A study of 28 pregnant women with sickle cell disease and COVID-19: elevated maternal and fetal morbidity rates

Not available.

Relationship between paramacular thinning, cerebral vasculopathy, and hematological risk factors in sickle cell disease

Purpose

To identify risk factors for sickle cell maculopathy due to hematological parameters (especially anemia and hemolysis) or cerebral vasculopathy.

Methods

This retrospective study was conducted at a Referral Center. The follow-up included optical coherent tomography/optical coherent tomography angiography, neuro-radiological imaging, and a hematological assessment (hemoglobin, hemoglobin S level, reticulocytes, mean corpuscular volume, bilirubin, and lactate dehydrogenase).

Results

Hundred and thirty-two sickle cell patients were included. Maculopathy was observed in 127 eyes of SS patients and 10 eyes of SC patients (p < 0.001), unrelated to peripheral retinopathy. Cerebral vasculopathy was more frequent in SS patients (p < 0.001) and was also associated with the presence of maculopathy (p = 0.049), and it was related to peripheral retinopathy (p < 0.001). All biological parameters significantly differed according to the genotype (p < 0.001) but not according to the presence of cerebral vasculopathy or maculopathy. In the multivariate analysis, reticulocytes and bilirubin were associated with the presence of cerebral vasculopathy and maculopathy.

Conclusion

The data obtained were consistent with the role of anemia or hemolysis markers in cerebral vasculopathy and macular involvement. As a trend of hemolysis appears to be a risk factor for these complications, this validates the use of preventive plasmapheresis in these patients.

Epidemiology and disease burden of sickle cell disease in France: A descriptive study based on a French nationwide claim database

CONTEXT

Sickle cell disease (SCD) is a severe hematological disorder. The most common acute complication of SCD is vaso-occlusive crisis (VOC), but SCD is a systemic disease potentially involving all organs. SCD prevalence estimates rely mostly on extrapolations from incidence-based newborn screening programs, although recent improvements in survival may have led to an increase in prevalence, and immigration could account for a substantial number of prevalent patients in Europe. The primary objective of this study was to estimate SCD prevalence in France.

METHODS

A cross-sectional observational study was conducted using a representative sample of national health insurance data. SCD patients followed up in France between 2006 and 2011 were captured through hydroxyurea reimbursement and with the International Classification of Diseases (ICD-10) SCD specific code D570.1.2, excluding code D573 (which corresponds to sickle cell trait (SCT)). Nevertheless, we assumed that ICD-10 diagnosis coding for inpatient stays could be imperfect, with the possibility of SCT being miscoded as SCD. Therefore, prevalence was analyzed in two groups of patients [with at least one (G1) or two (G2) inpatient stay] based on the number of SCD-related inpatient stays in the six-year study period, assuming that SCT patients are rarely rehospitalized compared to SCD. The prevalence of SCD in the sample, which was considered to be representative of the French population, was then extrapolated to the general population. The rate of vaso-occlusive crisis (VOC) events was estimated based on hospitalizations, emergencies, opioid reimbursements, transfusions, and sick leave.

RESULTS

Based on the number of patients identified for G1 and G2, the 2016 French prevalence was estimated to be between 48.6 per 100,000 (G1) or 32,400 patients and 29.7 per 100,000 (G2) or 19,800 patients. An average of 1.51 VOC events per year were identified, with an increase frequency of 15 to 24 years of age. The average annual number of hospitalizations was between 0.70 (G1) and 1.11 (G2) per patient. Intensive care was observed in 7.6% of VOC-related hospitalizations. Fewer than 34% of SCD patients in our sample received hydroxyurea at any point in their follow-up. The annual average cost of SCD care is €5,528.70 (G1) to €6,643.80 (G2), with most costs arising from hospitalization and lab testing.

CONCLUSION

Our study estimates SCD prevalence in France at between 19,800 and 32,400 patients in 2016, higher than previously published. This study highlights the significant disease burden associated with vaso-occlusive events.

XPO1 regulates erythroid differentiation and is a new target for the treatment of β-thalassemia

β-thalassemia major (β-TM) is an inherited hemoglobinopathy caused by a quantitative defect in the synthesis of β-globin chains of hemoglobin, leading to the accumulation of free a-globin chains that aggregate and cause ineffective erythropoiesis. We have previously demonstrated that terminal erythroid maturation requires a transient activation of caspase-3 and that the chaperone Heat Shock Protein 70 (HSP70) accumulates in the nucleus to protect GATA-1 transcription factor from caspase-3 cleavage. This nuclear accumulation of HSP70 is inhibited in human β-TM erythroblasts due to HSP70 sequestration in the cytoplasm by free a-globin chains, resulting in maturation arrest and apoptosis. Likewise, terminal maturation can be restored by transduction of a nuclear-targeted HSP70 mutant. Here we demonstrate that in normal erythroid progenitors, HSP70 localization is regulated by the exportin-1 (XPO1), and that treatment of β-thalassemic erythroblasts with an XPO1 inhibitor increased the amount of nuclear HSP70, rescued GATA-1 expression and improved terminal differentiation, thus representing a new therapeutic option to ameliorate ineffective erythropoiesis of β-TM.

[Sickle cell trait complications: A case series of 6 patients]

INTRODUCTION

Patients with sickle cell trait (SCT) are commonly considered as asymptomatic carriers. However, some clinical manifestations may occur.

METHODS

Here we present a retrospective descriptive study about SCT subjects with at least one complication diagnosed in a sickle cell disease referral center, in Paris, between 2008 and 2019. We also performed a literature review on the complications of SCT subjects.

RESULTS

Six patients (between 19 and 65 years old) were included. SCT was already known only for 4 of them at the time of the complication. Four patients presented with a splenic infarct after a stay in high altitude or a plane trip, one of them was associated with papillary necrosis; one patient had isolated papillary necrosis, and the last one had splenic sequestration. These complications happened for most of them after exposure to an unusual situation of hypoxia or deshydratation. Five out of 6 patients had a marked elevated C reactive protein.

CONCLUSION

SCT may cause acute ischemic complications in a context of prolonged hypoxia or dehydration. The most commonly reported are the splenic infarct and the renal papillary necrosis. A study of hemoglobin should be considered in these clinical situations in patients with compatible ethnic origin.

[Current concepts on the physiopathology of adult-onset Still's disease]

PURPOSE

Adult-onset Still's disease (AOSD) is a rare systemic inflammatory disorder of unknown origin. It is characterized by hectic fever, evanescent rash, polyarthralgias or polyarthritis, sore throat, hepatosplenomegaly, lymphadenopathy, polynuclear leukocytosis, liver cytolysis, and high serum level of ferritin with low glycosylated fraction.

CURRENT KNOWLEDGE AND KEY POINTS

An increased serum level of ferritin, IL-8, IL-6, IL-18 and TNF-alpha indicates that macrophages are highly activated in AOSD. Interleukin 18 (IL-18) seems to be a key cytokine in the pathogenesis of AOSD. Serum IL-18 levels are increased in AOSD patients compared to other systemic inflammatory diseases such as rheumatoid arthritis and they are well correlated with serum ferritin levels and disease activity. IL-18 could cause acute liver injury and arthritis. Macrophages could be activated by infectious agents such as viruses and by an inadequate control of T cell response secondary to depressed Natural Killer lymphocyte function, similarly to that observed in systemic juvenile idiopathic arthritis. Sustained macrophage activation can lead to the hemophagocytic syndrome, a severe complication of both AOSD and systemic juvenile idiopathic arthritis.

FUTURE PROSPECTS

Cytotoxic cell functions should be probably studied in AOSD as they were in the hemophagocytic syndrome and systemic juvenile idiopathic arthritis because AOSD, characterised by a marked macrophage activation may be related to an immunological deficiency.

[Febrile form of ankylosing spondylitis]

INTRODUCTION

Ankylosing spondylitis is a chronic inflammatory disorder that is rarely associated with severe systemic manifestations.

EXEGESIS

We report the case of a 29-year-old man presenting with an atypical ankylosing spondylitis. The patient presented with a high spiking fever, a marked weight loss, and an unusual increase of acute phase response markers. Such features are rarely associated with ankylosing spondylitis and the review of the few similar reported cases in the literature showed that this presentation is usually associated with a severe disease course, and an asymmetrical joint involvement that is unresponsive to nonsteroidal anti-inflammatory agents.

CONCLUSION

Clinicians should be aware of this unusual presentation of ankylosing spondylitis, which should be included in the list of aetiologies of fever of unknown origin, to avoid useless diagnostic procedures. The severity of the disease course may lead to the consideration of a more aggressive treatment strategy.