Immediate and delayed hypersensitivity to ceftriaxone, and anaphylaxis due to intradermal testing with other beta-lactam antibiotics, in a previously amoxicillin-sensitized patient

Pricktest als Provokation – schwere anaphylaktische Reaktion auf Hauttests mit Ceftriaxon bei beruflicher Exposition

Es werden zwei Patienten vorgestellt, die wegen eines Asthma bronchiale bei beruflichem Kontakt mit Ceftriaxon abgeklärt wurden. Bei beiden trat innerhalb von Minuten nach Anlegen eines Pricktests mit Ceftriaxon eine adrenalinpflichtige, anaphylaktische Reaktion auf. Systemische Reaktionen auf Hauttests mit Betalaktamantibiotika sind relativ selten, sie können auch bei Patienten mit vorausgegangenen milden Symptomen wie Urtikaria oder beruflichen Kontaktallergien auf Betalaktame auftreten. Als Risikofaktoren werden schwere Anaphylaxien in der Anamnese und ein kurzes Reaktionsintervall genannt. Eine korrekte Durchführung der Hauttests mit Titration und eine adäquate Überwachung sind zu beachten.

The 3 Cs of Antibiotic Allergy-Classification, Cross-Reactivity, and Collaboration

Antibiotic allergy labeling is highly prevalent and negatively impacts patient outcomes and antibiotic appropriateness. Reducing the prevalence and burden of antibiotic allergies requires the engagement of key stakeholders such as allergists, immunologists, pharmacists, and infectious diseases physicians. To help address this burden of antibiotic allergy overlabeling, we review 3 key antibiotic allergy domains: (1) antibiotic allergy classification, (2) antibiotic cross-reactivity, and (3) multidisciplinary collaboration. We review the available evidence and research gaps of currently used adverse drug reaction classification systems, antibiotic allergy cross-reactivity, and current and future models of antibiotic allergy care.

Old dog begging for new tricks: current practices and future directions in the diagnosis of delayed antimicrobial hypersensitivity

PURPOSE OF REVIEW

Antimicrobials are a leading cause of severe T cell-mediated adverse drug reactions (ADRs). The purpose of this review is to address the current understanding of antimicrobial cross-reactivity and the ready availability of and evidence for in-vitro, in-vivo, and ex-vivo diagnostics for T cell-mediated ADRs.

RECENT FINDINGS

Recent literature has evaluated the efficacy of traditional antibiotic allergy management, including patch testing, skin prick testing, intradermal testing, and oral challenge. Although patch and intradermal testing are specific for the diagnosis of immune-mediated ADRs, they suffer from drug-specific limitations in sensitivity. The use of ex-vivo diagnostics, especially enzyme-linked immunospot, has been highlighted as a promising new approach to assigning causality. Knowledge of true rates of antimicrobial cross-reactivity aids empirical antibiotic choice in the setting of previous immune-mediated ADRs.

SUMMARY

In an era of increasing antimicrobial resistance and use of broad-spectrum antimicrobial therapy, ensuring patients are assigned the correct 'allergy label' is essential. Re-exposure to implicated antimicrobials, especially in the setting of severe adverse cutaneous reaction, is associated with significant morbidity and mortality. The process through which an antibiotic label gets assigned, acted on and maintained is still imprecise. Predicting T cell-mediated ADRs via personalized approaches, including human leukocyte antigen-typing, may pave future pathways to safer antimicrobial prescribing guidelines.

Allergic contact dermatitis to topical antibiotics: Epidemiology, responsible allergens, and management

Topical antibiotics are widely used to treat cutaneous, ocular, and otic infections. Allergic contact dermatitis to topical antibiotics is a rare but well-documented side effect, especially in at-risk populations. The purpose of this article is to review the epidemiology, responsible allergens, and management of allergic contact dermatitis to topical antibiotics.

LEARNING OBJECTIVE

After completing this learning activity, participants should be able to describe the epidemiology of allergic contact dermatitis related to topical antibiotics; show knowledge of the most common allergenic topical antibiotics; and understand the allergenic cross-reactivity pattern amongst topical antibiotics.

Nonimmediate reactions to betalactams

PURPOSE OF REVIEW

Nonimmediate reactions to beta-lactams include several clinical entities, from maculopapular rash to severe reactions such as Steven-Johnson syndrome. Toxic epidermal necrolysis and organ-specific reactions may also occur.

RECENT FINDINGS

Progress has been made in understanding the role of the immunological system in nonimmediate reactions to beta-lactams. Different T-cell subsets recognize beta-lactams after haptenation of serum or cell proteins in the context of major histocompatibility complex. Studies using T-cell lines and clones have shown that a heterogeneous response is generated, with the expression of different cytokine profiles. Betalactams also act on dendritic cells, inducing changes that enable them to interact with naïve lymphocytes, becoming memory T cells. Tissue-activated CD4 and CD8 cells express perforin and other cytotoxic mediators that elicit the lesions. Studies on the clinical course of these entities indicate that cells migrate, establishing a recirculation with homing to the skin and back to the circulation. These cells thus participate not only in skin lesions but probably also in the repair process.

SUMMARY

Understanding the immunological mechanisms involved in nonimmediate reactions to beta-lactams has improved over the last few years, with better definition of the different T-cell subpopulations involved. Experimental studies and monitoring of the response support the implication of different cell subsets.

Adverse reactions induced by NSAIDs and antibacterials: analysis of spontaneous reports from the Sicilian regional database

OBJECTIVES

To (i) evaluate the suspected adverse drug reactions (ADRs) related to NSAIDs and antibacterials that were reported to Sicilian local health officers by healthcare professionals; and (ii) to detect new or serious potential signals of alarm related to these two widely used drug categories.

METHODS

We selected all the spontaneous reports of ADRs sent between January 1998 and June 2004 and analysed those attributed to NSAIDs and systemic antibacterials, applying proportional reporting ratio (PRR) methodology. PRRs >2, chi(2) >4 and >3 ADRs were regarded as signals.

RESULTS

During the period considered, 1585 reports of ADRs were received overall (42.6% serious), with an annual reporting rate of approximately 49.1 reports per million inhabitants on average; 351 referred to systemic antibacterials, and 179 to NSAIDs. There were 174 (49.6%) reports of serious ADRs associated with antimicrobials and 108 (60.3%) associated with NSAIDs. Disproportionality was observed, in particular for anaphylactic shock induced by ceftriaxone (all reports were associated with off-label use of the drug), photosensitivity reaction induced by lomefloxacin (administered in the summer), hepatitis induced by nimesulide (three cases leading to liver transplantation) and vasculitis induced by nimesulide.

CONCLUSION

Our analysis highlighted several signals of alarm deserving further investigation or measures to influence prescribing. This study underlines the value of a regional centre in identifying local factors (such as prescribing patterns) that may increase the prevalence of serious ADRs.

Heterogeneity of the IgE response to allergenic determinants of cefaclor in serum samples from patients with cefaclor-induced anaphylaxis

BACKGROUND

Beta-lactam antibiotics, such as cefaclor, may cause IgE-mediated anaphylactic reactions. However, the clinically available serologic test has not been widely accepted, and the antigenic determinants of these drugs are unclear.

OBJECTIVE

To describe 4 cases of anaphylaxis caused by cefaclor in which a specific IgE response to cefaclor was demonstrated.

METHODS

Four patients with anaphylaxis to cefaclor and 35 nonatopic controls never exposed to cefaclor were studied. Skin tests and oral challenges with this drug were performed. The specific IgE response to the antigenic determinant of cefaclor-human serum albumin (HSA) conjugate was compared in each patient. The serum specific IgE to cefaclor-HSA conjugate was detected using enzyme-linked immunosorbent assay (ELISA). Also, ELISA inhibition studies using various concentrations of cefaclor-HSA, HSA alone, and free cefaclor were performed, as were hapten inhibition studies using cefaclor, cephalexin, cefadroxil, ampicillin, ceftriaxone, and cefotaxime.

RESULTS

Three patients showed high levels of serum specific IgE to cefaclor-HSA and marked inhibition patterns to free cefaclor and cefaclor-HSA conjugate on ELISA inhibition testing. Hapten inhibition testing in 3 individual serum samples showed 2 different patterns. In patient 3, significant dose-dependent inhibitions (up to 92%) were noted with additions of free cefaclor and cefaclor-HSA conjugate, and lesser inhibitions (up to 74%) were noted with cephalexin, which shares the aminobenzyl side chain. In patients 1 and 2, marked dose-dependent inhibitions were noted only with additions of cefaclor-HSA conjugate and free cefaclor, whereas minimal inhibitions were noted with the other 5 compounds.

CONCLUSIONS

The specific IgE response to cefaclor-HSA conjugate in patients with cefaclor anaphylaxis occurs against the hapten, in which heterogeneity of the antigenic determinant was noted to depend on the individual.

Cefazolin Tolerance Does Not Predict Ceftriaxone Hypersensitivity: Unique Side Chains Precipitate Anaphylaxis

A 48-year-old woman with a questionable history of an unspecified ceftriaxone allergy was treated with cefazolin for surgical antibiotic prophylaxis. After she tolerated cefazolin therapy for 4 days, the medical staff concluded that her allergy history was inaccurate, and she was treated with intravenous ceftriaxone for suspected nosocomial pneumonia. Approximately 10 minutes after the start of the infusion, the patient experienced anaphylaxis. Initial symptoms of oral angioedema and laryngopharyngeal constriction progressed to dyspnea, tachypnea, hypotension, and tachycardia, all of which quickly resolved after immediate treatment with hydrocortisone, diphenhydramine, and epinephrine. Skin testing with cefazolin, cefepime, and ceftriaxone revealed that the likely allergic determinant mediating the patient's hypersensitivity reaction was the unique ceftriaxone R2 side chain and not the beta-lactam ring, which initially was suspected by the physician. Immunoglobulin E-mediated hypersensitivity reactions to cephalosporins may occur due to antibody complexes with the beta-lactam ring or various cephalosporin side chains. Misconceptions regarding the nature of cephalosporin allergies complicate antibiotic selection for patients with questionable allergy histories and may lead to inappropriate drug reexposure and anaphylaxis. Detailed understanding of the antigenic determinants that mediate hypersensitivity reactions is essential for clinicians to avoid type 1 reactions in patients with a suspected allergy to cephalosporins.