[Immune thrombocytopenia: From pathogenesis to treatment]. / Thrombopénie immunologique : de la physiopathologie aux traitements.

Immune thrombocytopenia (ITP) is a rare autoimmune disease due to an immune peripheral destruction of platelets and an inappropriate platelet production. The pathogenesis of ITP is now better understood: it involves a humoral immune response which dependents on the stimulation of B cells by specific T cells called T follicular helper cells, leading to their differentiation into plasma cells that produce antiplatelet antibodies thus promoting the phagocytosis of platelets mainly by splenic macrophages. The deciphering of ITP pathogenesis has led to a better understanding of the inefficiency of treatments such as rituximab, although it has not provided yet the determination of biological predictive factor of response to treatments. Moreover, new therapeutic perspectives have been opened in the last few years with the development of molecules targeting Fcγ receptor signalling such as Syk inhibitor, or molecules increasing the clearance of pathogenic autoantibodies such as inhibitors of the neonatal Fc receptor (FcRn).

[Management of multirefractory immune thrombocytopenia]. / Prise en charge du purpura thrombopénique immunologique multiréfractaire.

Multirefractory immune thrombocytopenia (ITP) is defined by the absence of response to TPO receptor agonists, rituximab and splenectomy (or contraindicated or refused) and the need of treatment. The approach to multirefractory ITP must be systematic and firstly involves reconsidering the diagnosis. Inherited thrombocytopenia, lymphoid hemopathies and myelodysplastic syndrome are the main causes to be mentioned. Multirefractory ITP is often associated with secondary ITP with signs of clinical or biological autoimmunity, monoclonal gammopathy of undetermined significance and a poor response to corticosteroids. Therapeutic management is complex and is based on the combination of treatments. New treatments are being developed.

Rituximab and immune thrombocytopenia in adults: The state of knowledge 20 years later.

Rituximab has been used for immune thrombocytopenia (ITP) for almost 20 years and is now considered a valid off-label second-line treatment. About 60% to 70% of patients with ITP show initial response to rituximab, but in half of these patients, the disease will eventually relapse. Therefore, in 30% of patients with persistent or chronic ITP, one course of rituximab at 375 mg/m2/week for 4 weeks or 2 fixed 1000-mg rituximab infusions allows for a sustained response rate at 5 years. Unfortunately, to date, no robust predictor of long-term sustained response has been found to assist the physician in deciding to treat with rituximab on an individual basis, and the choice of rituximab or another second-line treatment must be individualized and shared with the patient. Retreatment with rituximab has been found efficient, with a similar or higher magnitude and duration of response in most patients. Rituximab is usually well tolerated, with mainly mild and easily manageable infusion-related adverse events. Severe infections are uncommon, including in the long-term, and occur in patients with at least another contributing factor in more than two thirds. Several issues remain to be resolved. Indeed, head-to-head comparisons with other and new treatments in ITP and robust predictors of long-term response are urgently needed to better determine the position of rituximab in the therapeutic armamentarium for adult ITP. Additionally, the place of combination therapies, maintenance therapy with rituximab and rituximab in newly-diagnosed ITP deserve additional studies.

[Hemophagocytic lymphohistiocytosis with granulomatosis and diffuse T-cell infiltration associated with disseminated Nocardiosis and pulmonary infection due to Streptomyces spp]. / Syndrome d'activation macrophagique associé à une granulomatose et une infiltration lymphocytaire T CD4 diffuse révélant une nocardiose disséminée et une infection pulmonaire à Streptomyces spp.

INTRODUCTION: Hemophagocytic lymphohistiocytosis (HLH) is a rare syndrome frequently secondary to infectious disease, especially in immuno-compromised patients. We report a HLH secondary to disseminated nocardiosis and Streptomyces spp pulmonary infection. CASE REPORT: A 69-years-old women had recent subcutaneous nodules of the forearms and loins associated with peripheral neuropathy and pulmonary nodule of the right upper lobe. Cutaneous biopsy revealed granuloma. Cutaneous lesions worsened and the patient developed a HLH with probable cardiac and neurological involvement, associated with cutaneous granulomatosis and diffuse polyclonal lymphocyte proliferation. Nocardia PCR was positive in cutaneous biopsy. Pulmonary samples revealed Streptomyces in culture and Nocardia in PCR. The evolution under antibiotic treatment was favorable. CONCLUSION: Recent diagnosis of HLH without obvious etiology should lead to etiological investigation, including the search for infections with slow-growing bacteria such as Nocardia or Streptomyces spp.

Risk factors for bleeding, including platelet count threshold, in newly diagnosed immune thrombocytopenia adults.

Essentials Risk factors of bleeding in adult immune thrombocytopenia are not known. This multicenter study assessed risk factors of bleeding at immune thrombocytopenia onset. Platelet count thresholds associated with bleeding were < 20 × 109 L-1 and < 10 × 109 L-1 . Exposure to anticoagulants was a major risk factor of severe bleeding. SUMMARY: 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 × 109 L-1 . In multivariate analysis, factors associated with any bleeding were platelet count (< 10 × 109 L-1 versus ≥ 20 × 109 L-1 , odds ratio [OR] 48.2, 95% confidence interval [CI] 20.0-116.3; between 10 × 109 L-1 and 19 × 109 L-1 versus ≥ 20 × 109 L-1 , 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 × 109 L-1 and < 10 × 109 L-1 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.

[Thrombosis during thrombopoietin receptor agonist treatment for immune thrombocytopenia. A French multicentric observational study]. / Thromboses sous agonistes du récepteur de la thrombopoïétine au cours du purpura thrombopénique immunologique. Étude rétrospective multicentrique en France.

INTRODUCTION: Thrombopoietin-receptor agonists (TPO-RA) are marketed for immune thrombocytopenia (ITP). They have been associated to thrombosis occurrence in randomized controlled trials. However, the characteristics of these thromboses in the real-life practice as well as their management are poorly known. The objectives of this study were to determine the risk factors, circumstances and management of thrombosis occurring during exposure to TPO-RA in ITP. METHODS: We carried out a multicentre retrospective study in France. Moreover, all cases reported to the French pharmacovigilance system were also analyzed. RESULTS: Overall, 41 thrombosis (13 arterial) in 36 ITP patients (14 males and 22 females, mean age: 59 years) were recorded between January 2009 and October 2015. Twenty patients were treated with romiplostim, 15 with eltrombopag and 1 was treated by both medications. Thirty-three (92%) of the patients had another risk factor for thrombosis. Ten (28%) had an history of thrombosis and 13 (36%) received immunoglobulin in the month preceding the thrombotic event. Three had antiphospholipid antibodies; congenital low-risk thrombophilia was found in 4 cases; 18 patients (50%) were splenectomized. Median platelet count at the time of thrombosis was 172G/l (1-1049G/l). In 22 patients (56%), a good prognosis was associated with the thrombosis and was not linked with TPO-RA withdrawal. Bleeding events occurred in 14% of the patients treated with antiplatelet or anticoagulant drug, including 5% serious events (1 death of intracranial haemorrhage, 1 death of haemorrhagic shock). CONCLUSIONS: The thrombotic risk may be carefully assessed before starting TPO-RA in ITP patients. The impact of antiphospholipid antibodies and of congenital thrombophilia remains to be defined. Thrombosis evolution seems independent of TPO-RA management. Bleeding manifestations seem rare. Poor prognosis was mainly due to ischemic sequelae.

NK cell compartment in the peripheral blood and spleen in adult patients with primary immune thrombocytopenia.

Immune thrombocytopenic purpura (ITP) is a disease characterized by antibody-mediated platelet destruction. The T- and B-cell subsets have been extensively studied in primary ITP, but the NK cell compartment has been less thoroughly explored. We investigated the NK cell receptor repertoire and the functionality of NK cells in the peripheral blood and spleen in patients with primary ITP. An immunophenotypic analysis of peripheral blood lymphocytes from patients revealed that the numbers of CD19+ B lymphocytes, CD4+ and CD8+ T lymphocytes and CD3-CD56+ NK cells were within the normal range. No major alteration to the expression of distinct inhibitory or activating NK cell receptors was observed. The functionality of NK cells, as evaluated by their ability to degranulate in conditions of natural cytotoxicity or antibody-dependent cell cytotoxicity (ADCC), was preserved in these patients. By contrast, these stimuli induced lower levels of IFNγ production by the NK cells of ITP patients than by those of healthy controls. We then compared the splenic NK cell functions of ITP patients with those of cadaveric heart-beating donors (CHBD) as controls. The splenic NK cells of ITP patients tended to be less efficient in natural cytotoxicity conditions and more efficient in ADCC conditions than control splenic NK cells. Finally, we found that infusions of intravenous immunoglobulin led to the inhibition of NK cell activation through the modulation of the interface between target cells and NK cells.

The use of rituximab to prevent severe delayed haemolytic transfusion reaction in immunized patients with sickle cell disease.

BACKGROUND: Delayed haemolytic transfusion reaction (DHTR) is mainly caused by an immune response to transfused red blood cells (RBCs). Immunized patients have a high risk of producing antibodies in response to further transfusion. Controlling the immune response to RBCs is therefore a major goal in sickle cell disease (SCD). STUDY DESIGN: We report an observational study of eight alloimmunized SCD patients with history of severe DHTR who were treated with rituximab before a new transfusion to prevent further immunization and DHTR. RESULTS: Five patients showed a good clinical outcome following transfusion preceded by preemptive treatment with rituximab. The remaining patients presented mild DHTR. In all patients, the results of post-transfusion screening tests were identical to those of pretransfusion tests; no newly formed antibodies were detected. CONCLUSION: These cases suggest that rituximab prevents at least occurrence of newly formed antibodies in high responders and minimizes the risk of severe DHTR. This study confirms that DHTR is complex in SCD and does not rely only on the classical antigens/antibodies conflict. Considering potentially serious adverse effect of rituximab, this treatment should be considered cautiously, and only when transfusion is absolutely necessary in patients with history of severe DHTR linked to immunization.

[Post-splenectomy complications in primary immune thrombocytopenia. Literature review and preventive measures]. / Complications de la splénectomie au cours du purpura thrombopénique immunologique. Revue de la littérature et mesures de prévention.

Management of primary immune thrombocytopenia (ITP) has changed, and clinical practice broadens the use of thrombopoietin receptor agonists and anti-CD20 antibody as options for second-line therapy, as alternative to splenectomy. Splenectomy remains a successful, definitive curative treatment. The purpose of this review about the complications of the splenectomy, in the context of ITP, is to increase the awareness of clinicians towards the preventive measures, which are often not correctly applied.

[Haematopoietic stem cell transplantation in the treatment of autoimmune diseases]. / Intensification thérapeutique dans les maladies auto-immunes.

PURPOSE: During the past ten years, more than 1000 patients suffering from severe autoimmune disease have received an autologous haematopoietic stem cell transplant. These new therapeutic have been used in systemic sclerosis (scleroderma), multiple sclerosis, rheumatoid arthritis, juvenile idiopathic arthritis and systemic lupus erythematosus. CURRENT KNOWLEDGE AND KEY POINTS: Autologous haematopoietic stem cell transplantation has become a curative option for condition with very poor prognosis as severe systemic sclerosis, lupus erythematosus or other systemic diseases. This review summarizes the current experience in the phase I and II clinical trials in Europe and North America. We describe the main results and the limits of stem cell transplantation in systemic diseases. FUTURE PROSPECTS AND PROJECTS: Autologous haematopoietic stem cell transplant in the treatment of autoimmune disease has evolved from a experimental concept to a clinically feasible and powerful therapy for selected patients with severe disease.

[Aetiological spectrum of hyperferritinemia]. / Spectre étiologique des hyperferritinémies.

UNLABELLED: Serum ferritin levels may be increased in many conditions: renal diseases, liver diseases, human immunodeficiency virus infection. The purpose of this study was to assess the aetiological spectrum of high serum ferritin levels in a 1200-bed university hospital, to compare our results with the data already published and to assess a potential association between aetiology and ferritin levels. PATIENTS AND METHODS: Patients with a serum ferritin level higher than 600 microg/l were retrospectively included between 15 November 2003 and 15 January 2004, and their medical records were reviewed. RESULTS: Ninety-eight patients (38 women and 60 men; median age: 59,5 years [19-92]) were recruited in departments of hepatology and gastroenterology (22%), haematology (14%) and internal medicine (18%). Diagnosis performed were: non-HIV systemic infections (23,8%), haematological diseases (16,1%), alcoholism (11,2%) and malignancies (9,8%). Dialysed chronic renal failure, liver diseases, haemochromatosis and systemic inflammatory diseases counted for 4.2 to 5.2% of cases. Serum ferritin level lied between 600 and 1000 microg/l for 50 patients, between 1000 and 1500 microg/l for 24, and over 1500 microg/l for 24. There was no significant difference between the three groups as regards the etiological distribution. DISCUSSION: In our study, chronic renal failure was not a major cause of high ferritin level: this is probably due to the current use of erythropoietin, which has decreased the use of blood transfusions. The two major aetiology of hyperferritinemia were non-HIV infections and malignancies.

[Muscular haematoma in Henoch-Schönlein purpura]. / Hématome intramusculaire sévère au cours du purpura rhumatoïde.

INTRODUCTION: Henoch-Schonlein purpura is one of the most frequent systemic vasculitis in children. In adults, muscle involvement is extremely rare and not very well characterized. We report a case of Henoch-Schonlein purpura with severe skin and renal involvement in witch multiple intramuscular haematoma leaded to severe anaemia. Histological examination confirms the muscle localization of the disease. EXEGESIS: A 68 years old man treated by oral anticoagulation for multiple venous thrombosis, was admitted with necrotic vasculitis of the skin, abdominal pain and segmental IgA glomerulopathy. The diagnosis of Henoch-Schonlein purpura was rapidly made and intensive steroid therapy started. After rapid improvement, a haemorrhagic shock due to voluminous intramuscular haematoma was diagnosed by MRI. Histological examination of the muscle, confirms the localization of the disease. CONCLUSION: Intramuscular haematomas are very uncommon in Henoch-Schonlein purpura. There are usually a consequence of muscular immune complex vasculitis. In our patient, high dose corticosteroid was not unable to control the disease.