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F Leynadier

Publications and source records attributed to F Leynadier.

At least 37 records · Page 2Linked to original sources
PubMed1996

[What is allergy?].

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False Positive Reactions↗
PubMed1996

Chronic generalized eczema caused by multiple dye sensitization.

Textile dye sensitization is rare; its low incidence (1.4% to 5.8%) is most likely because dye contact allergy is not suspected and therefore not tested. The greatest number of positive test results are obtained for disperse dyes. We report an uncommon observation of severe and chronic textile dye dermatitis with positive patch test results to Disperse Blue 106, Disperse Blue 124, Disperse Brown 1, Disperse Yellow 3, and p-aminophenol.p-aminophenol, Disperse Blue 124, and Disperse Blue 106 are derived from p-phenylenediamine, but this allergen seems to be unreliable as a detector of textile dye allergy. The admittedly allergic capacity of disperse dyes and the increasing fabrication of synthetic fibers (acrylics and polyesters) usually colored with this group of dyes could induce more frequent textile sensitization.

Adult↗
PubMed1996

[Toxicoderma caused by prednisone and prednisolone. Value of skin tests in the screening of cross sensitivity].

INTRODUCTION: Allergic reactions to general corticosteroid therapy are uncommon. CASE REPORT: We report a patient with systemic lupus erythematousus who developed skin rash after initiation of prednisone then prednisolone therapy. Histology evidence suggested leukocytoclastic vasculitis. The skin tests (prick tests, intradermoreactions and patch-tests) using a battery of injectable corticosteroids showed a highly positive reaction to prednisolone, methylprednisolone and dexamethasone on the intradermo-reactions 24 hours later. Histology examination of a positive-response showed leukocytoclastic vasculitis associated with eczematiform alterations of the epidermis compatible with a drug reaction. The skin tests however were negative for betamethasone, triamcinolone, paramethasone and hydrocorticose. The patient was treated with betamethasone and no skin reaction was observed. DISCUSSION: Skin tests, particularly intradermo-reactions read 24 hours later would appear to be useful in identifying possible cross-sensitivity.

Aged↗
PubMed1995

Flow cytometric monitoring of allergen induced basophil activation.

Human basophils express many clustered differentiation antigens (CD), including CD45; however, none are specific for these cells. In a previous study, we described a two-color immunofluorescence procedure, employing antibodies to CD45 and IgE for the cytometric evaluation of basophils. In the present work, we show that when sensitized basophils are stimulated by allergenic preparations, they demonstrate an upregulation of CD45 as well as a decrease in anti-IgE binding. Since CD45 antigen modulation was observed with all aeroallergens tested and the decrease in IgE expression varied with allergenic preparations, the measurement of CD45 upregulation was used to evaluate basophil activation. Using this approach, reproducible results were observed when atopic patients were tested at different time intervals. In addition, we show that the upregulation of CD45 on allergen stimulated basophils is a very rapid phenomenon that is observed after a few minutes and that this rapid flow cytometric method can also be used for investigations on nonallergenic mediators of basophil stimulation such as calcium ionophores.

Adult↗
PubMed1995

[Cutaneous reactions to heparin: immunological and clinical aspects].

Skin reactions to heparin are rare, the most frequent manifestation being skin necrosis. Reactions occur either as an isolated manifestation or within a context of heparin-induced thrombopenia. Urticarious and eczematous reaction, either localized at injection sites or with a general distribution, have been recently reported. In all cases, it is mandatory to withdraw heparin therapy. Such accidents can be observed with all types of heparin (standard heparin and low-molecular weight heparin). Cross-reactions between two types of heparin are frequent. Skin tests can be used to guide heparintherapy.

Drug Eruptions↗
PubMed1995

Systemic reactions to the Samsum ant: an IgE-mediated hypersensitivity.

BACKGROUND: In the United Arab Emirates the sting of the Pachycondyla sennaarensis ant (PSA) causes allergic reactions in certain persons. It is a common problem and is becoming a public health hazard. Up to now the diagnosis has been based only on the history, because the mechanism of the reaction was not yet established. OBJECTIVE: The aim of our study was to prepare an allergenic extract that would be used for skin tests and to prepare a reagent for specific IgE titration. Results of both skin tests and specific IgE were to be compared with the clinical history. METHODS: We studied 31 patients with anaphylactic reactions and performed clinical examinations, skin tests, and specific IgE antibody titrations. A control group of 22 subjects were also studied. RESULTS: In 30 of 31 patients (97%) findings of PSA skin tests and/or specific IgE were positive. In the control groups PSA skin test results were negative in 86% and negative for specific IgE in 68%. CONCLUSION: The study shows that the mechanism of the reaction to the sting of the PSA is a type I IgE-mediated hypersensitivity and that the diagnosis can now be confirmed by skin tests and specific IgE determination.

Adolescent↗
PubMed1995

Hypersensitivity to azathioprine mimicking gastroenteritis. Absence of recurrence with 6-mercaptopurine.

Hypersensitivity mimicking gastroenteritis is a rare complication of azathioprine therapy for which the mechanism is unknown. We report a case of devastating diarrhoea and vomiting due to azathioprine treatment in which hypersensitivity to the imidazole moiety of azathioprine was demonstrated. This has important therapeutic implications: in this situation, 6-mercaptopurine, which is the portion of azathioprine responsible for the cytotoxic therapeutic effect, can be administered without recurrence of side-effects.

Adult↗
PubMed1995

[Practical aspects of leukotriene E4 determination in urine].

Leukotrienes constitute a class of potent biological mediators of inflammation and anaphylaxis. However, their routine assay in various biological fluids is restricted by the complexity of the methodology. Previously this could only be performed by research laboratories with high pressure liquid chromatography and radioimmunological capabilities. The recent availability of kits for immunoenzymatic assay of leukotrienes offers a new tool for clinical laboratories provided the limitations of the method are understood. We suggest a simplified methodology for direct urinary LTE4 detection and outline a number of areas of concern encountered with this method.

Adult↗
PubMed1994

[Cold urticaria].

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Cold Temperature↗
PubMed1994

[Why are some allergens enzymes?].

In the last ten years, progress in the field of allergy research has led to the purification of some of the major allergens and to a better knowledge of their physico-chemical properties. A number of studies have shown that some allergens have enzymatic activities. Molecular biology has provided the means to clone and sequence genes encoding these allergens and to produce recombinant allergens in yeast and bacteria. Epitope mapping of natural and synthetic allergens, using polyclonal or monoclonal antibodies and cell-stimulation tests, has also contributed greatly to the understanding of their immunogenicity and allergenicity. Analysis of these new data allow us to explain why some allergens are enzymes.

Acari↗