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Introduction: Hemoglobinopathy Sβ-thalassemia (HbSβ-thal) has a wide range of clinical and laboratory severity. There is limited information on the natural history of HbSβ-thal and its modulating factors. We described the molecular, hematological, and clinical characteristics of a cohort of children with HbSβ-thal and estimated its incidence in Minas Gerais, Brazil., Methods: Laboratory and clinical data were retrieved from medical records. Molecular analysis was performed by HBB gene sequencing, PCR-RFLP, gap-PCR, and MLPA., Results: Eighty-nine children were included in the study. Fourteen alleles of β-thal mutations were identified. The incidence of HbSβ-thal in the state was 1 per 22,250 newborns. The most common β S -haplotypes were CAR and Benin. The most frequent β thal -haplotypes were V, II, and I. Coexistence of 3.7 kb HBA1/HBA2 deletion was present in 21.3 % of children. β-thalassemia mutations were associated with several clinical and laboratory features. In general, the incidence of clinical events per 100 patient-years was similar for children with HbSβ 0 -thal, IVS-I-5 G>A, and IVS-I-110 G>A. Children with HbSβ + -intermediate phenotypes had a more severe laboratory and clinical profile when compared with those with HbSβ + -mild ones. β S -haplotypes and α-thalassemia did not meaningfully influence the phenotype of children with HbSβ-thal., Conclusion: The early identification of β-thalassemia alleles may help the clinical management of these children., Competing Interests: Conflicts of interest All authors declare that they have no conflict of interest., (Copyright © 2023 Associação Brasileira de Hematologia, Hemoterapia e Terapia Celular. Published by Elsevier España, S.L.U. All rights reserved.)

Aim: The aim of this study was to compare novel kidney injury biomarkers in sickle cell anemia (SCA) children with and without albuminuria or glomerular hyperfiltration. Materials & methods: A total of 358 Brazilian children with SCA were studied. Fifteen kidney injury biomarkers in urine were measured. Albuminuria was defined as urine albumin/creatinine ratio >100 mg/g. Glomerular hyperfiltration was defined as estimated glomerular filtration rate ≥140 ml/min/1.73 m 2 . Results: After adjustment for age, sex and modifying therapies in use, EGF and collagen IV urinary levels were associated with albuminuria. Renin and clusterin levels were associated with hyperfiltration. Conclusion: Levels of novel kidney injury biomarkers were associated with albuminuria and hyperfiltration in Brazilian children with SCA, suggesting concomitant structural and functional abnormalities.

Sickle cell anemia (SCA) is an important cause of chronic kidney disease, but its pathophysiology is not completely understood. The aim of this study was to compare inflammatory biomarkers in urine samples of SCA children with and without albuminuria, and to explore correlations with renin-angiotensin system (RAS) molecules. A cross-sectional study of 213 children selected from the Minas Gerais state cohort were assigned to two groups: Group 1-89 children with SCA who had albuminuria; Group 2-124 children with SCA and normal albuminuria matched by age and sex with group 1. A subset of 89 children was prospectively followed for a median time of 1.1 year. Inflammatory biomarkers (chemokines and cytokines) in urine were measured using cytometric beads array, and RAS molecules were measured by ELISA. Children with albuminuria had significantly higher urinary levels of IP-10/CXCL10, MCP-1/CCL2, MIG/CXCL9, IL-8/CXCL8, IL-12p70, TNF, IL-10, and IL-6 than patients with normal albuminuria. In the correlation analysis, albumin/creatinine ratio was significantly and positively correlated with IP-10/CXCL10, MCP-1/CCL2, MIG/CXCL9, IL-8/CXCL8, TNF, IL-10, and IL-6. Significant correlations were found between inflammatory and RAS molecules. In the prospective analysis, cumulative risk of persistent albuminuria was higher for children with urinary levels of IP-10/CXCL10 or IL-6 above the 50th percentile. Our data showed that inflammatory markers and RAS molecules might contribute to the occurrence of albuminuria in children with SCA, suggesting that both pathways interact in sickle cell nephropathy., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Objectives: Hemoglobin SC is the second most common variant of sickle-cell disease worldwide, after hemoglobin SS. The objectives of the study were to describe the clinical and laboratory characteristics of hemoglobin SC disease in children from a newborn screening program and treated at a blood center., Methodology: This study assessed a cohort of 461 infants born between 01/01/1999 and 12/31/2012 and followed-up until 12/31/2014. Clinical events were expressed as rates for 100 patient-years, with 95% confidence intervals. Kaplan-Meier survival curves were created., Results: The median age of patients was 9.2 years; 47.5% were female. Mean values of blood tests were: hemoglobin, 10.5g/dL; reticulocytes, 3.4%; white blood cells, 11.24×10 9 /L; platelets, 337.1×10 9 /L; and fetal hemoglobin, 6.3%. Clinical events: acute splenic sequestration in 14.8%, blood transfusion 23.4%, overt stroke in 0.2%. The incidence of painful vaso-occlusive episodes was 51 (48.9-53.4) per 100 patient-years and that of infections, 62.2 episodes (59.8-64.8) per 100 patient-years. Transcranial Doppler ultrasonography (n=71) was normal given the current reference values for SS patients. Hydroxyurea was given to ten children, all of whom improvement of painful crises. Retinopathy was observed in 20.3% of 59 children who underwent ophthalmoscopy. Avascular necrosis was detected in seven of 12 patients evaluated, predominantly in the left femur. Echocardiogram compatible with pulmonary hypertension was recorded in 4.6% of 130 children, with an estimated average systolic pulmonary artery pressure of 33.5mmHg. The mortality rate from all causes was 4.3%., Conclusions: Clinical severity is variable in SC hemoglobinopathy. Several children have severe manifestations similar to those with SS disease., (Copyright © 2018 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.)

Objective: To analyze acute splenic sequestration (ASS) in children with sickle cell anemia diagnosed through a newborn screening program in the state of Minas Gerais, Brazil, and followed up at the hematology center in the city of Belo Horizonte, Minas Gerais, Brazil., Methods: Retrospective cohort of 255 children with sickle cell anemia (Hb SS/Sbeta(0)) born between January 01, 2000, and December 31, 2004, and followed up until December 31, 2006. Data were abstracted from the patients' medical records., Results: A total of 89 patients had 173 episodes of ASS (10.2 first episodes per 100 patient-years); 75% of the first episodes occurred before 2 years of age. The estimated probability of occurrence of the first episode of ASS during the study period was 40%. Recurrence rate reached 57.3%. After the first episode, splenectomy was indicated in only 12.4% of the cases; after the second, in 60.4% of the cases. After the third episode, 41.7% of the patients remained under clinical observation. The median time between indication for splenectomy and the actual surgical procedure was 2 months. During the intervening period, 37.2% of the children suffered a new episode of ASS and one child died. Case-fatality rate was 1.1% for the first episode and 7.8% for the subsequent episodes. Among a total of 255 children, 19 died: 36.8% due to infections and 26.3% after ASS., Conclusions: ASS is relatively common in sickle cell anemia, mainly in the first 2 years of life; relapse occurs in more than half of the cases. Conservative management instead of immediate splenectomy was the method of choice. Although the case-fatality rate was low, ASS was the second most common cause of death. These results disclose some fragilities of the health system in the state of Minas Gerais and the need for better professional education to approach ASS crises.