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Featured researches published by M. Hamidou.


Medicine | 2012

Igg4-related Systemic Disease: Features and Treatment Response in a French Cohort

M. Ebbo; Laurent Daniel; M. Pavic; P. Sève; M. Hamidou; Emmanuel Andres; S. Burtey; L. Chiche; Jacques Serratrice; Maïté Longy-Boursier; M. Ruivard; Julien Haroche; Bertrand Godeau; Anne-Bérengère Beucher; Jean-Marie Berthelot; Thomas Papo; Jean-Loup Pennaforte; A. Benyamine; Noémie Jourde; Cédric Landron; P. Roblot; Olivier Moranne; Christine Silvain; Brigitte Granel; Fanny Bernard; V. Veit; K. Mazodier; E. Bernit; Hugues Rousset; José Boucraut

AbstractIgG4-related systemic disease is now recognized as a systemic disease that may affect various organs. The diagnosis is usually made in patients who present with elevated IgG4 in serum and tissue infiltration of diseased organs by numerous IgG4+ plasma cells, in the absence of validated diagnosis criteria. We report the clinical, laboratory, and histologic characteristics of 25 patients from a French nationwide cohort. We also report the treatment outcome and show that despite the efficacy of corticosteroids, a second-line treatment is frequently necessary. The clinical findings in our patients are not different from the results of previous reports from Eastern countries. Our laboratory and histologic findings, however, suggest, at least in some patients, a more broad polyclonal B cell activation than the skewed IgG4 switch previously reported. These observations strongly suggest the implication of a T-cell dependent B-cell polyclonal activation in IgG4-related systemic disease, probably at least in part under the control of T helper follicular cells.


Autoimmunity Reviews | 2014

Long-term effectiveness and safety of interleukin-1 receptor antagonist (anakinra) in Schnitzler's syndrome: A french multicenter study

Antoine Néel; Benoit Henry; S. Barbarot; Agathe Masseau; François Perrin; C. Bernier; Xavier Kyndt; Xavier Puéchal; P.J. Weiller; O. Decaux; J. Ninet; Arnaud Hot; Achille Aouba; L. Astudillo; Jean-Marie Berthelot; Fabrice Bonnet; Jean-Marie Brisseau; B. Cador; Fabienne Closs-Prophette; Thomas Dejoie; Jean-Dominique De Korwin; Robin Dhote; Renato Fior; B. Grosbois; E. Hachulla; Pierre-Yves Hatron; Henry Jardel; David Launay; Adrien Lorleac'H; P. Pottier

The aim of this study is to assess the long-term effectiveness and safety of IL1Ra in Schnitzler syndrome (SchS). Between 2010 and 2012, we performed a nationwide survey among French internal medicine departments to identify SchS patients. We retrospectively analyzed the long-term efficacy and safety of IL1Ra and the outcome of patients that did not receive this treatment. Forty-two patients were included in the study, 29 of whom received IL1Ra. The mean age at disease onset was 59.9years. Disease manifestations included urticaria (100%), fever (76%), bone/joint pain (86%), bone lesions (76%), anemia (67%), and weight loss (60%). The monoclonal gammopathy was overwhelmingly IgM kappa (83%). The mean follow-up was 9.5years (range: 1.6-35). Two patients developed Waldenströms macroglobulinemia and one developed AA amyloidosis. All of the 29 patients who received IL1Ra responded dramatically. After a median follow-up of 36months (range: 2-79), the effectiveness remained unchanged. All patients remained on anti-IL-1 therapy. Twenty-four patients (83%) went into complete remission and five (17%) into partial remission. Three patients experienced grade 3-4 neutropenia. Six patients developed severe infections. No lymphoproliferative diseases occurred while on IL1Ra. When last seen, all patients without anakinra had an active disease with variable impact on their quality of life. Their median corticosteroids dosage was 6mg/d (range: 5-25). IL1Ra is effective in SchS, with a sharp corticosteroid-sparing effect. Treatment failures should lead to reconsider the diagnosis. Long-term follow-up revealed no loss of effectiveness and a favorable tolerance profile. The long-term effects on the risk of hemopathy remain unknown.


PLOS ONE | 2011

Decreased numbers of blood dendritic cells and defective function of regulatory T cells in antineutrophil cytoplasmic antibody-associated vasculitis.

Marie Rimbert; M. Hamidou; Cécile Braudeau; Xavier Puéchal; Luis Teixeira; Hélène Caillon; A. Néel; Marie Audrain; Loïc Guillevin; Régis Josien

Background Dendritic cells (DC) and regulatory cells (Treg) play pivotal roles in controlling both normal and autoimmune adaptive immune responses. DC are the main antigen-presenting cells to T cells, and they also control Treg functions. In this study, we examined the frequency and phenotype of DC subsets, and the frequency and function of Treg from patients with ANCA-associated vasculitis (AAV). Methodology/Principal Findings Blood samples from 19 untreated patients with AAV during flares and before any immunosuppressive treatment were analyzed, along with 15 AAV patients in remission and 18 age-matched healthy controls. DC and Treg numbers, and phenotypes were assessed by flow cytometry, and in vitro suppressive function of Treg was determined by co-culture assay. When compared to healthy volunteers, absolute numbers of conventional and plasmacytoid DC were decreased in AAV patients. During the acute phase this decrease was significantly more pronounced and was associated with an increased DC expression of CD62L. Absolute numbers of Treg (CD4+CD25highCD127low/− Tcells) were moderately decreased in patients. FOXP3 and CD39 were expressed at similar levels on Treg from patients as compared to controls. The suppressive function of Treg from AAV patients was dramatically decreased as compared to controls, and this defect was more pronounced during flares than remission. This Treg functional deficiency occurred in the absence of obvious Th17 deviation. Conclusion In conclusion, these data show that AAV flares are associated with both a decrease number and altered phenotype of circulating DC and point to a role for Treg functional deficiency in the pathogenesis of AAV.


Journal of The American Society of Nephrology | 2012

Elevated Soluble Flt1 Inhibits Endothelial Repair in PR3-ANCA–Associated Vasculitis

Sandrine Le Roux; Ruth J. Pepper; Alexandre Dufay; Mélanie Néel; Emmanuelle Meffray; Noël Lamandé; Marie Rimbert; Régis Josien; M. Hamidou; Maryvonne Hourmant; H. Terence Cook; Béatrice Charreau; Etienne Larger; Alan D. Salama; Fadi Fakhouri

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis exhibits endothelial damage, but the capacity for vessel repair in this disorder is not well understood. Here, we observed a marked increase in serum levels of soluble Flt1 (sFlt1), a potent inhibitor of vascular endothelial growth factor, in patients with active ANCA-associated vasculitis compared with patients during remission and other controls. Serum levels of sFlt1 correlated with C5a, an anaphylatoxin released after complement activation. Serum from patients with acute ANCA-associated vasculitis disrupted blood flow in the chicken chorioallantoic membrane assay, suggesting an antiangiogenic effect. Preincubation with excess human vascular endothelial growth factor prevented this effect. Anti-proteinase-3 (PR3) mAb and serum containing PR3-ANCA from patients with active vasculitis both induced a significant and sustained release of sFlt1 from monocytes, whereas anti-myeloperoxidase (MPO) mAb or polyclonal antibodies did not. However, the serum containing polyclonal PR3-ANCA did not induce release of sFlt1 from cultured human umbilical vein endothelial cells. In summary, these data suggest that anti-PR3 antibodies, and to a much lesser extent anti-MPO antibodies, increase sFlt1 during acute ANCA-associated vasculitis, leading to an antiangiogenic state that hinders endothelial repair.


American Journal of Kidney Diseases | 1995

Captopril and aspirin in treatment of renal microangiopathy in primary antiphospholipid syndrome

M. Hamidou; Anne Moreau; Patrick Jego; Angelo Testa; Firouze Bani-Sadr; Francoise Buzelin; J.Y. Grolleau

Treatment of antiphospholipid syndrome (APS) is controversial. We report a case of renal microangiopathy in a 40-year-old woman with APS. The nephropathy was isolated without signs of disseminated thrombotic microangiopathy or progressive systemic sclerosis. Similarities with sclerodermatous kidney and an increase in plasma renin activity led us to initiate treatment with aspirin and captopril, with excellent control of the renal syndrome. We believe this therapeutic regimen may be an effective means of treating the renal microangiopathy of APS.


Frontiers in Immunology | 2017

T Cell Polarization toward TH2/TFH2 and TH17/TFH17 in Patients with IgG4-Related Disease

A. Grados; M. Ebbo; Christelle Piperoglou; Matthieu Groh; Alexis Régent; M. Samson; Benjamin Terrier; Anderson Loundou; Nathalie Morel; S. Audia; F. Maurier; J. Graveleau; M. Hamidou; Amandine Forestier; S. Palat; E. Bernit; Bernard Bonotte; Catherine Farnarier; J.-R. Harle; Nathalie Costedoat-Chalumeau; Frédéric Vély; N. Schleinitz

IgG4-related disease (IgG4-RD) is a fibro-inflammatory disorder involving virtually every organ with a risk of organ dysfunction. Despite recent studies regarding B cell and T cell compartments, the disease’s pathophysiology remains poorly understood. We examined and characterized subsets of circulating lymphocytes in untreated patients with active IgG4-RD. Twenty-eight consecutive patients with biopsy-proven IgG4-RD were included in a prospective, multicentric study. Lymphocytes’ subsets were analyzed by flow cytometry, with analysis of TH1/TH2/TH17, TFH cells, and cytokine release by peripheral blood mononuclear cells. Results were compared to healthy controls and to patients with primary Sjögren’s syndrome. Patients with IgG4-RD showed an increase of circulating T regulatory, TH2, TH17, and CD4+CXCR5+PD1+ TFH cell subsets. Accordingly, increased levels of IL-10 and IL-4 were measured in IgG-RD patients. TFH increase was characterized by the specific expansion of TFH2 (CCR6−CXCR3−), and to a lesser extent of TFH17 (CCR6+CXCR3−) cells. Interestingly, CD4+CXCR5+PD1+ TFH cells normalized under treatment. IgG4-RD is characterized by a shift of circulating T cells toward a TH2/TFH2 and TH17/TFH17 polarization. This immunological imbalance might be implicated in the disease’s pathophysiology. Treatment regimens targeting such T cells warrant further evaluation.


Blood Cells Molecules and Diseases | 2013

Altered innate function of plasmacytoid dendritic cells restored by enzyme replacement therapy in Gaucher disease.

Cécile Braudeau; J. Graveleau; Marie Rimbert; Antoine Néel; M. Hamidou; Bernard Grosbois; Audrey Besançon; Stéphanie Giraudet; Caroline Terrien; Régis Josien; Agathe Masseau

BACKGROUND Gaucher disease (GD) is caused by an autosomal-recessive deficiency of β-glucocerebrosidase leading to an accumulation of glucosylceramide in monocytes/macrophage lineage. We analyzed immune cells and especially the function of dendritic cells to evaluate the potential impact of glucosylceramide accumulation in these cells and its possible role in infections and malignancies usually described in this pathology. These analyses were performed for each patient without and under enzyme replacement therapy. METHODS Seven GD patients were studied and compared with healthy volunteers. Immune cells (B cells, T cells, NK, dendritic cells), were analyzed by flow cytometry directly on whole blood. Cytokine production by blood dendritic cells was assessed after stimulation by toll-like receptor ligands. Cytokines in sera were measured using a multiplex assay. RESULTS GD patients displayed decreased numbers of NK cells, γδ2 T cells and increased frequency of memory CD4(+)CD45RO(+) T cells, when compared to healthy controls. Numbers of dendritic cells (myeloid (mDC) and plasmacytoid (pDC) dendritic cells) were also decreased. We demonstrated that pDC from GD patients exhibited a decrease in IFNα production after TLR9 stimulation compared to controls. Importantly, enzyme replacement therapy restored pDC function. Finally, we observed an increase of IL-8 and IL-18 in GD patient sera, which were reduced under enzyme replacement therapy. CONCLUSIONS Our data confirm that patients with GD exhibit altered numbers of innate and T lymphocytes and show for the first time that pDC from GD patients exhibit altered responsiveness to TLR9. These alterations could contribute to a decreased response to pathogens and could favor the development of malignancies.


Leukemia Research | 2016

Autoimmune and inflammatory diseases associated with chronic myelomonocytic leukemia: A series of 26 cases and literature review

Eric Grignano; A. Mekinian; Thorsten Braun; E. Liozon; M. Hamidou; Olivier Decaux; Xavier Puéchal; Jean Emmanuel Kahn; Yoland Schoindre; Julien Rossignol; Olivier Lortholary; Bertrand Lioger; Olivier Hermine; Sophie Park; Lionel Ades; Francois Montestruc; Laure Ricard; Claude Gardin; Pierre Fenaux; Olivier Fain

We wanted to describe the characteristics, treatment and outcome of autoimmune and inflammatory diseases (SAIDs) associated with chronic myelomonocytic leukemia (CMML), and conducted a French multicenter retrospective study and a literature review. We included 26 cases of CMML (median age 75 years, 54% female), 80% with CMML-1. CPSS score was low (0 or 1) in 75% of cases. SAIDS was systemic vasculitis in 54%. Diagnosis of the 2 diseases was concomitant in 31% cases, and CMML was diagnosed before SAIDs in 12 cases (46%). First line treatment for SAIDs consisted mostly of steroid, with 85% of response. Second-line treatment was needed in 40% cases. Six patients received hypomethylating agents, with 66% response on SAIDs. A literature review found 49 cases of CMML-associated SAIDs, in whom SAIDs was systemic vasculitis in 29% cases. Hence, vasculitis is the most frequent SAIDs associated with CMML. After initial response to steroids, recurrence and steroid-dependence were frequent. Hypomethylating agents may be interesting in this context.


Revue de Médecine Interne | 2010

Manifestations cardiaques au cours la granulomatose de Wegener: à propos de quatre observations et revue de la littérature

Gabrielle Sarlon; C. Durant; Y. Grandgeorge; E. Bernit; V. Veit; M. Hamidou; N. Schleinitz; J.-R. Harle

INTRODUCTION Discordance exists between the results of post-mortem studies and the low number of clinical reported cases of cardiac involvements in Wegeners granulomatosis. CASE REPORTS Data from four patients were studied retrospectively. Three patients had associated airway localization and three had kidney involvement. All patients had positive test for anti-PR3 antineutrophil antibodies. Two patients presented with dilated cardiomyopathy (one with terminal cardiac failure), another patient with complete atrioventricular block and pericarditis, and the remaining one with myopericarditis. One patient was asymptomatic. For three of these patients, the cardiac manifestations were contemporary of the diagnosis of Wegeners granulomatosis and had a severe disease course. CONCLUSION Cardiac events in Wegeners granulomatosis are probably underestimated, given the various type of heart damage and the clinical presentation. Cardiac involvement seems to be associated with a poor prognosis. Thus, we recommend systematic and regular cardiac assessment in the follow-up of patients with Wegeners granulomatosis.


Autoimmunity Reviews | 2015

Venous thromboembolism related to warm autoimmune hemolytic anemia: A case–control study

M. Lecouffe-Desprets; Antoine Néel; J. Graveleau; C. Leux; François Perrin; B. Visomblain; M. Artifoni; Agathe Masseau; Jerome Connault; P. Pottier; Christian Agard; M. Hamidou

BACKGROUND The risk of venous thromboembolism (VTE) during warm autoimmune hemolytic anemia (wAIHA) is apparent in several published series. Unlike proximate disorders (autoimmune thrombocytopenia, non-immune hemolytic diseases) little is known about the presentation and risk factors for VTE in this setting. OBJECTIVE To determine the frequency, presentation and risk factors for VTE associated with wAIHA. METHODS We performed a single center retrospective study of adult patients (>18years) followed for wAIHA between 2009 and 2013. VTE risk factors were systematically assessed. The characteristics of patients with or without VTE were compared. VTE presentation and precipitating factors were analyzed. The Padua VTE risk score was calculated in each case. RESULTS Forty patients were included. wAIHA was idiopathic in 24 patients (60%). Twelve patients (30%) had Evans syndrome. Mean lowest hemoglobin level was 6.6g/dl [3.7-11.5]. Eight patients (20%) presented VTE after the appearance of wAIHA, at a mean age of 52.5years. All patients had pulmonary embolus, associated with a deep venous thrombosis in 4 cases. At the time of VTE 7/8 patients had frank hemolysis (median hemoglobin level: 7g/dL) and 6/8 were outpatients with a low Padua VTE risk score. The frequency of usual VTE risk factor was similar in cases and controls. By contrast, lowest hemoglobin level was significantly lower in patients that experienced VTE (5.3 vs 7.2g/dL, p=0.016). During the first episode of wAIHA, patients with concurrent VTE had a more pronounced anemia (5.3 vs 7.4g/dL, p=0.026). At the time of VTE, anemia was more severe when no other precipitating factor was present (6 vs 8.9g.dL, p=0.04). CONCLUSION In our cohort, 20% of patients with wAIHA presented VTE. The vast majority of VTE occurred during severe hemolytic flares and were not attributable to usual VTE risk factors. VTE prophylaxis is advisable in any patient admitted for wAIHA, irrespective of Padua VTE risk score. Prophylaxis also seems reasonable for outpatients with marked hemolysis.

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J.-R. Harle

Aix-Marseille University

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N. Schleinitz

Aix-Marseille University

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A. Néel

University of Nantes

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M. Ebbo

Aix-Marseille University

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Loïc Guillevin

Paris Descartes University

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A. Grados

Aix-Marseille University

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