Antibiotic Selection for Suspected Neisseria gonorrhoeae Infection Among Penicillin-Allergic Patients in the Emergency Department

Objectives

While penicillin allergies are commonly reported, their cross-reactivity with beta-lactam antibiotics is minimal. First-line treatment of gonorrheal infections includes a cephalosporin. In emergency department (ED) environments, physicians must consider these potential allergies when selecting antibiotics for a patient with symptoms concerning for sexually transmitted infection (STI).

Methods

A retrospective chart review of adult patients with symptoms concerning for STI presenting to an urban ED from January 2014 through June 2019 was performed. Chart discovery used search terms of “STI”, “STD”, “urethritis”, “vaginitis”, and “gonorrhea”. Information abstracted included patient symptoms, type of care provider, antibiotics prescribed or administered in the ED.

Results

A total of 603 patients met inclusion criteria, of which 31 reported allergies to penicillin antibiotics, and another three reported allergies to cephalosporins. Patients reporting penicillin allergy were less likely to receive a cephalosporin antibiotic (p=0.0081). Patients reporting a non-anaphylactic allergy to penicillin received a cephalosporin at a rate of 92.3%. Patients reporting a penicillin allergy under the care of only an attending physician were less likely to receive a cephalosporin antibiotic compared with those whose care teams included either a resident physician or physician assistant (p=0.00019). Patients reporting a penicillin allergy were more likely to receive alternative antibiotics beyond cephalosporins or azithromycin (p=0.048); the most frequently given additional antibiotics were metronidazole, doxycycline, and levofloxacin.

Conclusions 

Patients with penicillin allergies represent a recurring challenge for ED physicians when faced with antibiotic selection for STI symptoms concerning for gonorrheal infection. Those with penicillin allergies are significantly less likely to receive a cephalosporin antibiotic, though these remain the only universally accepted treatment for gonorrheal infections. These findings highlight the significant need for further physician and public education on allergies and antibiotic selection.

1531. Antibiotic Selection for Neisseria gonorrhoeae among Penicillin Allergic Patients in the Emergency Department

Background

While penicillin (PCN) allergies are commonly reported, their cross-reactivity with beta-lactam antibiotics is minimal. First line treatment of gonorrheal infections includes a cephalosporin (CPH). In an emergency department (ED) environment, physicians must consider potential allergies when selecting antibiotics for a patient with symptoms concerning for sexually transmitted infection (STI).

Methods

A retrospective chart review on adult patients with symptoms concerning for STI presenting to an urban ED from January 2014 through June 2019 was performed. Chart discovery was performed using search terms of “STI”, “STD”, “urethritis”, “vaginitis”, and “gonorrhea”. Information abstracted included patient symptoms, type of care provider, and antibiotics prescribed or administered in the ED. The primary outcome was prevalence of allergy to PCN and CPH in patients evaluated for STI symptoms and secondary outcomes included prescribed antibiotic treatments. Chi-square and Fischer-exact tests were utilized to examine for statistical significance, with p values < 0.05 as statistically significant.

Results

A total of 603 patients met the inclusion criteria, of which 31 reported allergies to PCN, and another 3 reported allergies to CPH. Patients reporting PCN allergy were found to be less likely to receive a CPH antibiotic (p=0.0035). Patients reporting a non-anaphylactic allergy to PCN received a CPH at a rate of 92.3%. Attending physicians in particular were less likely to prescribe a CPH antibiotic to a patient reporting allergy compared with both resident physicians and PAs (p=0.00019). Patients reporting a PCN allergy were more likely to receive alternative antibiotics beyond CPH or azithromycin (p=0.046); the most frequently given antibiotics were metronidazole, doxycycline, and levofloxacin.

Demographic Data

Antibiotic Prescriptions by Type of Penicillin Allergy

Antibiotic Prescriptions for Penicillin Allergy vs. No Allergy

Conclusion

Patients with PCN allergies represent a recurring challenge for ED physicians when faced with antibiotic selection for STI symptoms concerning for gonorrheal infection. Those with PCN allergies are significantly less likely to receive a CPH antibiotic, though these remain the only universal treatment for gonorrheal infections. These findings highlight the significant need for further physician education on allergies and antibiotic selection.

Disclosures

All Authors: No reported disclosures

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