-up of these patients, strengthening the bases for the creation of a national protocol, observing the particularities of each case.

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) / Recomendações para o diagnóstico e manejo de pacientes pediátricos com doença de Fabry: documento do comitê de doenças raras da Sociedade Brasileira de Nefrologia (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). Randomized controlled clinical studies and studies with real-life data added to the authors' experience were considered for this review. The result of this consensus was to help manage patient and physician expectations regarding treatment outcomes. Thus, this consensus document recommends the investigation of the pediatric family members of an index case, as well as cases with suggestive clinical signs. From the diagnosis, assess all possible FD impairments and grade through scales. From an extensive review of the literature including pediatric protocols and particularly evaluating pediatric cases from general studies, it can be concluded that the benefits of early treatment are great, especially in terms of neuropathic pain and renal impairment parameters and outweigh the possible adverse effects that were mainly manifested by infusion reactions.

A doença de Fabry (DF) é uma doença genética, com herança ligada ao cromossomo X, devido a variantes no gene GLA que codifica a enzima α-galactosidase A (α-GAL). O propósito do presente estudo foi criar um consenso objetivando padronizar as recomendações em relação ao acometimento renal da DF com orientações sobre o diagnóstico, rastreamento, e tratamento de pacientes pediátricos. Esse consenso é uma iniciativa do Comitê de Doenças Raras (Comdora) da Sociedade Brasileira de Nefrologia (SBN). Foram considerados para esta revisão estudos clínicos controlados randomizados e estudos com dados de vida real somados à experiência dos autores. O resultado desse consenso foi auxiliar no gerenciamento das expectativas de pacientes e médicos quanto aos resultados do tratamento. Assim, este documento de consenso recomenda a investigação dos familiares pediátricos de um caso índice, assim como de casos com clínica sugestiva. A partir do diagnóstico, avaliar todos os possíveis acometimentos da DF e graduar através de escalas. A partir de uma revisão extensa da literatura incluindo protocolos pediátricos e avaliando particularmente os casos pediátricos de estudos gerais, pode-se concluir que os benefícios do tratamento precoce são grandes, principalmente quanto aos parâmetros de dor neuropática e do acometimento renal, e suplantam os possíveis adversos que foram sobretudo manifestados por reações infusionais.

Brazilian consensus recommendations for the diagnosis, screening, and treatment of individuals with fabry disease: Committee for Rare Diseases - Brazilian Society of Nephrology/2021 / Consenso brasileiro de doença de fabry: recomendações de diagnóstico, triagem e tratamento. Comitê de doenças raras (Comdora) - SBN/2021

Abstract 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). The review considered randomized clinical trials, real-world data studies, and the expertise of its authors. The purpose of this consensus statement is to help manage patient and physician expectations concerning the outcomes of treatment. Our recommendations must be interpreted within the context of available evidence. The decisions pertaining to each individual case must be made with the involvement of patients and their families and take into account not only the potential cost of treatment, but also concurrent conditions and personal preferences. The Comdora intends to update these recommendations regularly so as to reflect recent literature evidence, real-world data, and appreciate the professional experience of those involved. This consensus document establishes clear criteria for the diagnosis of FD and for when to start or stop specific therapies or adjuvant measures, to thus advise the medical community and standardize clinical practice.

Resumo A doença de Fabry (DF) é uma doença genética, com herança ligada ao cromossomo X, que ocorre devido a variantes no gene GLA que codifica a enzima α-galactosidase A (α-GAL). O propósito do presente estudo foi criar um consenso objetivando padronizar as recomendações em relação ao acometimento renal da DF com orientações sobre o diagnóstico, rastreamento e tratamento de pacientes adultos e pediátricos. Esse consenso é uma iniciativa do Comitê de Doenças Raras (Comdora) da Sociedade Brasileira de Nefrologia (SBN). Foram considerados para esta revisão estudos clínicos controlados randomizados e estudos com dados de vida real somado à experiência dos autores. O resultado desse consenso foi auxiliar no gerenciamento das expectativas de pacientes e médicos quanto aos resultados do tratamento. Nossas recomendações devem ser interpretadas no contexto das evidências e ressaltando que as decisões finais devem ser tomadas individualmente, em uma decisão conjunta com o paciente e familiares, considerando os custos envolvidos, não apenas financeiros, doenças concomitantes e preferências pessoais. O Comdora pretende atualizar essas recomendações regularmente, e assim seguir novas evidências na literatura, considerar dados de vida real e valorizar a experiência profissional dos envolvidos. Esse consenso estabelece critérios claros para o diagnóstico da DF, início e interrupção de terapia específica e de medidas adjuntas, orientando a comunidade médica e uniformizando condutas.

COMDORA-SBN recommendations for patients with rare kidney diseases in relation to the Covid-19 pandemic / Recomendações do COMDORA-SBN a pacientes portadores de doenças renais raras em relação à pandemia de Covid-19

ABSTRACT 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. Non-essential decision-making procedures should be postponed. In stable cases under appropriate treatment, we must choose to contact our patients remotely, using teleconsultations and home exam collections (if possible). In the presence of a symptom or sign of decompensation of the underlying disease, or infection with Sars-cov-2, advise the patient to seek medical assistance. The patient should not be waiting to get worse. Changes to the prescription should only be made on a scientific basis. Dosage suspension or change is not recommended, even in cases in which the patient needs to go to a center to receive his medication; in this case, the infusion center must follow the recommendations of the Ministry of Health. If the patient develops Covid-19 and uses any drugs, check the need for dose adjustment of the routine medications. Avoid the use of antimetabolics and anti-CD20 in patients with Covid-19, as they reduce viral clearance and predispose to bacterial infections. Contact between the patient and the medical team is essential; changes are recommended only with specialized medical guidance.

RESUMO Durante a pandemia da Covid-19, fica a questão de como manter o atendimento adequado aos portadores de outras doenças. O Comitê de Doenças Raras (COMDORA) da SBN neste documento dá algumas orientações ao atendimento de pacientes com doenças renais raras. Estes pacientes devem seguir as recomendações destinadas à população geral tendo em mente que, por serem portadores de doença renal crônica, estão incluídos no grupo de risco para desfechos mais graves, caso venham a desenvolver a Covid-19. Procedimentos não essenciais para tomada de decisão devem ser adiados. Deve-se optar por contatos a distância, como teleconsultas, e coletas de exames domiciliares (se possível) nos casos estáveis sob tratamento adequado. Na presença de sintoma ou sinal de descompensação da doença de base ou infecção pelo Sars-cov-2, orientar o paciente a procurar a equipe médica. O paciente não deve ficar esperando o quadro agravar-se. Alterações na prescrição só devem ser feitas com embasamento científico. Não se recomenda a suspensão ou alteração posológica, mesmo nos casos em que o paciente necessita ir a um centro para receber sua medicação; neste caso o centro de infusão deve seguir as recomendações do Ministério da Saúde. Caso o paciente desenvolva a Covid-19 e faça uso de alguma droga, verificar a necessidade de ajuste nas doses dos medicamentos rotineiros. Evitar o uso de antimetabólicos e antiCD20 nos pacientes com a Covid-9, por reduzirem o clareamento viral e predisporem a infecções bacterianas. O contato entre paciente e equipe médica é essencial; alterações são recomendadas apenas com orientação médica especializada.

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. aHUS is a diagnosis of exclusion of other causes of MAT. The treatment of aHUS with plasma therapy, results in most cases with good shortterm response, especially hematological; however, it is a progressive and devastating disease and can lead to death and terminal chronic renal disease. Treatment with plasma displays great recurrence of long-term disease and renal insufficiency. Eculizumab, a monoclonal antibody anti-C5, has been associated with hematological remission, benefits on renal function and no need of plasma therapy.