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Use of broader spectrum antibiotics in patients with beta-lactam allergies is associated with the development of drug resistant bacteria, including methicillin resistant Staphylococcus aureus (MRSA), and healthcare associated infections such as Clostridium difficile related colitis.
Up to 20% of patients admitted to hospital report an “allergy” to penicillin; however, less than 2% of patients are truly allergic.
Many prior reactions are misclassified as allergy.
Even among those with real documented penicllin allergy, hypersensitivity declines over time rendering the majority of patients (90%) non-allergic after 10 years.
There is no evidence that IgE-mediated reactions are genetically mediated.
Whenever possible, a complete history should be obtained from the patient, primary care physician, or family member to determine the likely nature and cause of the adverse experience with penicillin or beta-lactam.
This detailed information is required to determine whether related (“beta-lactam”) antibiotics can be used or must be avoided since alternative antibiotics may be less effective, more toxic, and associated with poorer outcomes including longer length of stay and increased cost to hospitals. These alternate agents frequently have a broader antimicrobial spectrum and can contribute to the development and spread of antimicrobial resistance.
