Publications by authors named "Koehl B"

Hydroxyurea decreases painful events among children with sickle cell disease (SCD) but could increase the risk of infections in treated patients through leucopenia. We performed a case-control study, comparing hydroxyurea treatment for SCD in cases with an invasive bacterial infection and in controls without infection. No difference was found.

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While sickle cell anemia (SCA) and hereditary spherocytosis (HS) share common features of increased spleen erythrophagocytosis due to increased red blood cell (RBC) turnover, SCA is specifically characterized by susceptibility to infections. In this study, histological lesions in the spleens of pediatric patients with SCA were analyzed, in close correlation with past clinical history and comparatively to HS, healthy and transfused β-thalassemia patients (TDT). An evaluation of red pulp elementary lesions (red pulp fibrosis, iron deposition, number of Gandy-Gamna, and RBC trapping) combined into a severity score was established, as well as B-cell follicles analysis.

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Background: Sickle cell disease (SCD) is one of the most frequent inherited diseases in the world. Over the last decades, in high-income countries, an important decrease in mortality have been observed due to the improvement of care. However, children with SCD can become critically ill and require admission in Pediatric Intensive Care Units (PICU).

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Obstructive sleep apnea (OSA) is common in sickle cell disease (SCD) despite the absence of overweight, suggesting a specific pathophysiology. We previously showed that otherwise healthy children with increased pharyngeal compliance, a main endotype of OSA, exhibited decreased sympathetic modulation. Our objective was to assess whether modifications of heart rate variability (HRV) and compliance are associated in SCD.

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Article Synopsis
  • * A study analyzing 25 ischemic strokes in 1,500 children with SCD from 2007 to 2020 found that 52% had CA, while 48% did not, with older patients more likely to have strokes without CA.
  • * The strokes in patients without CA often involved different underlying causes and affected a different demographic, suggesting that long-term transfusion therapy may not be needed for these patients.
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Background: An important prevalence (32%-45%) of masked hypertension has been reported in children with sickle cell disease (SCD). Stroke screening is well established using transcranial Doppler (TCD) ultrasound. The objectives of our proof-of-concept study in childhood SCD were to evaluate the prevalence of hypertension and its relationships with cerebral vasculopathy (TCD velocity) and to further evaluate in a subgroup of children the correlations of cardiovascular autonomic nervous system indices with TCD velocity.

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Background: Children with sickle cell disease (SCD) are at a high risk of invasive bacterial infections (IBI). Universal penicillin prophylaxis and vaccination, especially against Streptococcus pneumoniae, have deeply changed its epidemiology. Analysis of IBI in children with SCD in a post-13-valent pneumococcal vaccine era is limited.

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Background: Acute chest syndrome (ACS) is a life-threatening complication of sickle cell disease (SCD). Although respiratory pathogens are frequently detected in children with ACS, their respective role in triggering the disease is still unclear. We hypothesized that the incidence of ACS followed the unprecedented population-level changes in respiratory pathogen dynamics after COVID-19-related nonpharmaceutical interventions (NPIs).

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In children with sickle cell anemia (SCA), early splenic complications can require splenectomy, but the benefit-to-risk ratio and the age at which splenectomy may be safely performed remain unclear. To address this question, we analyzed the rate of post-splenectomy events in children with SCA splenectomized between 2000-2018 at the Robert Debré University Hospital, Paris, France. A total of 188 children underwent splenectomy, including 101 (11.

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Intracellular uptake of adenosine is essential for optimal erythroid commitment and differentiation of hematopoietic progenitor cells. The role of adenosine signaling is well documented in the regulation of blood flow, cell proliferation, apoptosis, and stem cell regeneration. However, the role of adenosine signaling in hematopoiesis remains unclear.

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Blood phenotypes are defined by the presence or absence of specific blood group antigens at the red blood cell (RBC) surface, due to genetic polymorphisms among individuals. The recent development of genomic and proteomic approaches enabled the characterization of several enigmatic antigens. The choline transporter-like protein CTL2 encoded by the SLC44A2 gene plays an important role in platelet aggregation and neutrophil activation.

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Article Synopsis
  • Delayed haemolytic transfusion reaction (DHTR) is a serious condition that can happen in kids with sickle cell disease after they get a blood transfusion.
  • In a study of 41 children, DHTR usually showed up around 8 days after the transfusion, and 93% of the kids had painful crises.
  • Most kids had severe anemia and some faced major complications like breathing issues, liver problems, and strokes, but luckily, no one died. The study suggests needing better guidelines for treating DHTR in children.
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Hypoxia-mediated red blood cell (RBC) sickling is central to the pathophysiology of sickle cell disease (SCD). The signalling nucleoside adenosine is thought to play a significant role in this process. This study investigated expression of the erythrocyte type 1 equilibrative nucleoside transporter (ENT1), a key regulator of plasma adenosine, in adult patients with SCD and carriers of sickle cell trait (SCT).

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Aim: To describe the management of home oxygen therapy for infants with acute bronchiolitis through a home care network: Hospital at Home (HAH).

Methods: A retrospective observational study was carried out during two consecutive winters from 2012 to 2014.

Results: A total of 141 patients were eligible for home oxygen therapy, and 54 were discharged on home oxygen therapy through HAH.

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Importance: Acute chest syndrome (ACS) is one of the leading acute severe complications of sickle-cell disease (SCD). Although Streptococcus pneumoniae (S pneumoniae) is highly prevalent in children with SCD, its precise role in ACS is unclear. The efficacy of 13-valent pneumococcal conjugate vaccine (PCV13) implementation on ACS is still unknown.

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Post-lumbar puncture headache is the main adverse event from lumbar puncture and occurs in 3.5% to 33% of patients, causing functional and socio-professional disability. We searched the post-lumbar puncture headache literature and, based on this review and personal expertise, identified and addressed 19 frequently asked questions regarding post-lumbar puncture headache risk factors and prevention.

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Glycosylphosphatidylinositol (GPI) is a glycolipid that anchors >150 proteins to the cell surface. Pathogenic variants in several genes that participate in GPI biosynthesis cause inherited GPI deficiency disorders. Here, we reported that homozygous null alleles of PIGG, a gene involved in GPI modification, are responsible for the rare Emm-negative blood phenotype.

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Background: Many pediatric studies describe the association between biological parameters (BP) and severity of sickle cell disease (SCD) using different methods to collect or to analyze BP. This article assesses the methods used for collection and subsequent statistical analysis of BP, and how these impact prognostic results in SCD children cohort studies.

Methods: Firstly, we identified the collection and statistical methods used in published SCD cohort studies.

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