Penicillin Allergy Management

A 26 year old pregnant femalewith known Group B Streptococcus colonization is admitted for delivery. She has a history of a penicillin allergy. Her parent told her she had a rash as a child but she has no further details .

What GBS prophylaxis should be used?

A) Clindamycin
B) Cefazolin
C) Vancomycin

How did others respond?

Reveal the answer

Best Answer

Cefazolin

Explanation: Given a low risk or non-IgE mediated reaction to penicillin, American College of Obstetricians and Gynecologists (ACOG) guidelines recommend cefazolin as an appropriate alternative for GBS prophylaxis.

WHY?

Though both penicillin and cefazolin fall under the umbrella of beta-lactam antibiotics, their chemical structures are so DISSIMILAR that the risk of cross-reactivity is negligible.

More recently, a 2022 review published in the Journal of Allergy and Clinical Immunology goes even further stating: “…for those rare patients with a history of anaphylaxis to penicillin, a non-cross-reactive cephalosporin (e.g. cefazolin) can be administered routinely." This same review teaches us that cross-reactivity between penicillin and cephalosporin antibiotics is related to side chains rather than the beta-lactam rings. Cephalosporins with DISSIMILAR side chains can be SAFELY given to patients with penicillin allergies