The Impact of Penicillin Skin Testing on Aztreonam Stewardship and Cost Savings in Immunocompromised Cancer Patients

Abstract

Objective Reported penicillin allergies result in alternative antimicrobial use and are associated with worse outcomes and increased costs. Penicillin skin testing (PST) has recently been shown to be safe and effective in immunocompromised cancer patients, yet its impact on antimicrobial costs and aztreonam utilization has not been evaluated in this population. Method From September 2017 to January 2018, we screened all admitted patients receiving aztreonam. Those with a self-reported history of possible immunoglobulin E (IgE)-mediated reaction to penicillin were eligible for PST with oral challenge. Results A total of 129 patients were screened, and 49 patients were included and underwent testing. Sixteen patients (33%) had hematologic malignancies and 33 patients (67%) had solid tumors. After PST with oral challenge, 46 patients (94%) tested negative, 1 patient tested positive on oral challenge, and 2 patients had indeterminate results. The median time from admission to testing was 2 days (interquartile range, 1–4). After testing negative, 33 patients (72%) were switched to beta-lactam therapy, which resulted in a total of 390 days of beta-lactam therapy. For identical therapy durations, the direct total antibiotic cost was $15 138.89 for beta-lactams versus $78 331.50 for aztreonam, resulting in $63 192.61 in projected savings. A significant reduction in median days of aztreonam therapy per 1000 patient days (10.0 vs 8.0; P = .005) was found during the intervention period. Conclusions Use of PST in immunocompromised cancer patients receiving aztreonam resulted in improved aztreonam stewardship and significant cost savings. Our study demonstrates that PST with oral challenge should be considered in all cancer patients with reported penicillin allergies.

Beta‐lactam allergies, surgical site infections, and prophylaxis in solid organ transplant recipients at a single center: A retrospective cohort study

“…Optimized BLA status in transplant recipients remains a worthy antimicrobial stewardship goal as beta‐lactams are less toxic and costly than alternative antibiotics 10,30 . While our study did not find an association between reported BLA status and SSI incidence, it did demonstrate substantial antimicrobial utilization in transplant recipients in the first month following transplantion.…”

“…17 Optimized BLA status in transplant recipients remains a worthy antimicrobial stewardship goal as beta-lactams are less toxic and costly than alternative antibiotics. 10,30 While our study did not find an association between reported BLA status and SSI incidence, it did demonstrate substantial antimicrobial utilization in transplant recipients in the first month following transplantion. SOT recipients experience a variety of complications postoperatively, and, as a result of chronic immunosuppression, this population is at a higher risk of infection and often receives more antimicrobials than the general population.…”

Antibiotic allergy labels in immunocompromised populations

“…Additionally, this study found a significant difference in antimicrobial cost savings following penicillin evaluations in this cancer cohort. 19 Efficacy of penicillin allergy evaluations has also been shown in transplant populations (see Table 2). One center performed a retrospective analysis of hematopoietic stem cell transplant recipients who underwent BLA evaluation (inpatient or outpatient ST followed by OC to amoxicillin) as part of their routine pretransplantation evaluation.…”

“…performed ST followed by OC to amoxicillin in a cohort of hospitalized cancer patients (67% solid tumor, 33% hematologic malignancy). Ninety‐four percent were delabeled (4% indeterminate skin test result, 2% delayed rash) 19 . Seventy‐two percent of the cohort was able to switch to beta‐lactam antibiotics post‐intervention, with a subsequent decrease in aztreonam use.…”

Overcoming challenges to removing inappropriate penicillin allergy labels: A quality improvement report

“…A decrease in aztreonam usage is associated with significant cost savings. 8 Removal of inappropriate penicillin allergy labels also facilitates an easier transition to oral antibiotics, a key component of antibiotic stewardship programs that can aid in more timely hospital discharge. 6,9 Although many factors contribute to a patient's length of stay, we did note a decreased median length of stay during the intervention period.…”