Cephalosporins allergy anaphylaxis

An accurate molecular definition of cephalosporin allergy is not currently available. Relevant determinants of cephalosporin-induced anaphylaxis may not reside in the bicyclic core, but rather in the side chain (164,165). 

Neither in vitro tests nor skin tests reliably predict cephalosporin allergy (166). The true frequency of allergic reactions in penicillin-allergic patients exposed to cephalosporins has been estimated to be 1 or 2% (167). Nevertheless, when there is a history of penicillin anaphylaxis or other severe IgE-mediated reactions, it is wise to avoid cephalosporins. 

Verify the patient s allergy history and the type of reaction experienced. Attempt to discern between true allergy and adverse event. (3-Lactam-allergic patients may receive clindamycin, vancomycin, or other antimicrobials. Crossreactivity between penicillin allergy and cephalosporins is low but cephalosporins should be avoided in patients with a history of anaphylaxis to penicillins. 

Because of cross-reactions between cephalosporins and penicillins, caution should be used when prescribing cephalosporins to patients with penicillin allergy. If a patient had anaphylaxis, angioedema, or urticaria fol-... 

Cephalosporins are sensitizing and may elicit a variety of hypersensitivity reactions that are identical to those of penicillins, including anaphylaxis, fever, skin rashes, nephritis, granulocytopenia, and hemolytic anemia. However, the chemical nucleus of cephalosporins is sufficiently different from that of penicillins so that some individuals with a history of penicillin allergy may tolerate cephalosporins. The frequency of cross-allergenicity between the two groups of drugs is uncertain but is probably around 5-10%. However, patients with a history of anaphylaxis to penicillins should not receive cephalosporins. 

Cross-reactivity between pencillins and cephalosporins ranges from 5% to 10%. Even though some patients with a history of penicillin allergy may tolerate cephalosporins, patients with a history of anaphylaxis to penicillin should not receive cephalosporins. 

Allergy Cephalosporins cause a range of allergic reactions from skin rashes to anaphylactic shock. These reactions occur less frequently with cephalosporins than with penicillins. Complete cross-hypersensitivity between different cephalosporins should be assumed. Cross-reactivity between penicillins and cephalosporins is incomplete (5-10%), so penicillin-allergic patients are sometimes treated successfully with a cephalosporin. However, patients with a history of anaphylaxis to penicillins should not be treated with a cephalosporin. 

From Harle DG, Baldo BA. Drugs as allergens An immunoassay for detecting IgE antibodies to cephalosporins . Int Arch Allergy Appl Immunol. 1990 92 439. Reprinted with permission from S. Kaiger AG, Basel IgE in serum from patient with anaphylaxis to cephalothin... 

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