SELECTED ARTICLES FROM THE RECENT LITERATURE 2004
12/6/04
Cephalosporin allergy
Summary
Background - Allergic reactions to cephalosporin (Ceph) antibiotics may occur due to sensitization to: 1) their beta-lactam component, a moiety shared with penicillin agents or 2) determinants unique to Ceph agents.
Findings - The subject of Ceph allergy was reviewed by Madaan and Li of the Mayo Clinic in Rochester, MN. They pointed out that individuals with a history of an allergic reaction to penicillin or a Ceph agent may be at increased risk for an allergic reaction to a future treatment with Ceph agents.
Skin testing with a panel of penicillin antigens may be helpful when considering Ceph treatment in someone with a history of a penicillin allergic reaction. Negative findings in such penicillin skin tests indicate that the patient is at no significantly increased risk for an allergic reaction to Ceph. However, skin testing or in vitro IgE antibody tests using Ceph preparations has been of only very limited clinical value.
Reference
Immunol Allergy Clin North Am 2004;24:463-76
Editor's Comments
It is clear that similar beta-lactam moieties are in the central structure of both penicillin and Ceph agents. However, there is still considerable debate about the extent of risk for an allergic reaction to Ceph agents in penicillin- allergic individuals. Part of the uncertainty is the indefinite nature of the previous reactions to penicillin agents described by the patients. Often, the purported allergic reaction happened many years ago in early childhood when a rash occurred several days after a penicillin antibiotic was started for a febrile illness. In some of these cases, the rash may have really been due to the viral infection and not the penicillin treatment. In some cases, penicillin allergy did develop, then remitted after a period of 5-10 years. Thus, rechallenge with Ceph may elicit an allergic reaction in only a small minority of those with histories of "penicillin allergy."
Allergic type reactions to Ceph specific haptenic determinants appear to be a separate problem, not well defined. Use of certain Ceph agents (e.g. Ceclor) is associated with a sizable incidence of delayed onset, serum sickness like reactions. More information is needed.
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