Abstract
Background: Acute appendicitis is one of the most common abdominal surgical emergencies worldwide and represents an important burden on modern health systems. The cause of the development of sepsis post appendicectomy is multifactorial. A better knowledge of bacteriology and high-risk factors for septic complications in patients with appendicitis will allow a better selection of empirical and therapeutic antibiotic regimens. Materials and methods: This was a prospective study. A total of 111 patients admitted to Dept. of General Surgery, M.K.C.G. Medical College & Hospital with a provisional diagnosis of acute appendicitis from July 2018 to June 2020 were included in the study. All patients received ceftriaxone, ofloxacin and metronidazole as empirical antibiotics in the perioperative period. The intraluminal swab of the excised appendix was sent for microbiological study, and the excised appendix was sent for histopathological study. Results: Bacteria were isolated from 73 out of 111 samples sent for culture (65.76%). The most common organism cultured was Escherichia coli which accounted for 38 isolates (50%). The perforation rate with Pseudomonas aeruginosa positive culture was highest (45.45%), followed by E. coli (21.05%). A high wound infection rate was associated with E. coli (44.44%), followed by P. aeruginosa (33.33%). Amongst patients who developed post-operative wound infection, 66.67% and 46.67% were resistant to ceftriaxone and ofloxacin, respectively. 100% of patients with intra- peritoneal abscesses were resistant to both empirical antibiotics. Conclusion: E. coli and P. aeruginosa were the commonest organisms associated with complicated appendicitis and postoperative sepsis; they were frequently not covered by empirical antibiotics. Change of empirical antibiotics to a higher spectrum is paramount in such cases and may reduce the incidence of both morbidity and mortality.

Key words: Appendicitis, Intraluminal swab, Bacteriology, Empirical antibiotic