Alarming AAA in Infectious Disease: Aztreonam Use, Allergy History and Antimicrobial Stewardship Collide
Background: Penicillin allergy (PA) is reported by 10 % of patients. Fewer than 10% of these have a positive skin test, allergy details are often sparse. Increasing gram negative resistance makes empiric therapy difficult if beta lactam antimicrobials cannot be utilized. Use of alternate agents is associated with higher costs, increased length of stay and other adverse outcomes. Vancomycin is often used with aztreonam (AZ) to provide gram positive coverage, exposing patients to risk of nephrotoxicity. Stewardship team (ST) interventions can mitigate these patient outcome and cost issues.
Methods: Methods: Several stepped interventions were instituted. At our institution, AZ was frequently administered when PA was noted. Annual cost for AZ acquisition reached $360,000 annually. Requiring infectious disease (ID) approval for AZ, we decreased our use by 2/3; subsequently requiring approval directly from the ST with an investigation of allergy and antibiotic use history decreased AZ use a further 2/3 from prior year; then instituting a carbapenem graded challenge for severe or unknown PA decreased use of AZ by 50% again
Results: Results: We evaluated 212 patients between July 1 of 2010 and April 22, 2014 who received at least one dose of Aztreonam. The single most frequent reason for AZ request was PA in the form of rash. In 50% of patients a history of safe beta lactam administration could be documented after review of medical records and beta lactams were utilized. Quinolones were substituted less than 10% of the time. 19 patients underwent a carbapenem graded challenge. No adverse reaction to carbapenem graded challenge was observed even in history of anaphylaxis to penicillin. 12% of AZ requests were appropriate and approved
Conclusion: These interventions have led to a marked decrease in the use of aztreonam in favor of cephalosporin and carbapenem antimicrobials, allowing for annual cost savings of $343,000 and the ability to choose from a wider selection of antibiotic agents. Clarifying PA details and administering monitored carbapenem graded challenges for severe or unknown PA can improve patient care while decreasing costs.
G. Scully, None