Immediate hypersensitivity disease

Type I Reactions These reactions result from the production of IgE they are also termed immediate hypersensitivity disease. These are allergic reactions that... 

Asthma is an extremely complex condition characterized by variable and reversible airways obstmction combiaed with nonspecific bronchial hypersensitivity (1 3). The cause of asthma, which is not always readily diagnosed (4), remains unknown. Days, if not weeks, ate needed to document the spontaneous reversal of the airways obstmction ia some patients. Asthmatics experience both an immediate hypersensitivity response and a delayed late-phase reaction, each mediated by a different pathway. Chronic asthma has come to be viewed as an inflammatory disease (5). The late-phase reaction plays a key role ia iaduciag and maintaining the inflammatory state which ia turn is thought to iaduce the bronchial hyperresponsiveness (6). The airways obstmction results from both contraction of airways smooth muscle and excessive bronchial edema. Edema, a characteristic of inflammatory states, is accompanied, ia this case, by the formation of a viscous mucus which can completely block the small airways. 

Systemic anaphylaxis is the most dramatic and potentially fatal manifestation of immediate hypersensitivity, accounting for more than 500 deaths annually [ 1 ]. Despite these alarming findings, there is surprisingly limited interest and little information on how the cardiovascular system is involved in fatal and near-fatal allergic diseases. 

Schwartz LB, Austen KF. The mast cell and mediators of immediate hypersensitivity. In Samter M, Talmage DW, Frank MM, et al, eds. Immunologic Diseases, 5th ed. Boston, Little, Brown, 1995. 

E. Abnormal Immune Responses Abnormal immune responses include hypersensitivity, autoimmunity, and inununodeficiency states. Immediate hypersensitivity is usually antibody-mediated and includes anaphylaxis and hemolytic disease of the newborn delayed hyptersensitiv-ity, associated with extensive tissue damage, is cell-mediated. Autoinununity arises from self-reactive lymphocytes that react to one s own molecules, or self-antigens. Examples of autoimmune diseases that are amenable to dmg treatment include rheumatoid arthritis and systemic lupus erythematosus. Immunodeficiency states may be genetically acquired (eg, Di George s syndrome) or result from extrinsic factors (eg, AIDS). 

Other foods have been known to be linked to delayed hypersensitivities. Symptoms associated with delayed hypersensitivity reactions may not begin to appear until 24 h after ingestion of the offending food. The symptoms of delayed hypersensitivity reactions do not reach the severity involved in immediate hypersensitivity. However, thresholds triggering reactions, or the level of tolerance for the offending food, is equally low for delayed as well as immediate hypersensitivities. Mechanisms involved in delayed hypersensitivities remain poorly defined, except perhaps for celiac disease (Taylor, 2000 Kagnoff, 2007 Braini et al., 2008). 

Lutsky II, Neuman I (1975) Laboratory dander allergy. I An occupational disease. Ann Allergy 35 201-205 Thomsen RJ, Honsinger RW (1987) Immediate hypersensitivity reaction to amphibian serum manifesting as eczema. Arch Dermatol 123 1436-1437... 

This chapter will review our current knowledge about the pathogenesis of allergic skin disorders, in particular atopic dermatitis (AD) and urticaria. Anti-lgE therapy has not been systematically studied in these skin diseases. Therefore we will discuss the role of IgE in their pathogenesis and provide a scientific rationale for use of anti-IgE treatment in these diseases. Recent studies indicate that the IgE molecule has a multifunctional role in these diseases, acting as both a target and a key player in the elicitation of allergen-induced immediate hypersensitivity reactions and cell-mediated responses. 

The balance of evidence indicates that parasite-specific IgE may contribute to immediate hypersensitivity phenomena and parasite-directed inflammatory reactions (ADCC) in human helminth infections. IgE-induced mast cell degranulation may play a significant role in the allergic phenomena associated with early or acute infections in recruitment of effector cells to the tissue sites of helminth parasites, although the effectiveness of these mechanisms in parasite killing is not clear. The intense inflammation that results is the principal cause of the tissue pathology and clinical disease associated with these infections. In the absence of IgE, it is probable that other immunoglobulin isotypes can participate in ADCC reactions with similar efficiencies. Observations from primary infections with helminths in humans indicate that IgE is unlikely to have a critical role in host... 

Radiocontrast media (RCM) are highly concentrated solutions of triiodinated benzene derivatives used for performing diagnosis and treatment of vascular disease and enhancement of radiographic contrast [1,2]. However, adverse reactions after RCM administration are common [3]. The frequency and mechanisms of hypersensitivity reactions differ between monomeric and dimeric as well as between ionic and non-ionic types of RCM. Mild immediate reactions have been reported to occur in 3.8-12.7% of patients receiving ionic monomeric RCM and in 0.7-3.1% of patients receiving non-ionic RCM [4-6]. Severe immediate adverse reactions to ionic RCM have been reported in 0.1-0.4% of intravenous procedures, while reactions to nonionic iodinated RCM are less frequent (0.02-0.04%) [4-7]. Fatal hypersensitivity... 

Hypersensitivity reactions Stop all drugs and evaluate at the first sign of a hypersensitivity reaction. If isoniazid must be reinstituted, give only after symptoms have cleared. Restart the drug in very small and gradually increasing doses and withdraw immediately if there is any indication of recurrent hypersensitivity reaction. Renai/Hepatic function impairmentMon ior patients with active chronic liver disease or severe renal dysfunction. 

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