Inappropriate Use of Aztreonam

Area of Science:

• Infectious Diseases
• Clinical Pharmacy
• Allergy and Immunology

Background:

• Aztreonam is not a preferred empiric antibiotic due to variable Gram-negative susceptibilities and lack of Gram-positive activity.
• It requires coadministration with vancomycin for broad coverage, increasing costs and complexity.
• Aztreonam is frequently prescribed to patients with reported penicillin allergies without thorough evaluation.

Purpose of the Study:

• To determine the frequency of inappropriate aztreonam (an antibiotic) use.
• To assess the appropriateness of aztreonam prescribing practices at an academic medical center.
• To identify factors contributing to the overuse of aztreonam in clinical settings.

Main Methods:

• A retrospective chart review was conducted to evaluate aztreonam utilization.
• Appropriateness was determined by assessing documented IgE-mediated allergies and prior beta-lactam tolerance.
• Patient records were analyzed for allergy details and previous reactions to beta-lactam antibiotics.

Main Results:

• 46.7% of aztreonam use was deemed inappropriate.
• Inappropriate use was linked to prior beta-lactam tolerance or lack of documented IgE-mediated response.
• Among patients with documented beta-lactam allergy, many lacked specific reaction details or had non-IgE-mediated responses.

Conclusions:

• Aztreonam should be reserved for patients with confirmed IgE-mediated allergic reactions.
• Interventions like provider education and order reviews are proposed to reduce inappropriate aztreonam use.
• Options such as penicillin skin testing and desensitization should be considered for allergic patients.