Type IV Allergic Reaction

Delayed type hypersensitivty (DTH) reactions (synonym type IV allergic reactions) are exaggerated, T-lymphocyte mediated, cellular immune reactions to foreign substances, which require one to two days to manifest clinical symptoms. 

Type IV allergic reactions are cell-mediated hypersensitivity reactions which are characterized by the expansion of T lymphocytes specific for foreign substances exposed on cell surfaces. In type FVa allergic reactions, this results in the cell-mediated destruction of the cells, whereas in type FVb allergic reactions an... 

A variety of agents, including antibiotic penicillin, beryllium, mercaptobenzothiazole, phthalic anhydride, and dichromate salts, cause type IV allergic reactions, one common symptom of which is contact dermatitis. 

A 72-year-old man developed a generalized maculo-papular rash 12 hours after taking co-codamol (codeine 10 mg plus paracetamol 500 mg) (8). The lesions persisted for 7 days, became scaly, and disappeared. He later reported a similar skin condition after having taken a combination of acetylsalicylic acid, codeine, and caffeine. Patch tests gave a positive result for codeine, suggesting a type IV allergic reaction. 

Sulphonamides are usually the cause of type III or type IV allergic reactions, such as serum-sickness syndrome, or probably, the majority of maculopapular rashes. 

Despite their anti-inflammatory and immunosuppressive properties, CSs can provoke both immunological and inflammatory responses, occasionally inducing immediate type 1 and delayed type IV allergic reactions. Type 11 cytotoxic and type III immune complex reactions do not appear to have been reported. 

Immunologic Type IV allergic reactions to lidocaine are rare. However, cross-reactivity to the amide local anesthetics has been described [74" ]. 

Type II, III, and IV allergic reactions are variants of physiologic defense mechanisms only relevant in special situations, which follow a common pathologic pattern. In general, treatment of these forms require antiinflammatory ( inflammation) or immunosuppressive strategies ( immunosuppression). Therefore, only therapy of Type I reactions will be described here. 

Allergic eye disease may result from a type I or type IV hypersensitivity reaction. Typically, on initial exposure to the allergen, there are no clinical manifestations. In contrast, clinical manifestations occur in sensitized individuals or... 

Three cases of allergic dermatitis have been described after intravesical mitomycin (23). A type IV hypersensitivity reaction was demonstrated on patch-testing. Six cases of purpuric allergic drug eruption from intravesicular mitomycin have been reported (24). 

IV reactions as clinical correlates. Nevertheless, the penicillin RAST offers a reliable and safe way to explore at least type I allergic reactions. An extension of that procedure to other drugs commonly responsible for allergic reactions is therefore highly desirable. 

For these reasons, lymphocyte transformation and leukocyte migration inhibition tests have been widely used to investigate type IV allergic drug reactions. 

The range and diversity of adverse effects provoked by contrast media remain poorly understood and hence difficult to categorize. For the allergist and clinical immunologist used to thinking of immediate reactions as type I allergic responses mediated by IgE antibodies and delayed reactions as type IV hypersensitivity reactions mediated by antigen-specific effector T cells, adverse reactions to contrast media, divided... 

N-DEX Eree is free from the accelerators common in other disposable nitrile gloves, which have been linked to workplace conditions like Type IV dermatitis. It s free from natural rabber latex and Type I allergic reactions linked to latex proteins. The high-visibility green glove is ideal for jobs where increased visibility and color-coded operations are critical. Available in a smooth finish or with new textured... 

Currently allergic reactions are classified into four types on the basis of different reaction patterns. Whereas types I—III are dependent on antibodies, the type IV reaction is mediated by cellular immune reactions. 

Allergic reactions (especially those of type IV) can lead to disorders which resemble autoimmune or chronic inflammatory diseases. If an immediate elimination of the antigen is not feasible, immunosuppressive drugs can represent a reasonable addendum. 

Toxicology. NRL causes allergic skin reactions of type I (immediate-type) and type IV [delayed-type hypersensitivity (DTH)]. 

Amelioration of allergic reactions to Blood or plasma, anaphylaxis as an adjunct to epinephrine and other standard measures after the acute symptoms have been controlled, other uncomplicated allergic conditions of the immediate type when oral therapy is impossible or contraindicated IM. IV, SC 5-20 mg/day in 2 divided doses. Maximum 40... 

Most anaphylactoid reactions are due to a direct or chemical release of histamine, and other mediators, from mast cells and basophils. Immune-mediated hypersensitivity reactions have been classified as types I-IV. Type I, involving IgE or IgG antibodies, is the main mechanism involved in most anaphylactic or immediate hypersensitivity reactions to anaesthetic drugs. Type II, also known as antibody-dependent hypersensitivity or cytotoxic reactions are, for example, responsible for ABO-incompatible blood transfusion reactions. Type III, immune complex reactions, include classic serum sickness. Type IV, cellular responses mediated by sensitised lymphocytes, may account for as much as 80% of allergic reactions to local anaesthetic. 

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