Are Cephalosporins Safe for Use in Penicillin Allergy without Prior Allergy Evaluation?

Controversies in Drug Allergy: Drug Allergy Pathways

Drug allergy pathways are standardized approaches for patients reporting prior drug allergies with the aim of quality improvement and promotion of antibiotic stewardship. At the International Drug Allergy Symposium during the 2018 American Academy of Allergy, Asthma, and Immunology/World Allergy Organization Joint Congress in Orlando, Florida, drug allergy pathways were discussed from international perspectives with a focus on beta-lactam allergy pathways and pragmatic approaches for acute care hospitals. In this expert consensus document, we review current pathways, and detail important considerations in devising, implementing, and evaluating beta-lactam allergy pathways for hospitalized patients. We describe the key patient and institutional factors that must be considered in risk stratification, the central feature of pathway design. We detail shared obstacles to widespread beta-lactam allergy pathway implementation and identify potential solutions to address these challenges.

Inpatient β-lactam test-dose protocol and antimicrobial stewardship in patients with a history of penicillin allergy

BACKGROUND

Penicillin allergy is the most commonly reported drug allergy in hospitalized patients, resulting in increased second-line antibiotic use, nosocomial infections, and health care use. Given that most patients are not truly allergic, a safe strategy that empowers the admitting physician is needed.

OBJECTIVE

To assess the effect on antibiotic prescribing practices for hospitalized patients with penicillin allergy using a validated intervention.

METHODS

An intervention was implemented to educate health care professionals on management of patients with penicillin allergy using a validated risk stratification algorithm to guide testing and antibiotic use. Thirty days of control data using current standard of care was compared with 60 days of postintervention data measuring documentation of penicillin allergy history and antibiotic selection.

RESULTS

The relative use of cephalosporin and penicillin antibiotics increased by 121.2% (P = .03) and 256% (P = .04), respectively, without an increase in adverse drug reactions. There was a decrease in the use of broad-spectrum antibiotics: vancomycin, 67.2% (P = .04); quinolones, 33.3% (P = .31); carbapenems, 81.9% (P = .08); and aztreonam, 73.8% (P = .18).

CONCLUSION

The antibiotic choice in patients admitted to the hospital with a reported penicillin allergy can be improved by better evaluation of the allergy history and the use of a risk stratification guideline.

Cross-Reactivity and Tolerability of Cephalosporins in Patients with IgE-Mediated Hypersensitivity to Penicillins

BACKGROUND

Studies performed since 1990 on samples of at least 30 subjects with a documented IgE-mediated hypersensitivity to penicillins have found a rate of positive responses to allergy tests with cephalosporins ranging from 0% to 27%.

OBJECTIVE

We sought to assess the cross-reactivity with cephalosporins and evaluate the possibility of using cephalosporins in penicillin-allergic subjects.

METHODS

We conducted a prospective study of 252 consecutive subjects who had suffered 319 immediate reactions (mostly anaphylaxis) to penicillins and had positive skin tests to at least 1 penicillin reagent. All patients underwent serum specific IgE assays for cefaclor, as well as skin tests with 3 aminocephalosporins (cephalexin, cefaclor, and cefadroxil), cefamandole, cefuroxime, ceftazidime, ceftriaxone, cefotaxime, and cefepime. Patients with negative results for the last 5 cephalosporins were challenged with cefuroxime axetil and ceftriaxone; those with negative results for aminocephalosporins were also challenged with cefaclor and cefadroxil.

RESULTS

Ninety-nine participants (39.3%) had positive allergy tests for cephalosporins. Specifically, 95 (37.7%) were positive to aminocephalosporins and/or cefamandole, which share similar or identical side chains with penicillins. All 244 subjects who underwent challenges with cefuroxime axetil and ceftriaxone tolerated them. Of the 170 patients who underwent aminocephalosporin challenges, 3 reacted to cefaclor and 4 to cefadroxil.

CONCLUSIONS

Cross-reactivity between penicillins and cephalosporins seems to be mainly related to side chain similarity or identity. Subjects with an IgE-mediated hypersensitivity to penicillins could be treated with cephalosporins such as cefuroxime and ceftriaxone that have side-chain determinants different from those of penicillins and are negative in pretreatment skin testing.