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Published on: April 21, 2019
History of penicillin allergy and referral for skin testing: evaluation of a pediatric penicillin allergy testing
Joanne M Langley1, Scott A Halperin, Robert Bortolussi
1joanne.langley@dal.ca
Insights
Many children are misdiagnosed with penicillin allergy. Skin testing in children revealed true penicillin allergy is uncommon, highlighting the need for accurate diagnosis and clear communication to avoid unnecessary antibiotic avoidance.
Area of Science:
- Pediatric Allergy and Immunology
- Clinical Microbiology
- Pharmacology
Background:
- Penicillin allergy is frequently reported in children, often leading to the prescription of broader-spectrum and more costly antibiotics.
- Accurate diagnosis of penicillin allergy is crucial to prevent unnecessary antibiotic use and potential adverse effects.
Purpose of the Study:
- To evaluate the effectiveness and outcomes of a penicillin allergy skin testing program in a pediatric population.
- To determine the prevalence of true penicillin allergy among children with a history of suspected reaction.
Main Methods:
- Children with suspected penicillin allergy underwent a two-stage skin testing protocol (scratch and intradermal) using benzylpenicilloyl-polylysin and penicillin G.
- Negative skin test results were followed by an oral penicillin challenge under observation.
- Successful negative testing resulted in communication to referring physicians and health records to remove allergy warnings.
Main Results:
- Out of 72 children tested, only 4% showed a positive response to intradermal skin testing; no children reacted to oral challenges.
- A significant proportion of children (32%) reported hives, and 68% had other types of rashes, with 96% being generalized.
- In 4% of cases, communication failures meant children remained falsely labeled as penicillin-allergic, impacting antibiotic choices.
Conclusions:
- True penicillin allergy is infrequent in children presenting with suspected reactions.
- Many children are mislabeled as penicillin-allergic, underscoring the importance of accurate diagnostic testing.
- Effective communication of test results to healthcare providers and robust health record management are essential for changing prescribing practices.
Introduction:
Penicillin allergy, commonly reported in children, leads to use of more expensive, broad-spectrum drugs. The results and effectiveness of a skin testing program for immediate hypersensitivity to penicillin in children were studied.
Methods:
Children seen at the IWK Health Centre in Halifax between 1986 and 2000 with a history of suspected penicillin allergy were referred by their family physician or pediatrician. Two-stage skin testing (scratch, intradermal) of benzylpenicilloyl-polylysin and penicillin G sodium, with histamine and saline as positive and negative controls, was carried out. If the test results were negative, an oral challenge was conducted and the child observed for 60 minutes. If no adverse reaction was noted, a letter was sent to the referring physician and to Health Records at the IWK Health Centre, indicating that warning labels should be removed from the chart.
Results:
Of 72 children tested, 32% described their past cutaneous eruption as hives and 68% had other rashes; 96% of rashes were generalized. The mean age at the time of the suspected penicillin allergy was 4.4 years; it was 7.4 years at the time of testing. There was no positive response to the scratch testing, but 4% of children had a positive response to intradermal testing. No adverse responses to oral challenge were observed. Letters confirming negative status were not received in 4% (3 of 69) cases, resulting in ongoing avoidance of penicillins and falsely labelling of the child as penicillin allergic.
Conclusions:
In this referral setting, true penicillin allergy was uncommon, suggesting that many children are incorrectly labelled as penicillin-allergic. Communication of test results to family and care providers and health records administration must be effective if testing is to affect prescribing behaviour.
