Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0042109 (urticaria)
 6,569 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Allergic drug reactions can be classified as immediate, accelerated or delayed. This classification usually correlates with the mechanism involved: immediate reactions are IgE mediated and delayed reactions are T cell dependent. We analyzed lymphocyte involvement in patients with these reactions by determining cell subpopulations, activation state and skin homing receptor expression (CLA) in blood and skin. Patients with immediate, accelerated and delayed reactions were evaluated during the acute phase and after resolution. Controls taking drugs were included. Phenotypic immunofluorescence analysis was done by flow cytometry in peripheral blood, and by immunohistochemistry in skin for delayed reactions. Forty-six patients were included, 17 with immediate reactions, 10 accelerated and 19 delayed. At the acute phase CLA was significantly increased in delayed reactions and HLA-DR in all three types of reaction. In the severest delayed reactions, Steven-Johnson/Lyell syndromes, the CD4 subsets were increased in peripheral blood and skin compared to maculopapular exanthemas and urticaria and HLA-DR when compared with urticaria. In maculopapular exanthemas CLA was significantly increased in peripheral blood and skin compared to urticaria and the severe reactions. We found that T-cells are implicated, besides delayed reactions, in immediate and accelerated reactions. In delayed reactions there is a parallelism between results found in skin and peripheral blood with a higher participation of CD4+ cells the more severe the reaction.
 ...
PMID:T cell assessment in allergic drug reactions during the acute phase according to the time of occurrence. 1656 50

The mechanisms of distant manifestation after a local allergic reaction are largely unknown. This study examined the development of cutaneous lesions in a mouse model of late allergic rhinitis (LAR). BALB/c mice were sensitized by ovalbumin (OVA) intraperitoneally two times (on days 0 and 10) and challenged by OVA intranasally on day 14. Four days after OVA challenge, nasal and cutaneous lesions including helper T (Th) responses, expression of adhesion molecules and presence of OVA and IgE were examined, and compared with unsensitized and unchallenged (control) mice. Compared with the control group, the LAR group developed LAR characterized by infiltration of lymphocytes and eosinophils, increased IgE values and increased productions of IL-4 and IL-5, but not IFN-gamma. A dominant infiltration of eosinophils and increase in mast cells, attachment of eosinophils to endothelium, intense expression of VCAM-1 on endothelium in venules and VLA-4 expression on eosinophils and mast cells were recognized in the cutaneous tissues. There were no differences in the expression of ICAM-1 on vascular endothelium and LFA-1 on infiltrated leucocytes between the two groups. CLA expression on lymphocytes was not detected, and the binding of OVA and IgE on mast cells and eosinophils was found in the cutaneous lesions in the LAR group, but not in the control group. This study suggests that acute urticaria[corrected]-like lesions in OVA-unexposed cutaneous tissues may be induced by immediate allergic reaction due to the systemic development of Th2-type response in a mouse model of LAR.
 ...
PMID:Acute urticaria[corrected]-like lesions in allergen-unexposed cutaneous tissues in a mouse model of late allergic rhinitis. 1846 71