β-lactam allergy
From IDWiki
Cross-Reactivity
- Cross-reactivity between penicillins and cephalosporins is mediated by homology of the R1 side chains, referring to the C6 side chain in penicillins or the C7 side chain in cephalosporins
- Cross-reactivity within cephalosporins is mediated both by homology of the R1 side chains and also R2 side chains, referring to the C3 side chain
Antibiotic | R1 | R2 | ||||||||
---|---|---|---|---|---|---|---|---|---|---|
G1 | G2 | G3 | G1 | G2 | G3 | G4 | G5 | G6 | G7 | |
Penicillins | ||||||||||
Penicillin | X | |||||||||
Ampicillin | X | |||||||||
Amoxicillin | X | |||||||||
First-Generation Cephalosporins | ||||||||||
Cefazolin | ||||||||||
Cephalexin | X | X | ||||||||
Cefadroxil | X | X | ||||||||
Cephalothin | X | X | ||||||||
Second-Generation Cephalosporins | ||||||||||
Cefotetan | X | |||||||||
Cefoxitin | X | X | ||||||||
Cefuroxime | X | |||||||||
Cefaclor | X | |||||||||
Third-Generation Cephalosporins | ||||||||||
Cefotaxime | X | X | ||||||||
Ceftriaxone | X | |||||||||
Ceftazidime | X | |||||||||
Cefixime | X | |||||||||
Cefdinir | ||||||||||
Fourth-Generation Cephalosporins and Higher | ||||||||||
Cefipime | X | |||||||||
Ceftaroline |
R1 Side Chains (C6 and C7)
- Group 1: penicillin, cephalothin, cefoxitin; similar to ticarcillin
- Group 2: amoxicillin, ampicillin, cefaclor, cephalexin, cefadroxil; similar to penicillin piperacillin
- Group 3: cefipime, cefotaxime, ceftriaxone; similar to ceftazidime and aztreonam
- Ceftazidime and aztreonam; similar to group 3
R2 Side Chains (C3)
- Group 1: cefadroxil, cephalexin
- Group 2: cefotetan
- Group 3: cefotaxime, cephalothin
- Group 4
- Group 5: cefuroxime, cefoxitin
- Group 6: cefixime
- Group 7: ceftazidime
Hypersensitivity Reactions
- Type I (IgE-mediated)
- Anaphylaxis
- Itchy rash
- Penicillins should be avoided
- Type II (IgG-mediated)
- Non-itchy rash
- Rash will improve if treatment continues, no need to avoid penicillins
- Type IV (cell-mediated)
- Toxic epidermal necrolysis
- Stevens-Johnson syndrome
- Penicillins should be avoided
Further Reading
- Zagursky RJ and Pichichero ME. Cross-reactivity in β-Lactam Allergy. J Allergy Clin Immunol Pract. 2018;6(1):72-81.e1. doi: 10.1016/j.jaip.2017.08.027
References
- ^ Brittany Kula, Gordana Djordjevic, Joan L. Robinson. A Systematic Review: Can One Prescribe Carbapenems to Patients With IgE-Mediated Allergy to Penicillins or Cephalosporins?. Clinical Infectious Diseases. 2014;59(8):1113-1122. doi:10.1093/cid/ciu587.
- ^ Anna R. Wolfson, Emily M. Huebner, Kimberly G. Blumenthal. Acute care beta-lactam allergy pathways: approaches and outcomes. Annals of Allergy, Asthma & Immunology. 2019;123(1):16-34. doi:10.1016/j.anai.2019.04.009.