HemoTypeSC point-of-care testing shows high sensitivity with alkaline cellulose acetate hemoglobin electrophoresis for screening hemoglobin SS and SC genotypes

ABSTRACT Introduction: By providing timely actionable results for prompt management, point-of-care testing (POCT) kits have revolutionised medical care for various diseases, ranging from infectious diseases like malaria to genetic disorders, such as sickle cell disease (SCD). They are, however, underutilised in the diagnosis of SCD in developing countries, where the need is greatest. Objective: The study was aimed at assessing the sensitivity of HemoTypeSC POCT among a cohort of children with SCD, previously diagnosed by Alkaline cellulose acetate hemoglobin electrophoresis (ACAE), with or without high-performance liquid chromatography (HPLC). Methods: In this descriptive cross-sectional study, HemoTypeSC test was conducted on all participants and its sensitivity was determined by comparing results with those obtained using ACAE. Discordance was verified with HPLC. Results: One hundred and forty-five children aged one to 19 years were studied. There were 84 males and 61 females (male: female ratio = 1.4:1). The HemoTypeSC was able to correctly diagnose sickle cell anemia (SCA) and hemoglobin SC in all (100%) of the children tested. Conclusion: The HemoTypeSC shows high sensitivity in detecting SCA and hemoglobin SC. Hence, it is useful for targeted screening of individuals suspected of having SCD, leading to rapid diagnosis of these hemoglobinopathies, even in resource-constrained settings.

Patients with sickle cell disease are frequently excluded from the benefits of transcranial doppler screening for the risk of stroke despite extensive and compelling evidence / Pacientes com doença falciforme são frequentemente excluídos dos benefícios do screening com doppler transcraniano para avaliação do risco de acidente vascular cerebral, apesar de evidência extensa e convincente

ABSTRACT Transcranial doppler (TCD) is a strategic component of primary stroke prevention in children with sickle cell disease (SCD). This study was conducted to examine the TCD characteristics of children with SCD in nine different medical centers in Brazil. Methods: Transcranial doppler was performed in accordance with the Stroke Prevention Trial in Sickle Cell Anemia Protocol. Results: Of the 396 patients, 69.5% had homozygous SS hemoglobin. The TCD result was abnormal in 4.8%, conditional in 12.6%, inadequate in 4.3% and abnormally low in 1% of patients. The highest mean flow velocities were 121±23.83cm/s and 124±27.21cm/s in the left and right middle cerebral artery respectively. A total of 28.8% patients (mean age 9.19±5.92 years) were evaluated with TCD for the first time. Conclusions: The SCD patients were evaluated with TCD at an older age, representing an important missed opportunity for stroke prevention. Since TCD screening in patients with SCD is important to detect those at high risk for stroke, it is recommended that this screening should be made more readily available.

RESUMO Doppler transcraniano (DTC) é um componente estratégico da prevenção primária do acidente vascular cerebral (AVC) em crianças com doença falciforme (DF). Este estudo foi realizado para examinar as características do DTC de crianças com DF em nove centros médicos diferentes no Brasil. Métodos: DTC foi realizado de acordo com o protocolo de Stroke Prevention Trial in Sickle Cell Anemia Protocol (STOP). Resultados: Dos 396 pacientes avaliados, 69,5% eram homozigotos para hemoglobina SS. DTC foi anormal em 4,8%, condicional em 12,6%, inadequado em 5,3% e anormalmente baixo em 1%. As máximas velocidades de fluxo médio foram 121 ± 23,83cm/s e 124 ± 27,21 cm/s nas artérias cerebrais media esquerda e direita, respectivamente. Um total de 28,8% dos pacientes (média de 9,19 ± 5,92 anos) foram avaliados com o DTC pela primeira vez. Conclusões: Pacientes com DF foram avaliados com DTC numa idade considerada avançada, o que representa uma importante oportunidade perdida para a prevenção de AVC nessa população. Uma vez que a triagem com DTC em pacientes com DF é essencial para detectar aqueles com alto risco de AVC, recomenda-se que essa triagem seja amplamente disponível no país.

Haptoglobin gene polymorphisms and interleukin-6 and -8 levels in patients with sickle cell anemia

BACKGROUND: Haptoglobin genotypes, and interleukin-6 and -8 participate in the pathophysiology of sickle cell anemia. The expression of cytokines is regulated by genetic mechanisms however the effect of haptoglobin polymorphisms on these cytokines is not fully understood. This study aimed to compare the frequency of haptoglobin genotypes and the interleukin-6 and -8 concentrations in sickle cell anemia patients and controls to investigate the association between haptoglobin genotypes and cytokine levels.METHODS: Sixty sickle cell anemia patients and 74 healthy individuals were analyzed. Haptoglobin genotypes were determined by multiplex polymerase chain reaction, and the interleukin-6 and -8 levels by enzyme linked immunosorbent assay. The association between haptoglobin genotypes and cytokines was investigated by statistical tests.RESULTS:Hp2-1 was the most common genotype in both the cases and controls while Hp1-1 was less frequent among sickle cell anemia patients. Interleukin-6 and -8 levels were higher in patients than controls (p-value <0.0001). There was no significant difference in interleukin-6 and -8 concentrations between the genotypes (p-value >0.05). A similar trend was observed among the controls.CONCLUSION: Although, levels of interleukin-6 and -8 were higher in the sickle cell anemia patients, they appeared not to be related to the haptoglobin genotypes. Further investigations are necessary to identify factors responsible for increased secretion of the interleukin-6 and -8 pro-inflammatory cytokines in patients with sickle cell anemia.