Funding: None Disclosures: Susy Hota reports contract research for Finch Therapeutics. Doi:10.1017/ice.2020.1182 Presentation Type: Poster Presentation Use of a Beta-Lactam Graded Challenge Process at an Academic Medical Center Andrew Watkins, Nebraska Medicine; Lee Amaya, Beaumont Hospital - Royal Oak; Macey Wolfe, Nebraska Medicine; John Schoen, Nebraska Medicine; Erica Stohs, University of Nebraska Medical Center; Sara May, Nebraska Medicine; Mark Rupp, University of Nebraska Medical Center; Trevor Craig Van Schooneveld, University of Nebraska Medical Center; Bryan Alexander, Nebraska Medicine; Scott Bergman, Nebraska Medicine Background: A penicillin allergy guidance document containing an algorithm for challenging penicillin allergic patients with β-lac- tams was developed by the antimicrobial stewardship program (ASP). As part of this algorithm, a “graded challenge” order set was created containing antimicrobial orders and safety medica- tions along with monitoring instructions. The process is designed to challenge patients at low risk of reaction with infusions of 1% of the target dose, then 10%, and finally the full dose, each 30 minutes apart. We evaluated outcomes from the order set. Methods: Orders of the graded challenge over 17 months (March 2018 through July 2019) were reviewed retrospectively. Data were collected on order- ing and outcomes of the challenges and allergy documentation. Use was evaluated based on ASP-recommended indications: his- tory of IgE-mediated or unknown reaction plus (1) no previous β-lactam tolerance and the reaction occurred >10 years ago, or (2) previous β-lactam tolerance, now requiring a different β-lactam for treatment. Only administered challenges were included and descriptive statistics were utilized. Results: Of 67 orders, 57 graded challenges were administered to 56 patients. The most common allergies were penicillins (87.7%) and cephalosporins (38.6%), with the most common reactions being unknown (41.7%) or hives (22%). The most common antibiotics challenged were ceftriaxone (43.9%), cefepime (21.1%), and cefazolin (5.3%). Antibiotics given prior to challenge included vancomycin (48.2%), fluoroquinolones (35.7%), carbapenems (21.4%), aztreonam (19.6%), and clindamy- cin (12.5%). The median duration of challenged antibiotic was 6 days. The infectious diseases service was consulted on 59.6% of challenges and 75.4% of challenges were administered in non- ICU settings. There was 1 reaction (1.8%) involving a rash with the second infusion, which was treated with oral diphenhydramine and had no lasting effects. Based on indications, 80.7% of chal- lenges were aligned with ASP guidance criteria. The most common use outside of these criteria was in patients without IgE-mediated reactions (10.5%). Most of these had minor rashes and could have received a full dose of a cephalosporin. Allergy information was updated in the electronic health record after 91.2% of challenges. Conclusions: We demonstrated the utility of a graded challenge process at our academic medical center. It was well tolerated, ordered frequently by noninfectious diseases clinicians, adminis- tered primarily in non-ICU settings, and regularly resulted in updated allergy information in the medical record. With many patients initially receiving broad-spectrum antibiotics with high costs or increased rates of adverse effects, graded challenges can potentially prevent the use of suboptimal therapies with minimal time and resource investment. Funding: None Disclosures: Scott Bergman reports a research grant from Merck. Doi:10.1017/ice.2020.1183 Presentation Type: Poster Presentation Use of a Multidisciplinary Incident Command System in Response to Measles Outbreak in Maryland Taylor McIlquham, Johns Hopkins Hospital; Anna Sick-Samuels, Johns Hopkins School of Medicine; Carrie Billman, The Johns Hopkins Hospital; Jennifer Andonian, The Johns Hopkins Hospital; Melissa Dudley, The Johns Hopkins Hospital; Amyna Husain, Johns Hopkins University; Robert Maloney, Johns Hopkins Medicine; Cagla Oruc, Johns Hopkins Medicine; Mary Brown, Johns Hopkins Medicine; Lisa Maragakis, Johns Hopkins University School of Medicine; Aaron Michael Milstone, Johns Hopkins University Table 1. Indicators of RVI Transmission Before and After Implementation of Universal Masking Policy on Malignant Hematology Units Indicator Before Implementation After Implementation P Value Nosocomial RVI cases, no. 107 80 N/A Nosocomial RVI a incidence (no. of cases per 1,000 patient days) 2.00 1.11 .033 RVI outbreaks, no. 3 2 N/A RVI cases during outbreaks, no. 23 11 N/A a RVIs included influenza A/B, respiratory syncytial virus, metapneumovirus, and parainfluenza 1–4. Fig. 1. Decennial 2020 Abstracts S502 41 Suppl 1; 2020 Downloaded from https://www.cambridge.org/core. 01 Oct 2021 at 11:34:45, subject to the Cambridge Core terms of use.