1,721,012 research outputs found
Cosmetic Facial Peel-Induced Contact Anaphylaxis: Chestnut Allergy Without Latex-Fruit Syndrome
Cosmetic Facial Peel-Induced Contact Anaphylaxis: Chestnut Allergy Without Latex-Fruit Syndrome
Heparin Allergy: Delayed-Type Non–IgE-Mediated Allergic Hypersensitivity to Subcutaneous Heparin Injection
Itching erythematous or eczematous plaques around injection sites are quite frequent side effects of heparin treatment and clinical symptoms of delayed-type non-IgE-mediated allergic hypersensitivity (DTH) to heparin. For diagnosis, intradermal, patch, and subcutaneous challenge tests with heparins are suitable. In most cases, changing the subcutaneous therapy from unfractionated to low molecular weight heparin or treatment with heparinoids does not provide improvement because of extensive cross-reactivity. Hirudin polypeptides, which exhibit a different chemical structure, are a safe therapeutic alternative for subcutaneous application, however. Importantly, despite DTH to subcutaneously injected heparins, most patients tolerate heparin intravenously. Moreover, in case of therapeutic necessity and DTH to heparins, the simple shift from subcutaneous to intravenous heparin administration without prior testing may be justified
The Complex Clinical Picture of Side Effects to Anticoagulation
Inflammatory plaques at injection sites are frequent side effects of heparin treatment and a clinical symptom of delayed-type hypersensitivity (DTH) to heparin. In most cases, changing the subcutaneous therapy from unfractionated to low-molecular-weight heparin or treatment with heparinoids does not provide improvement because of extensive cross-reactivity. Because of their completely different chemical structure, hirudins are a safe alternative for anticoagulation. Despite DTH to subcutaneously injected heparins, patients tolerate heparin intravenously. Therefore, in case of therapeutic necessity and DTH to heparins, the simple shift from subcutaneous to intravenous heparin administration is justified. Skin necrosis is a rare complication of anticoagulation. Heparin-induced skin necrosis is 1 of the symptoms of immune-mediated heparin-induced thrombocytopenia and should result in the immediate cessation of heparin therapy to prevent potentially fatal thrombotic events. This is in contrast to coumarin-induced skin necrosis, where therapy may be continued or restarted at a lower dose
Diagnostic testing in suspected fluoroquinolone hypersensitivity
P>Background Because of their broad antibacterial activity in the gram-negative and gram-positive spectrum, high oral bioavailability, and good tissue penetration, fluoroquinolone antibiotics are widely used. Besides direct drug-related side-effects, fluoroquinolones may cause hypersensitivity reactions. Objective The aim of this retrospective analysis was to present the results of diagnostic testing in cases of clinically suspected fluoroquinolone-induced immediate or delayed hypersensitivity. Methods We studied 101 patients with a history of immediate or delayed hypersensitivity symptoms in temporal relation to treatment with a fluoroquinolone antibiotic using standardized skin testing, followed by oral challenges. Patients with anaphylaxis symptoms were further evaluated with in vitro tests. Results Fluoroquinolone hypersensitivity was excluded in 71 patients by tolerated oral challenge tests. During positive challenge tests, six patients (three out of these had positive and three had negative skin prick tests) developed anaphylaxis symptoms but the presumed IgE-mediated mechanism could not be confirmed by in vitro tests. Patch testing was constantly negative; however, in two patients a rash was induced by the challenge tests. Conclusion History alone leads clearly to a considerable over-estimation of fluoroquinolone hypersensitivity. Moreover, skin or in vitro tests do not seem to be very useful in identifying hypersensitive patients. Challenge tests appear to be necessary for definitely confirming or ruling out fluoroquinolone hypersensitivity. Cite this as: C. S. Seitz, E. B. Brocker and A. Trautmann, Clinical & Experimental Allergy, 2009 (39) 1738-1745
Drug-induced exanthems: Correlation of allergy testing with histologic diagnosis
Background: Skin biopsies are commonly performed to confirm drug-induced exanthem (DIE). However, the relevance of histologic examination in discriminating between DIE and non-DIE (NDIE) is controversial. Objective: A retrospective analysis was performed to evaluate the reliability of histologic diagnosis of DIE. Methods: In all, 91 patients with a skin biopsy specimen of an acute exanthem temporally related to a single identifiable drug underwent complete allergy testing. Their biopsy specimens were retrospectively re-evaluated by 2 dermatopathologists blinded to the original reports to test for discrimination between DIE versus NDIE. Results: In 35 patients, non-IgE-mediated drug allergy was confirmed by allergy testing, whereas in 56 patients drug hypersensitivity could be excluded. Sensitivity of pathology reports for diagnosis of DIE reached 62.9% with a positive predictive value of 40.7%. Specificity was 41.1% with a negative predictive value of 69.7%. No significant difference in tissue eosinophilia was detected between DIE and NDIE. Limitations: This was a retrospective study. Conclusions: Dermatopathologic evaluation of skin biopsy specimens is of limited use in differentiating between DIE and NDIE. All efforts should be made to subject these patients to thorough allergy testing for definitely confirming or ruling out drug hypersensitivity
Aminopenicillin-associated exanthem: lymphocyte transformation testing revisited
BackgroundThe lymphocyte transformation test (LTT) has been promoted as in-vitro test for diagnosis of drug hypersensitivity. For determination of statistical LTT sensitivity, series of patients with clinically uniform reactions followed by complete drug hypersensitivity work-up are mandatory. Assessment of LTT specificity requires control patients who tolerated exposure to the drug studied. ObjectiveTo prospectively determine the diagnostic value of the LTT in a clinically and diagnostically well-defined series of patients. MethodsPatients with exanthematous skin eruptions after ampicillin (AMP) intake were included in this study. After exclusion or confirmation of delayed-onset allergic AMP hypersensitivity by skin and provocation testing, two independent LTTs were performed: one standard LTT and a modified LTT with additional anti-CD3/anti-CD28 monoclonal antibody stimulation. ResultsBy testing, delayed-onset allergic AMP hypersensitivity was diagnosed in 11 patients and definitely ruled out in 26. The standard LTT reached a diagnostic sensitivity of 54.5% while the modified LTT yielded 72.7%. However, the methodical test modification resulted in a decline of specificity from 92.3% (standard LTT) to 76.9%. Conclusions and Clinical RelevanceIn cases of AMP-associated exanthems, the diagnostic value of the LTT compared with routine allergy testing is limited. When evaluating such exanthems, provocation testing remains the gold standard. Delayed reading of intradermal skin tests remains most useful to avoid positive provocation reactions
Leg Ulceration in Rheumatoid Arthritis - An Underreported Multicausal Complication with Considerable Morbidity: Analysis of Thirty-Six Patients and Review of the Literature
Background: Rheumatoid arthritis (RA) is a systemic inflammatory disease which may present with extra-articular symptoms, including cutaneous manifestations. Ulcerated rheumatoid nodules, necrotic vasculitic lesions and pyoderma gangrenosum are fairly characteristic and well-recognized causes of skin ulcers in RA. However, most RA patients develop leg ulcers due to other pathophysiological factors posing a diagnostic and therapeutic challenge and leading to considerable morbidity. Methods: A retrospective chart analysis of all patients with RA and leg ulcers hospitalized at our Dermatology Department between January 1998 and March 2008 was performed to evaluate risk factors and identify underlying conditions that predispose RA patients to the development of leg ulcers. Results: A total of 36 patients with RA and leg ulcers were identified. Three patients presented with necrotizing vasculitis and 2 with pyoderma gangrenosum. Chronic venous insufficiency was diagnosed as the underlying cause of leg ulcers in 8 patients, peripheral arterial disease in 4 patients, and combined arterial and venous malfunction in 3 patients. Five patients suffered from pressure ulcers. Interestingly, in 11 patients (31%) other underlying causes besides constricted mobility followed by secondary lymphedema could not be identified, and these ulcers were classified as 'inactivity leg ulcers'. Conclusions: The majority of leg ulcers in patients with RA are due to underlying venous/arterial malfunction while vasculitic or traumatic ulcers are less common. Additionally, we identified a relevant subgroup of patients with 'inactivity ulcers' due to impaired mobility and consecutive lymphedema. Morphology and localization of ulcerations as well as duplex sonography provide the most important clues for accurate diagnosis, ensuring adequate treatment. Copyright (C) 2010 S. Karger AG, Base
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