Risk Assessment of Immediate Systemic Reactions from Skin Tests with β-Lactam Antibiotics

Abstract

Background: Some clinical studies have demonstrated that skin tests for β-lactam antibiotics may cause more adverse reactions than skin tests for common allergens. Objective: To assess the risk of systemic reactions from penicillin skin testing, based on a pre-test categorization of patients, in order to establish an appropriate strategy for preempting and dealing with cases. Methods: A case series of 175 patients with a suspected allergy to penicillin was reviewed, and patients were classified as having a low or high probability of allergic sensitization to penicillin, according to their clinical history. For every group, the rate and the increase in the relative risk (RRI) of systemic reactions by skin testing were calculated. The results were compared to those reported in the available literature. Results: In our case series of 175 patients, 52 were classified as having a high probability of being allergic to penicillin, according to their clinical history. Five systemic reactions to skin testing were observed, and these were exclusively in this group (9.61%, RRI = 479). In agreement with the literature, patients with a high likelihood of penicillin allergy showed an increase of up to 10% in the occurrence of systemic reactions at skin testing; in patients who had had severe allergic reactions, this figure was up to 20%. Conclusions: The RRI of systemic reactions by skin testing is proportional to the pre-test probability of a true immediate hypersensitivity reaction to β-lactam antibiotics. In the present case series, only patients with high pre-test probability were at risk, and this group should therefore be skin tested and monitored in a hospitalization regimen, where resuscitation staff and access to an emergency room are immediately available.

Penicillin allergy

“…Various groups, including mine previously, have also used amoxicillin, at widely varying concentrations, for skin testing, from about 2 mg/ml or 0.01 molar up to 20 mg/ml, as a minor determinant for skin testing [5,8,13]. The higher amoxicillin concentrations used for skin testing have been associated with higher rates of systemic reactions during skin testing [14][15][16].…”

Anti-Amoxicillin Immunoglobulin E, Histamine-2 Receptor Antagonist Therapy and Mast Cell Activation Syndrome Are Risk Factors for Amoxicillin Anaphylaxis

“…skin prick tests (SPTs) and intradermal tests (IDTs) with penicillin reagents, according to European Network of Drug Allergy protocols [14,15] . In the case of severe anaphylaxis, in vitro tests were considered the only diagnostic choice in order to avoid the risk of severe reactions by skin testing as recently shown [17] . For all the selected patients, statistical analysis was used to evaluate the association between the risk of severe AX-induced reactions and atopy, age, gender, anti-β-lactam IgE levels, dyslipidemia, atherosclerosis, the use of histamine-2 receptor antagonists (anti-H2), proton-pump inhibitors (PPIs) and serum angiotensinconverting enzyme (ACE) therapy, levels of serum ACE and basal serum tryptase and the signs and symptoms of MCAS.…”

Penicillin Therapy in Children with Acute Rheumatic Fever: Side Effects, Malpractice and Anaphylactic Reactions

“…Penisilin allerjisi öyküsünde ile yapısal benzerlik gösterdikleri için sefalosporinler de dikkatli kullanılması gereken ilaçlardır. Majör ve minör determinantlar dışında daha az olarak farklı yapıda olan R grup yan zincirlerine ve beta laktam halkasına karşı da alerjik reaksiyonlar görülebilir (45). Penisilin alerjisinin beta laktam halkasına karşı olması durumda çapraz reaksiyon ciddi bir sorun olur.…”