Mucosal Invasion by Fusobacteria is a Common Feature of Acute Appendicitis in Germany, Russia, and China

Background/Aim: To investigate the geographic occurrence of mucosa-invading Fusobacteria in acute appendicitis. Patients and Methods: Carnoy- and formalin-fixated appendices from Germany, Russia, and China were comparatively investigated. Bacteria were detected using fluorescent in situ hybridization. Cecal biopsies from patients with inflammatory bowel disease and other conditions were used as disease controls. Results: Fusobacteria represented mainly by Fusobacterium nucleation were the major invasive component in bacterial infiltrates in acute appendicitis but were completely absent in controls. The occurrence of invasive Fusobacteria in Germany, Russia, and China was the same. The detection rate in Carnoy-fixated material was 70-71% and in formalin-fixated material was 30-36%. Conclusions: Acute appendicitis is a polymicrobial infectious disease in which F. nucleation and other Fusobacteria play a key role.