F Leynadier

Unité Inserm U1077, Caen, Lower Normandy, France

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Publications (244)439.45 Total impact

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    ABSTRACT: Background. An in vitro basophil activation test, based on the detection of CD63 upregulation induced by NSAIDs, has been described. Its clinical significance remains controversial. Objectives. In patients with a history of nonallergic NSAID hypersensitivity, stratified according to the severity of the symptoms, to assess with NSAIDs the predictive value of basophil (BAT) and monocyte (MAT) activation tests. Patients/Methods. Sixty patients who had NSAIDs-induced or exacerbated urticaria/angiooedema and 20 controls was included. After incubation with NSAIDs or acetaminophen, leukocytes were analysed for CD63 upregulation. Results. With aspirin, the sensitivity (37%) and specificity (90%) of BAT agree with already published results. In contrast, when patients had had cutaneous and visceral reactions, the frequency of positive BAT 14/22 (64%, P < 0.001) or MAT 10/22 (46%, P < 0.01) were increased. Conclusions. Positive tests were more frequent among patients having a severe hypersensitivity contrasting with the other patients who had results similar to controls.
    Journal of Allergy 01/2012; 2012:580873.
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    ABSTRACT: Aspirin is one of the most widely prescribed drugs in the world on account of its analgesic, antipyretic, and anti-inflammatory properties. Its effect on platelet aggregation makes it the first choice for prophylaxis in cardiovascular, neurological and obstetric diseases. However, a history of aspirin-induced urticaria and/or angioedema is usually a contraindication for further prescription of the drug. The aim of this article was to demonstrate that patients presenting aspirin-induced cutaneous reactions at anti-inflammatory doses can safely benefit from aspirin reintroduction at platelet-inhibitory doses. Patients with a history of aspirin-induced urticaria and/or angioedema referred to our department between January 2000 and June 2008 for double-blind placebo-controlled reintroduction at platelet-inhibitory doses for a medical indication were enrolled in this study. Seventy patients with aspirin hypersensitivity as well as a medical indication for this therapy were referred to our department. Of these, 38 (54.3%) had a history of aspirin-induced urticaria and/or angioedema, including three laryngeal oedemas (7.9%). All subjects received platelet-inhibitory doses of aspirin (maximal total dose: 400mg/day) in double-blind placebo-controlled fashion during a one-day hospitalization period. None of the patients presented an immediate hypersensitivity reaction. Only one patient, who had received a cumulative dose of 200mg/day, reported diffuse urticaria and facial angioedema of no clinical significance the following day. He had a history of chronic urticaria. This article demonstrates the safety of reintroducing platelet-inhibitory doses of aspirin in patients in whom it is indicated and reporting aspirin-induced urticaria and/or angioedema with anti-inflammatory doses. However, patients with a history of chronic urticaria should undergo a challenge with the lowest platelet-inhibitory dose (75mg/day) in order to minimize the risk of aggravating their condition.
    Annales de Dermatologie et de Vénéréologie 02/2009; 136(1):15-20. · 0.60 Impact Factor
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    ABSTRACT: Background Aspirin is one of the most widely prescribed drugs in the world on account of its analgesic, antipyretic, and anti-inflammatory properties. Its effect on platelet aggregation makes it the first choice for prophylaxis in cardiovascular, neurological and obstetric diseases. However, a history of aspirin-induced urticaria and/or angioedema is usually a contraindication for further prescription of the drug. The aim of this article was to demonstrate that patients presenting aspirin-induced cutaneous reactions at anti-inflammatory doses can safely benefit from aspirin reintroduction at platelet-inhibitory doses. Patients and Methods Patients with a history of aspirin-induced urticaria and/or angioedema referred to our department between January 2000 and June 2008 for double-blind placebo-controlled reintroduction at platelet-inhibitory doses for a medical indication were enrolled in this study. Results Seventy patients with aspirin hypersensitivity as well as a medical indication for this therapy were referred to our department. Of these, 38 (54.3%) had a history of aspirin-induced urticaria and/or angioedema, including three laryngeal oedemas (7.9%). All subjects received platelet-inhibitory doses of aspirin (maximal total dose: 400 mg/day) in double-blind placebo-controlled fashion during a one-day hospitalization period. None of the patients presented an immediate hypersensitivity reaction. Only one patient, who had received a cumulative dose of 200 mg/day, reported diffuse urticaria and facial angioedema of no clinical significance the following day. He had a history of chronic urticaria. Conclusion This article demonstrates the safety of reintroducing platelet-inhibitory doses of aspirin in patients in whom it is indicated and reporting aspirin-induced urticaria and/or angioedema with anti-inflammatory doses. However, patients with a history of chronic urticaria should undergo a challenge with the lowest platelet-inhibitory dose (75 mg/day) in order to minimize the risk of aggravating their condition.
    Annales De Dermatologie Et De Venereologie - ANN DERMATOL VENEREOL. 01/2009; 136(1):15-20.
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    ABSTRACT: To confirm allergy to beta-lactam (BL), a basophil activation test in flow cytometry based on CD63 up-regulation was described. CD203c is a more recent basophil activation marker and up to day there is no consensus about which marker is the more sensitive one. CD203c has not yet been evaluated in the diagnosis of BL allergy. The aim of the study was to compare the reliability of CD203c to CD63 for the diagnosis of amoxicillin (AX) allergy, which is nowadays the most frequent BL allergy. Twenty-seven patients with an immediate positive skin test (ST) to AX, 20 had had anaphylaxis with AX and 7 had urticaria and/or angioedema, were compared with 14 controls with no allergy to BL and to six patients with delayed positive ST to AX. In the anaphylaxis group, AX induced up-regulation of CD203c in the basophils of 12 patients out of 20 (60%) and of CD63 in four patients (20%) (P<0.02). Two patients out of seven with urticaria or angioedema had a positive result with CD203c and CD63. In patients who had anaphylaxis, ampicillin (AMP) induced CD203c up-regulation in eight out of 12 (67%) patients tested, and CD63 up-regulation in 4 out of 12 (33%) (all patients who had anaphylaxis could not be tested with AMP). False-positive results were observed with CD203c as well as CD63, and for 10 patients indeed this was confirmed by a negative drug provocation test. The origin of conflicting results between CD63 and CD203c might be at least the targeting of basophils based on anti-IgE labelling. Among IgE(+) gated cells, by means of CD33, a marker of monocytes, a contamination up to 50% by monocytes was detected. In contrast to CD63, CD203c is an activation marker specific of basophils with a basal low-level expression in resting basophils. Thus, IgE and CD203c double targeting of basophils avoids the contamination by monocytes. CD203c seems to be a more sensitive activation marker of basophils than CD63 for the diagnosis of amoxicillin allergy.
    Clinical & Experimental Allergy 07/2008; 38(6):921-8. · 4.79 Impact Factor
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    ABSTRACT: Sublingual immunotherapy (SLIT) is accepted as a safe and effective route for the treatment of grass pollen allergy, but clarification of its clinical and biological efficacy requires more study. To evaluate the efficacy, safety, and compliance of SLIT with a standardized 3-grass pollen extract in patients with grass pollen seasonal allergic rhinoconjunctivitis, with or without mild asthma. This multicenter, randomized, double-blind study included 127 patients (aged 12-41 years; mean age, 24.9 years) with grass pollen seasonal allergic rhinoconjunctivitis, with or without mild asthma. They received either SLIT with a high-dose, standardized, 3-grass pollen extract or placebo for 10 months before and during the grass pollen season. The efficacy evaluation compared weekly clinical scores (defined as the sum of the symptom score and rescue medication score) to measure rhinoconjunctivitis and asthma for the first 8 weeks of the pollen season. We also evaluated safety and compliance and measured changes in anti-Dactylis specific IgG4 antibody levels. There was a trend in favor of the study group in the mean adjusted clinical score. The groups were not comparable on inclusion (P = .02): the SLIT group included more subjects with asthma and had a higher mean IgG4 serum level. Additional exploration according to subgroups with and without asthma found that among the patients without asthma, the SLIT group had a significantly better clinical score (P = .045). Anti-Dactylis specific IgG4 levels increased significantly in the SLIT group. SLIT with a standardized, high-dose, 3-grass pollen extract is safe and significantly improves the clinical score in patients with hay fever and without asthma during the pollen season.
    Annals of allergy, asthma & immunology: official publication of the American College of Allergy, Asthma, & Immunology 12/2007; 99(5):453-61. · 3.45 Impact Factor
  • Annales de Dermatologie et de Vénéréologie 03/2007; 134(3 Pt 1):275-6. · 0.60 Impact Factor
  • Annales De Dermatologie Et De Venereologie - ANN DERMATOL VENEREOL. 01/2007; 134(3):275-276.
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    ABSTRACT: Allergy to natural rubber latex proteins continues to be an important medical problem among health care professionals, but also in multioperated children. Clinical manifestations range from urticaria to angioedema, rhinoconjunctivitis, bronchial asthma and anaphylactic shock. The aim of this study was to investigate the efficacy and safety of a 12-month latex-specific immunotherapy in sensitized patients, most often health care workers. Twenty-three patients with latex rhinoconjunctivitis (20 of whom also had asthma) were included in this randomized, double-blind, placebo-controlled trial (11 in the active group, 12 in the placebo group). Treatment efficacy was assessed by means of symptom and medication scores. Conjunctival provocation tests and quantitative skin prick tests were also performed. The clinical index (derived by combining changes from baseline of six efficacy variables during the treatment period) did not differ significantly between treatment groups. Change from baseline of rhinitis, conjunctivitis, skin symptoms, asthma symptoms, medication score and cutaneous reactivity were not significantly different between the two groups. A nonsignificant difference in conjunctival reactivity was observed in favor of the active group (p = 0.09). Systemic reactions were much higher in the specific immunotherapy than in the placebo group. The present study failed to show a significant improvement of symptoms and medication scores, probably because of the low level of symptoms at baseline and the low maintenance dose of therapy, even if allergen-specific conjunctival reactivity decreased in the active group. Moreover, the incidence of systemic reactions was very high in the active group.
    International Archives of Allergy and Immunology 02/2006; 141(4):369-76. · 2.25 Impact Factor
  • J. Barbara, F. Leynadier
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    ABSTRACT: The best measure in preventing allergic reactions due to dust mite is avoidance, for example by isolating the elements of bedding, the major source of allergens.Objective To determine the relevance of the fabric used for the manufacturing of Immunoctem integral mattress encasings in the retention of dust mite allergens.Methods House dust was pulverized in a proof chamber and collected in a flask by aspiration. The tests were performed in absence of fabric (control series) and in the presence of fabric pieces (cotton fitted sheet or Immunoctem cover) inserted at the entrance of the aspiration circuit. Determination of total protein (Lowry modified method), Dermatophagoïdes pteronyssinus and mite allergen (ELISA methods) contents were performed in the collected dust.ResultsThe cotton fitted sheet allowed to pass 11.6% of total proteins, 15.2% of D. pteronyssinus and 12.6% of allergens, compared with the amounts obtained without any fabric. Conversely, these amounts were not detectable in the presence of the Immunoctem fabric.Conclusion The Immunoctem fabric efficiently prevented the passage of dust mite allergens. It constitutes a good tool for the application of the allergen avoidance measures such as mattress encasement, as recommended by the International Consensus.
    Revue Française d'Allergologie et d'Immunologie Clinique. 01/2006; 46(8):701-707.
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    ABSTRACT: Preventing anaphylactic reactions as a result of natural rubber latex (NRL) proteins is an important concern in anaesthesia. The clinical relevance of a bacterial/viral filter (Pall BB25) in preventing sensitization to NRL by inhalation was tested in guinea pigs. Guinea pigs (n=8-10 in each group) were exposed to aerosolized NRL-contaminated cornstarch powder or to NRL in saline for 1 h every day for 2 weeks. The experiments were repeated with a Pall BB25 filter placed over the aerosol system. Control groups were exposed to non-contaminated cornstarch or to saline alone. Three weeks after the last exposure, specific bronchial challenge was performed and thromboxane (Tx) B2 levels in bronchoalveolar lavage fluid were measured. After bronchial challenge, the animals exposed to NRL or NRL-contaminated cornstarch with the BB25 filter in place showed a level of bronchoconstriction (i.e. the variation of pulmonary insufflation pressure) not different from controls. Conversely, those exposed to NRL or NRL-contaminated cornstarch without the filter showed a higher level of bronchoconstriction (respectively, P<0.02 and P<0.001) than control. Elevated TxB2 levels were found in the lungs of the guinea pigs, which inhaled NRL or NRL-contaminated cornstarch in the absence of a filter. Animals treated with the filter showed comparable TxB2 levels with those of control. The Pall BB25 filter efficiently protected the guinea pigs from sensitization to NRL. This filter can be used as a complementary measure for avoidance of NRL contact during surgical procedures particularly if the mechanical ventilator apparatus contain NRL devices.
    BJA British Journal of Anaesthesia 09/2005; 95(3):349-54. · 4.24 Impact Factor
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    ABSTRACT: Atopic dermatitis of the head and neck (HNAD) has been recognized as a separate entity. Malassezia furfur, a lipophilic yeast, is considered to be a pathogenic allergen in this form of atopic dermatitis. The purpose of this study was to determine the level of IgE anti-M.-furfur antibodies and their relation to the severity of the disease. IgE anti-M.-furfur antibodies were assayed in 106 patients with HNAD. Controls included 25 patients with non-HNAD, 20 with nonatopic dermatitis and 16 with seborrheic dermatitis (including 4 with AIDS). There was a highly significant correlation between the level of anti-M.-furfur IgE and clinical severity. Furthermore, there was a significant but smaller correlation between total IgE and clinical severity. In patients with HNAD, total IgE was higher amongst men. IgE anti-M.-furfur antibodies are a good and specific marker for HNAD. IgE M. furfur levels are strongly correlated with the severity of the disease.
    Dermatology 02/2005; 211(2):107-13. · 2.02 Impact Factor
  • Annales De Dermatologie Et De Venereologie - ANN DERMATOL VENEREOL. 01/2005; 132:77-77.
  • Annales De Dermatologie Et De Venereologie - ANN DERMATOL VENEREOL. 01/2005; 132:77-78.
  • Annales de Dermatologie et de Vénéréologie 12/2004; 131(12):1129-1130. · 0.60 Impact Factor
  • Revue Française d Allergologie et d Immunologie Clinique 09/2004; 44(5):488-490. · 0.24 Impact Factor
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    ABSTRACT: Estimation of the allergenicity of latex gloves by measurement of total extractable protein content with the modified Lowry method is not satisfactory. Therefore, complementary methods that are accurate, sensitive, and clinically relevant are needed. The Competitive Immunoassay for Antigenic Latex Proteins (CIALP) method described in a previous study could be a reliable complementary method for estimating the allergenicity of latex gloves. Extracts from 62 powdered or powder-free gloves (16 surgical and 46 examination) were tested by the EN 455-3 modified Lowry assay, IgE-inhibition, and CIALP. The results were compared with those from 36 glove extracts reported in a previous study. Significant correlations were observed between CIALP, IgE-inhibition, and the Lowry assay for the 62 glove extracts (r between 0.79 and 0.87; p<0.001), mostly rich in proteins. After inclusion of results from the previous study, significant correlations between the three methods were again observed (r between 0.76 and 0.90; p<0.001). However, there was no correlation between CIALP or IgE-inhibition and results of the Lowry assay for gloves that had a total protein content <50 micro g/g of glove. Furthermore, 15/16 extracts with undetectable total proteins were positive in both the CIALP and IgE-inhibition methods. The modified Lowry assay alone is useful for estimating the allergenicity of latex gloves when the total protein content is >/=50 micro g/g of glove. For gloves with a total protein content <50 micro g/g of glove, complementary methods such as CIALP are necessary.
    Medical science monitor: international medical journal of experimental and clinical research 07/2004; 10(7):PI81-6. · 1.22 Impact Factor
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    ABSTRACT: Breathing is one of the most important modes of sensitization to natural rubber latex (NRL) for health-care workers, a group most at risk. Cornstarch powder (CSp) from medical powdered NRL gloves is known to be an allergen carrier, and sensitization to NRL can occur by inhaling airborne particles from such gloves. The aim of this study was to demonstrate, using an experimental model, which CSp may act as an adjuvant in NRL-induced airway hyper-responsiveness. Guinea-pigs were exposed to aerosolized NRL-contaminated CSp or to NRL in saline solution for 1 h every day for 2 weeks. The control groups were exposed either to CSp or to saline alone. An additional group of guinea-pigs was exposed to aerosolized ovalbumin (OVA) in saline. Three weeks after the last exposure, specific bronchial challenges were performed. In addition, Specific IgG and IgG1 in sera and thromboxane (Tx) B(2) levels in bronchoalveolar lavage fluid (BALF) were measured. The NRL challenge caused significant bronchospasm in the animals that had been exposed to NRL compared with those in the control groups (P<0.02). Guinea-pigs exposed to OVA also demonstrated a significant bronchospasm after OVA challenge (P<0.001). The guinea-pigs that had inhaled NRL-contaminated CSp had a significantly higher bronchoconstriction level than those that had inhaled NRL alone (P<0.02). Specific IgG and IgG1 were undetectable in sera from all groups, whereas significant amounts of TxB(2) (P<0.001) were found in the lungs of the guinea-pigs exposed to NRL or OVA. Inhaling CSp increases the airway response to NRL. The fact that specific IgG and IgG1 were not detected might be the result of an immune response limited to the airways. This finding is supported by a significant increase of TxB(2) level in the BALF of sensitized guinea-pigs.
    Clinical & Experimental Allergy 06/2004; 34(6):978-83. · 4.79 Impact Factor
  • Journal of Allergy and Clinical Immunology 03/2004; 113(2):360-1. · 12.05 Impact Factor
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    ABSTRACT: The autoimmune nature of certain forms of chronic urticaria remains debatable. Aim of the study. To find a correlation in terms of autoimmune pattern between chronic urticaria and thyroiditis using the autologous serum test and the search for anti-thyroid antibodies. Study in a single center of 59 patients having consulted for urticaria that had progressed for more than six weeks and without precise etiology. An autologous serum test was conducted and anti-thyroid autoantibodies were searched for in the serum stored after the test. Out of 59 patients, 51 had an interpretable autologous serum test and 57 underwent research for anti-thyroid antibodies. Twelve patients out 57 (21 p.cent) exhibited one or more types of positive (n=10) or borderline (n=2) anti-thyroid antibodies, and eight out of 12 (66.6 p.cent) had a known thyroid disease before the onset of urticaria. The systematic blood test permitted the discovery of 4 cases of unknown anti-thyroid antibodies. The symptoms regressed in two of these patients without any specific treatment, one patient was treated with L thyroxin for hyperthyroidism without any improvement in the symptoms and one other patient had normal thyroid function. Among these 12 patients, 11 underwent autologous serum tests, but only 3 of them exhibited clearly positive results and one was doubtful. Within the limits of this study, we found a 21 p.cent rate of patients with chronic urticaria exhibiting one or more anti-thyroid antibodies. The positivity of the autologous serum test does not appear to be related with autoimmune thyroid disorders.
    Annales de Dermatologie et de Vénéréologie 01/2004; 130(12 Pt 1):1115-8. · 0.60 Impact Factor
  • Revue Française d Allergologie et d Immunologie Clinique 01/2004; 44(1). · 0.24 Impact Factor

Publication Stats

2k Citations
439.45 Total Impact Points

Institutions

  • 2005
    • Unité Inserm U1077
      Caen, Lower Normandy, France
  • 2003
    • Assistance Publique – Hôpitaux de Paris
      Lutetia Parisorum, Île-de-France, France
  • 1999
    • Pierre and Marie Curie University - Paris 6
      Lutetia Parisorum, Île-de-France, France
  • 1996
    • University of Birmingham
      Birmingham, England, United Kingdom
  • 1988
    • Hôpital Universitaire Necker
      Lutetia Parisorum, Île-de-France, France
  • 1983
    • Centre Hospitalier Universitaire de Rennes
      • Service de chirurgie orthopédique, réparatrice et traumatologique
      Roazhon, Brittany, France