Cross-allergy

Some types of allergic reaction, for example immediate or delayed-type skin allergies, serum-sickness-like reactions and anaphylactic reactions, may occur in a proportion of patients given penicillin treatment. There is some, but not complete, cross-allergy with cephalosporins. 

Allergy to steroids of any type is unusual, but it has been reported with both corticosteroids and sex hormones, and cross-allergy can occur. 

Because penicillins and cephalosporins have a common chemical structure, cross-allergies occur with these drugs. Thus before initiating therapy with a penicillin. 

The cephalosporins are contraindicated in patients with known allergies or intolerances to any of the cephalosporins. Because the penicillins and cephalosporins have a common chemical structure, cross-allergies occur with these drugs. Thus before initiating therapy with a cephalosporin, careful inquiry should be made concerning previous hypersensitivity reactions to the other drugs. Because a secondary vitamin K deficiency can develop with cephalosporin use, the cephalosporins are contraindicated in patients with hemophilia. Cefaclor is also contraindicated in any patient with previous drug-related joint and skin reactions. 

There is cross-allergy between all the various forms of penicillin, probably due in part to their common structure, and in part to the degradation products common to them all. Partial cross-allergy exists between penicillins and cephalosporins (a maximum of 10%) which is of particular concern when the reaction to either group of antimicrobials has been angioedema or anaphylactic shock. Carba-penems (meropenem and imipenem-cilastatin) and the monobactam aztreonam apparently have a much lower risk of cross-reactivity. 

Life-threatening anaphylactic reactions that rarely occur during general anesthesia are mostly due to neuromuscular blockers. They may be due to cross-allergy mediated by drug-specific IgE antibodies to the quaternary ammonium moiety of the neuromuscular blocker molecule, perhaps with a contribution from IgE-independent mechanisms. Quaternary ammonium compounds, such as benzalkonium, in cosmetics and toiletries may play a role in sensitization (7). 

Sensitization (rash, drug fever) after parenteral administration of kanamycin is less frequent than with streptomycin. Anaphylaxis has only rarely been described. Cross-allergy with the other aminoglycosides is frequent (4). 

Hypersensitivity reactions are frequent early in a course of penicillamine, with urticarial or maculopapular rashes, fever, and lymphadenopathy. Cross-allergy to penicillin can occur. In addition, the use of penicillamine can be complicated by a unique variety of often serious autoimmune reactions, involving the skin, kidneys, liver, lungs, muscles, or other organs. Proteinuria is found in more than 10% of patients and sometimes develops into the nephrotic syndrome. Pemphigus, myasthenia gravis, polymyositis, or a lupus-like syndrome occur in smaller percentages. 

Hypersensitivity (possible cross-allergy with sulfonamides)... 

Freste CK, Lpvik M, Wiker HG, Egaas E (2004). A case of peanut cross-allergy to lupine flour in a hot dog bread. Int. Arch. Allergy Immunol., 135 36-39. 

Eriksen K (1978) Cross allergy between paranitro compounds with special reference to DNCB and chloramphenicol. Contact Dermatitis 4 29-32 Fanta D, Mischer P (1976) Contact dermatitis from tromantadine hydrochloride. Contact Dermatitis 2 282-284... 

Cross-allergies to different sulfonamides can appear, but this is not the rule. The frequency of the sensitization by another sulfonamide is about 20%. 

On patch testing, cross allergy has been found between compounds that are chemically closely related, especially between reactive diluents. Reactive diluents do not produce cross allergy with DGEBA epoxy resins, and contact allergy to reactive diluents is not revealed by testing with the standard epoxy resin. Patients who are allergic to cycloaliphatic epoxy resins often react to reactive diluents, and vice versa (Jolanki... 

A structural similarity or cross allergy between MDI and MDA has been considered as an explanation for simultaneous reactions to MDI and MDA (Fregert 1967 Rothe 1976). MDA may also have formed as a result of hydrolysis of MDI (Buist and Gudgeon 1970). The positive TDI reactions in patients exposed to MDI can be explained by cross reactions between MDI and TDI, which has been confirmed by mouse-ear-swelling tests (Tanaka et al. 1987), although the reactions may also be due to concomitant sensitization to the chemicals. Commercial MDI and PAPI may contain as much as 21% TDI (Lubach 1978). 

Allergic contact dermatitis caused by n-octyl-iso-thiazolinone has been reported in paint-factory workers who had been exposed to the chemical as dye mixers (Thormann 1982 Mathias et al. 1983). It is chemically related to i,2-benzisothiazolin-3-one. One of the seven Swedish construction painters who were patch-test positive to i,2-benzisothiazolin-3-one also reacted to n-octyl-isothiazolinone (Fischer et al. 1995). Cross-allergy between n-octyl-isothiazolinone and chloromethyl-isothiazolinone has not been demonstrated (Emmett et al. 1989). 

Chemical similarities can quite easily explain the observation of cross-allergies. Small conformational differences are enough indeed to create common epitopes (etymologically, superficial place ). An epitope is a part of molecule with a specific three-dimensional structure. One more time, we can see the importance of molecular structures in biology. Epitope is also called antigenic determinant. It can be incorporated in a macromolecular antigen by a group of specific amino acids, often exposed on the surface of the molecule (Fig. 3.27). ... 

Immune cross-reactivity of benzylpenicillin and ceph-alothin was reported.23 cross-allergenicity to penicillins and cephalorsporins was noted.23 in contrast, in a study on the allergenicity and toxicity of cephaloridlne and ceph-alothin, no cross-allergy with the penicillins was observed.27 An orally effective cephalosporin, e.. cephalexin, as well as oral penicillins, would appear to have greatly less sensitizing potential than those given by injection. 

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