Abstract

Acute appendicitis is an important pathology in children that requires urgent surgical intervention. Among the many factors that play a role in the pathogenesis of appendicitis, the role of microorganisms is important. In this study, we aimed to isolate bacteria from the appendicitis lumen and pharyngeal swab in children with appendicitis and to perform the molecular analysis of the most common species of bacteria isolated. The swab samples of 76 pediatric patients with suspected appendicitis were taken from the pharynx just before the surgery and from the appendix lumen during the surgery under sterile conditions and inoculated into appropriate media. Virulence gene characterization, molecular analysis, and genotype identification were performed on the most prevalent organism in both appendix and pharynx samples. Three groups were formed as negative appendectomy, complicated appendicitis, and non-complicated appendicitis. The same bacteria were isolated in both the pharynx and appendix lumen in 4 patients in the complicated group and in 2 patients in the non-complicated group. The most commonly isolated bacteria in the appendix lumen was Escherichia coli (E. coli). Highly pathogenic B2 E. coli was found in the appendix, and commensal-growing A phylogroup E. coli was found in the pharynx. We isolated the same type of bacteria in both the pharynx and appendiceal lumen in a significant proportion of patients, especially those with complicated appendicitis. Although they were the same species, they were strains from different genotypes and phylogroups, except for one. Bacteria isolated from the appendix lumen had more pathogenicity and virulence. We think that the reason for the isolation of bacteria not found in normal throat flora in complicated patients may be the deterioration of general body resistance. Therefore, for patients who are found to be complicated during surgery, the early addition of antibiotics effective against highly pathogenic, resistant strains of E. coli may be beneficial.

Key words: Appendicitis, appendix, pharynx, molecular analysis, Escherichia coli