TY - JOUR TI - Microbial Epidemiology of Acute and Perforated Appendicitis: A Post-Hoc Analysis of an EAST Multicenter Study AU - Jawad, Khaled Abdul AU - Qian, Sinong AU - Vasileiou, Georgia and AU - Larentzakis, Andreas AU - Rattan, Rishi AU - Dodgion, Chris AU - Kaafarani, AU - Haytham AU - Zielinski, Martin AU - Namias, Nicholas AU - Yeh, D. Dante and AU - EAST Appendicitis Res Grp JO - Journal of Surgical Research PY - 2022 VL - 269 TODO - null SP - 69-75 PB - ACADEMIC PRESS INC ELSEVIER SCIENCE SN - 0022-4804, 1095-8673 TODO - 10.1016/j.jss.2021.07.026 TODO - appendicitis; microbiota; epidemiology; bacteria; antibiotics TODO - Background: There are significant practice variations in antibiotic treatment for appendicitis, ranging from short-course narrow spectrum to long-course broad-spectrum. We sought to describe the modern microbial epidemiology of acute and perforated appendicitis in adults to help inform appropriate empiric coverage and support antibiotic stewardship initiatives. Methods: This is a post-hoc secondary analysis of the Multicenter Study of the Treatment of Appendicitis in America: Acute, Perforated, and Gangrenous (MUSTANG) which prospectively enrolled adult patients (age >= 18 years) diagnosed with appendicitis between January 2017 and June 2018 across 28 centers in the United States. We included all subjects with positive microbiologic cultures during primary or secondary (rescue after medical failure) appendectomy or percutaneous drainage. Culture yield was compared between low-and high-grade appendicitis as per the AAST classification. Results: A total of 3,471 patients were included: 230 (7%) had cultures performed, and 179/230 (78%) had positive results. Cultures were less likely to be positive in grade 1 compared to grades 3, 4, or 5 appendicitis with 2/18 (11%) vs 61/70 (87%) (p < .001). Only 1 subject had grade 2 appendicitis and culture results were negative. E. coli was the most common pathogen and cultured in 29 (46%) of primary appendectomy samples, 16 (50%) of secondary, and 44 (52%) of percutaneous drainage samples. Conclusion: Culturing low-grade appendicitis is low yield. E. coli is the most commonly cul-tured microbe in acute and perforated appendicitis. This data helps inform empiric coverage for both antibiotics alone and as an adjunct to operative or percutaneous intervention. (c) 2021 Published by Elsevier Inc. ER -