Screening for frailty in community-dwelling elderly subjects: Predictive validity of the modified SEGA instrument

International audienc

Trends in hospitalization rates for psoriasis flares since the introduction of biologics: a time series in France between 2005 and 2015

International audienc

Long-term follow-up after ileorectal anastomosis in ulcerative colitis (UC) identified factors associated with rectal outcome: a multicentre retrospective cohort of 343 patients from the GETAID/GETAID Surgery

Abstracts of the 11th Congress of ECCO - European Crohn’s and Colitis OrganisationInternational audienc

Individual red blood cell fetal hemoglobin quantification allows to determine protective thresholds in sickle cell disease

International audiencePolymerization of the sickle hemoglobin (HbS) is a key determinant of sickle cell disease (SCD), an inherited blood disorder. Fetal hemoglobin (HbF) is a major modulator of the disease severity by both decreasing HbS intracellular concentration and inhibiting its polymerization. However, heterocellular distribution of HbF is common in SCD. For HbS polymerization inhibition, the hypothesis of an "HbF per red blood cell (HbF/RBC) threshold" requires accurate measurement of HbF in individual RBC. To date, HbF detection methods are limited to a qualitative measurement of RBC populations containing HbF - the F cells, which are variable. We developed an accurate method for HbF quantification in individual RBC. A linear association between mean HbF content and mean RBC fluorescence by flow cytometry, using an anti-Human-HbF antibody, was obtained from non-SCD subjects presenting homogeneous HbF distribution. This correlation was then used to measure HbF/RBC. Hydroxyurea (HU) improves SCD clinical manifestations, mainly through its ability to induce HbF synthesis. The HbF distribution was analyzed in 14 SCD patients before and during HU treatment. A significant decrease in RBC population containing less than 2 pg of HbF/RBC was observed. Therefore, we tested associations for %RBC above different HbF/RBC thresholds and showed a decrease in the pathognomonic vaso-occlusive crisis incidence from the threshold of 4 pg. This quantity was also correlated with the level of sickle RBC after in vitro deoxygenation. This new method allows the comparison of HbF/RBC distributions and could be a useful tool to characterize baseline patients HbF distribution and therapeutic response to HbF inducers