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.

Dengue infection in kidney transplant recipients: clinical course and its impact on renal function / Infecção por dengue em receptores de transplante renal: curso clínico e seu impacto na função renal

Abstract Introduction: Kidney transplant recipients (KTR) are at increased risk for dengue virus (DENV) infection. The aim of this study was to outline the clinical presentation and laboratory profile of DENV infection in KTR and its impact on renal function. Methods: This was a retrospective study of KTR diagnosed with DENV infection. Adult patients who visited Santa Casa de Belo Horizonte Nephrology Center between April and September 2019 were included. Patients who did not sign the Informed Consent were excluded. Data were collected from the database and medical records. The study was approved by the local Institutional Ethics Committee and the Informed Consent was obtained. Results: Nineteen KTR were evaluated. The main signs and symptoms were myalgia, headache/retro-orbital pain, fever, and gastrointestinal symptoms. Two patients had acute cholecystitis without calculus, three experienced pleural and/or pericardial effusion, and one developed acute myocarditis. All patients were under immunosuppression with prednisone, tacrolimus, and mycophenolate, and most were not receiving induction therapy. Temporary suspension/reduction of immunosuppression was required in 58% of patients and leukopenia was the most common reason. Thrombocytopenia was common and 58% of patients developed acute kidney injury. All patients recovered renal function. Conclusions: DENV infection in KTR patients seems to follow a similar course as in the general population. Although there was no control group, we suspect that immunosuppression, preexisting kidney disease or type of donor was not a determining factor in most patients. Transient renal dysfunction was common but reversible. No patient experienced death or graft loss.

Resumo Introdução: Receptores de transplante renal (RTR) apresentam maior risco de infecção pelo vírus da dengue (DENV). O objetivo deste estudo foi delinear apresentação clínica e perfil laboratorial da infecção por DENV em RTR e seu impacto na função renal. Métodos: Este foi um estudo retrospectivo de RTR diagnosticados com infecção por DENV. Incluiu-se pacientes adultos que estiveram no Centro Nefrológico da Santa Casa de Belo Horizonte entre Abril/Setembro, 2019. Foram excluídos pacientes que não assinaram o Termo de Consentimento Livre e Esclarecido. Dados foram coletados do banco de dados e registros médicos. O estudo foi aprovado pelo Comitê de Ética Institucional local e obteve-se o Consentimento Livre e Esclarecido. Resultados: Avaliou-se dezenove RTR. Principais sinais e sintomas foram mialgia, cefaleia/dor retro-orbital, febre, sintomas gastrointestinais. Dois pacientes apresentaram colecistite aguda sem cálculo, três sofreram derrame pleural e/ou pericárdico, um desenvolveu miocardite aguda. Todos os pacientes estavam sob imunossupressão com prednisona, tacrolimus, micofenolato. A maioria não estava recebendo terapia de indução. Suspensão/redução temporária da imunossupressão foi necessária em 58% dos pacientes e leucopenia foi a razão mais comum. Trombocitopenia foi comum e 58% dos pacientes desenvolveram lesão renal aguda. Todos recuperaram a função renal. Conclusões: A infecção por DENV em pacientes RTR parece seguir um curso semelhante ao da população em geral. Embora não houvesse grupo controle, suspeitamos que imunossupressão, doença renal preexistente ou tipo de doador não foram fator determinante na maioria dos pacientes. Disfunção renal transitória foi comum, mas reversível. Nenhum paciente veio ao óbito ou sofreu perda do enxerto.

Dengue infection in kidney transplant recipients: clinical course and its impact on renal function.

INTRODUCTION: Kidney transplant recipients (KTR) are at increased risk for dengue virus (DENV) infection. The aim of this study was to outline the clinical presentation and laboratory profile of DENV infection in KTR and its impact on renal function. METHODS: This was a retrospective study of KTR diagnosed with DENV infection. Adult patients who visited Santa Casa de Belo Horizonte Nephrology Center between April and September 2019 were included. Patients who did not sign the Informed Consent were excluded. Data were collected from the database and medical records. The study was approved by the local Institutional Ethics Committee and the Informed Consent was obtained. RESULTS: Nineteen KTR were evaluated. The main signs and symptoms were myalgia, headache/retro-orbital pain, fever, and gastrointestinal symptoms. Two patients had acute cholecystitis without calculus, three experienced pleural and/or pericardial effusion, and one developed acute myocarditis. All patients were under immunosuppression with prednisone, tacrolimus, and mycophenolate, and most were not receiving induction therapy. Temporary suspension/reduction of immunosuppression was required in 58% of patients and leukopenia was the most common reason. Thrombocytopenia was common and 58% of patients developed acute kidney injury. All patients recovered renal function. CONCLUSIONS: DENV infection in KTR patients seems to follow a similar course as in the general population. Although there was no control group, we suspect that immunosuppression, preexisting kidney disease or type of donor was not a determining factor in most patients. Transient renal dysfunction was common but reversible. No patient experienced death or graft loss.

Thrombotic microangiopathy after kidney transplantation: Analysis of the Brazilian Atypical Hemolytic Uremic Syndrome cohort.

BACKGROUND: Atypical Hemolytic Uremic Syndrome (aHUS) is an ultra-rare disease that potentially leads to kidney graft failure due to ongoing Thrombotic Microangiopathy (TMA). The aim was evaluating the frequency of TMA after kidney transplantation in patients with aHUS in a Brazilian cohort stratified by the use of the specific complement-inhibitor eculizumab. METHODS: This was a multicenter retrospective cohort study including kidney transplant patients diagnosed with aHUS. We collected data from 118 transplant centers in Brazil concerning aHUS transplanted patients between 01/01/2007 and 12/31/2019. Patients were stratified into three groups: no use of eculizumab (No Eculizumab Group), use of eculizumab for treatment of after transplantation TMA (Therapeutic Group), and use of eculizumab for prophylaxis of aHUS recurrence (Prophylactic Group). RESULTS: Thirty-eight patients with aHUS who received kidney transplantation were enrolled in the study. Patients' mean age was 30 years (24-40), and the majority of participants was women (63% of cases). In the No Eculizumab Group (n = 11), there was a 91% graft loss due to the TMA. The hazard ratio of TMA graft loss was 0.07 [0.01-0.55], p = 0.012 in the eculizumab Prophylactic Group and 0.04 [0.00-0.28], p = 0.002 in the eculizumab Therapeutic Group. CONCLUSION: The TMA graft loss in the absence of a specific complement-inhibitor was higher among the Brazilian cohort of kidney transplant patients. This finding reinforces the need of eculizumab use for treatment of aHUS kidney transplant patients. Cost optimization analysis and the early access to C5 inhibitors are suggested, especially in low-medium income countries.