Delayed allergic reactions

Immediate hypersensitivity reactions to paramethasone acetate, causing widespread eruptions, have been described in at least four cases. Delayed allergic reactions are less common. 

Hearing disturbances attributable to contrast agents are extremely rare. The hearing loss in this patient developed more than 1 hour after the injection of iohexol, without any evidence of other causes. The authors suggested that the hearing disturbance might have been attributable to cochlear impairment caused by a delayed allergic reaction or chemical toxicity of the contrast medium. 

Vega JM, Blanca M, Carmona MJ, Garcia J, Claros A, Juarez C, Moya MC. Delayed allergic reactions to beta-lactams. Four cases with intolerance to amoxicillin or ampicillin and good tolerance to penicillin G and V. Allergy 1991 46(2) 154-7. 

Polyethylene glycols administered topically may cause stinging, especially when applied to mucous membranes. Hypersensitivity reactions to polyethylene glycols applied topically have also been reported, including urticaria and delayed allergic reactions. 

It is important to recognize that delayed chemical allergy can occur even some time afto" the chemical has been removed. Contact with poison ivy is a familiar example of an exposure that causes a delayed allergic reaction. Also, just as people vary widely in their susceptibility to sensitization by environmental allergens such as dust and poUen, individuals may also exhibit wide differences in their sensitivity to laboratory chemicals. Examples of substances that may cause allergic reactions in some individuals include diazomethane, dicyclohexylcarbodiimide, formaldehyde, various isocyanates, benzyUc and aUyUc halides, and certain phenol derivatives. 

Immunologic Povidone-iodine has been associated with a wide range of allergic reactions from minutes to hours after exposure. However delayed allergic reactions can also occur [27 ]. 

These substances in powder form were responsible for both immediate and delayed allergic reactions in four pharmaceutical industry workers. Two of them gave positive reactions on patch testing, while the other two presented an immediate reaction to a scratch test (Moller and Kromann 1989). 

A Canadian study found the overall prevalence of allergic reactions to alcoholic beverages to be 0.46% (Israel et al. 1992). Hypersensitivity to wines has been attributed to histamine and other amines as well as sulfites (Dahl et al. 1986), but the alcohol itself may also be responsible. An extensive review of the subject (Ophaswongse and Maibach 1994) concluded that alcohol can be an allergen and cause both contact urticaria and irritant and allergic contact dermatitis. They documented 15 reports of either immediate or delayed allergic reactions after... 

In the course of immediate or delayed allergic reactions the amount of histamine shown to be present does not correspond with the disturbance in the vascular permeability. 

Immunologic Acute and delayed allergic reactions after the intravenous administration of iodinated low-osmolar contrast media are well documented but rare. They range in intensity from mild, involving urticaria, rash, and pruritus, to severe, including cardiopulmonary arrest and death. 

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