RESUMO
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.
RESUMO
OBJECTIVE: To develop a clinical score for the early identification of chronic kidney disease (CKD) in children and adolescents. The early diagnosis of CKD in childhood allows the adoption of measures to slow the progression of the disease, thereby reducing morbidity and mortality. Nevertheless, the diagnosis is often made too late for proper patient management. STUDY DESIGN: We preformed a case-control study of a multicenter Brazilian sample of 752 pediatric patients; the study cases (n = 376) were CKD patients with a median estimated GFR of 37 (IQR = 22 to 57) ml/min/1.73 m2. The control group (n = 376) comprised age-, gender- and center-matched children who were followed for nonrenal diseases. Potential risk factors were investigated through a standard questionnaire that included symptoms, medical history, and a clinical examination. Two multivariable models (A and B) were fitted to assess predictors of the diagnosis of CKD. RESULTS: In model A, 9 variables were associated with CKD diagnosis: antenatal ultrasound with urinary malformation, recurrent urinary tract infection, polyuria, abnormal urine stream, nocturia, growth curve flattening, history of hypertension, foamy urine and edema (c-statistic = 0.938). Model B had the same variables as model A, except for the addition of the history of admission during the neonatal period and the exclusion of antenatal ultrasound variables (c-statistic = 0.927). CONCLUSIONS: The present scores may serve as a warning sign for CKD diagnosis in children among professionals working in the primary care setting where the symptoms associated with a risk of CKD may be overlooked.
