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Published on: August 30, 2018
A prospective observational study of the effect of penicillin skin testing on antibiotic use in the intensive care
Mercedes E Arroliga1, Christine Radojicic, Steven M Gordon
1Allergy Section, The Cleveland Clinic Foundation, Ohio 44195, USA.
Background:
Patients with penicillin allergy admitted to the intensive care unit (ICU) frequently receive non-beta-lactam antimicrobials for the treatment of infection. The use of these antimicrobials, more commonly vancomycin and fluoroquinolones, is associated with the emergence of multidrug-resistant infections. The penicillin skin test (PST) can help detect patients at risk of developing an immediate allergic reaction to penicillin and those patients with a negative PST may be able to use a penicillin antibiotic safely.
Methods:
We determined the incidence of true penicillin allergy, the percentage of patients changed to a beta-lactam antimicrobial when the test was negative, the safety of the test, and the safety of administration of beta-lactam antimicrobials in patients with a negative test. Skin testing was performed using standard methodology.
Results:
One hundred patients admitted to 4 ICUs were prospectively studied; 58 of them were male. The mean age was 63 years. Ninety-six patients had the PST: one was positive (1.04%), 10 (10.4%) were nondiagnostic, and 85 (88.5%) were negative. Of the 38 patients who received antimicrobials for therapeutic reasons, 31(81.5%) had the antibiotic changed to a beta-lactam antimicrobial after a negative reading versus 7 patients of the 57 (12%) who had received a prophylactic antimicrobial (P < .001). No adverse effects were reported after the PST or after antimicrobial administration.
Conclusions:
The PST is a safe, reliable, and effective strategy to reduce the use of non-beta-lactam antimicrobials in patients who are labeled as penicillin allergic and admitted to the ICU.
Insights
The penicillin skin test (PST) safely identifies patients in the ICU who can switch from broad-spectrum antibiotics to safer beta-lactams. This reduces the risk of multidrug-resistant infections in penicillin-allergic patients.
Area of Science:
- Infectious Diseases
- Clinical Pharmacology
- Critical Care Medicine
Background:
- Patients in intensive care units (ICUs) with penicillin allergy often receive non-beta-lactam antimicrobials.
- Use of vancomycin and fluoroquinolones is linked to multidrug-resistant infections.
- Penicillin skin testing (PST) can identify patients safe for penicillin antibiotics.
Purpose of the Study:
- To determine the incidence of true penicillin allergy in ICU patients.
- To assess the safety and efficacy of PST in guiding antimicrobial selection.
- To evaluate the rate of switching to beta-lactam antimicrobials after a negative PST.
Main Methods:
- Prospective study of 100 ICU patients.
- Standardized penicillin skin testing (PST) methodology.
- Analysis of antimicrobial treatment changes based on PST results.
Main Results:
- Only 1.04% of patients had a positive PST.
- 88.5% of patients had a negative PST.
- A negative PST led to a switch to beta-lactams in 81.5% of therapeutically treated patients, with no adverse events.
Conclusions:
- Penicillin skin testing is a safe and reliable method.
- PST effectively reduces non-beta-lactam antimicrobial use in ICU patients with penicillin allergy.
- Implementing PST can help mitigate the emergence of multidrug-resistant infections.
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