Background The aim of this cross-sectional study was to assess risk factors for bleeding in immune thrombocytopenia (ITP) adults, including the determination of platelet count thresholds. Methods We selected all newly diagnosed ITP adults included in the Cytopénies Auto-immunes Registre Midi-PyrénéEN (CARMEN) register and at the French referral center for autoimmune cytopenias. The frequencies of any bleeding, mucosal bleeding and severe bleeding (gastrointestinal, intracranial, or macroscopic hematuria) at ITP onset were assessed. Platelet count thresholds were assessed by the use of receiver operating characteristic curves. All potential risk factors were included in logistic regression models. Results Among the 302 patients, the frequencies of any, mucosal and severe bleeding were 57.9%, 30.1%, and 6.6%, respectively. The best discriminant threshold of platelet count for any bleeding was 20 × 10 L . In multivariate analysis, factors associated with any bleeding were platelet count (< 10 × 10 L versus ≥ 20 × 10 L , odds ratio [OR] 48.2, 95% confidence interval [CI] 20.0-116.3; between 10 × 10 L and 19 × 10 L versus ≥ 20 × 10 L , OR 5.2, 95% CI 2.3-11.6), female sex (OR 2.6, 95% CI 1.3-5.0), and exposure to non-steroidal anti-inflammatory drugs (NSAIDs) (OR 4.8, 95% CI 1.1-20.7). A low platelet count was also the main risk factor for mucosal bleeding. Exposure to anticoagulant drugs was associated with severe bleeding (OR 4.3, 95% CI 1.3-14.1). Conclusions Platelet counts of < 20 × 10 L and < 10 × 10 L were thresholds for major increased risks of any and mucosal bleeding. Platelet count, female sex and exposure to NSAIDs should be considered for assessment of the risk of any bleeding. Exposure to anticoagulant drugs was a major risk factor for severe bleeding.

Patients with Doublecortin (DCX) mutations have severe cortical malformations associated with mental retardation and epilepsy. Dcx knockout (KO) mice show no major isocortical abnormalities, but have discrete hippocampal defects. We questioned the functional consequences of these defects and report here that Dcx KO mice are hyperactive and exhibit spontaneous convulsive seizures. Changes in neuropeptide Y and calbindin expression, consistent with seizure occurrence, were detected in a large proportion of KO animals, and convulsants, including kainate and pentylenetetrazole, also induced seizures more readily in KO mice. We show that the dysplastic CA3 region in KO hippocampal slices generates sharp wave-like activities and possesses a lower threshold for epileptiform events. Video-EEG monitoring also demonstrated that spontaneous seizures were initiated in the hippocampus. Similarly, seizures in human patients mutated for DCX can show a primary involvement of the temporal lobe. In conclusion, seizures in Dcx KO mice are likely to be due to abnormal synaptic transmission involving heterotopic cells in the hippocampus and these mice may therefore provide a useful model to further study how lamination defects underlie the genesis of epileptiform activities.

The clinical epidemiology of immune thrombocytopenia (ITP) is not well known in adults. This study was aimed at assessing the clinical epidemiology of incident ITP adults, the factors associated with chronicity and exposure to treatments. This study was conducted in the CARMEN registry, a multicentric prospective cohort aimed at including all newly diagnosed ITP adults in the French Midi-Pyrénées region, South of France (3 million inhabitants) from June 2013. Descriptive analyses and multivariate logistic regression models were conducted. Out of 121 newly diagnosed ITP until December 2014, 113 patients were followed in the region and gave informed consent. Median age was 65 years. Half of the patients were female, 20.3% had a secondary ITP, 50.4% had a Charlson's score ≥1, median platelet count was 17 × 10 /L; 50.9% had bleeding symptoms, including 2 severe gastrointestinal tract and 1 intracranial bleedings; 21.4% had another autoimmune disease and 20.3% experienced an infection within the six weeks before ITP onset. Persistency and chronicity rates were 68.2% and 58.7%, respectively. Antinuclear antibodies were associated with chronicity (OR: 2.89, 95% CI: 1.08-7.74). Sixty-eight (60.2%) patients were treated during the week following the diagnosis. Factors associated with the use of intravenous corticosteroids were secondary ITP and high bleeding score. Those associated with the use of intravenous immunoglobulin (IVIg) were a high bleeding score and low platelet count. In conclusion, severe bleeding is rare at ITP onset. Associated autoimmune diseases and recent infections were frequent. Antinuclear antibodies seem predictors of chronicity. Intravenous corticosteroids and IVIg were frequently used.

Mutations in the human X-linked doublecortin gene (DCX) cause major neocortical disorganization associated with severe intellectual disability and intractable epilepsy. Although Dcx knockout (KO) mice exhibit normal isocortical development and architecture, they show lamination defects of the hippocampal pyramidal cell layer largely restricted to the CA3 region. Dcx-KO mice also exhibit interneuron abnormalities. As well as the interest of testing their general neurocognitive profile, Dcx-KO mice also provide a relatively unique model to assess the effects of a disorganized CA3 region on learning and memory. Based on its prominent anatomical and physiological features, the CA3 region is believed to contribute to rapid encoding of novel information, formation and storage of arbitrary associations, novelty detection, and short-term memory. We report here that Dcx-KO adult males exhibit remarkably preserved hippocampal- and CA3-dependant cognitive processes using a large battery of classical hippocampus related tests such as the Barnes maze, contextual fear conditioning, paired associate learning and object recognition. In addition, we show that hippocampal adult neurogenesis, in terms of proliferation, survival and differentiation of granule cells, is also remarkably preserved in Dcx-KO mice. In contrast, following social deprivation, Dcx-KO mice exhibit impaired social interaction and reduced aggressive behaviors. In addition, Dcx-KO mice show reduced behavioral lateralization. The Dcx-KO model thus reinforces the association of neuropsychiatric behavioral impairments with mouse models of intellectual disability.