Appendicitis, Etiology, Macroscopy, and Histology of
Acute appendicitis is an acute emergency characterized by inflammation of the appendix. It is associated with lumen obstruction and infection. Obstruction is usually due to a fecalith; however, other causes have been described: food fragments, lymphoid hyperplasia (mostly in children), endometriosis, and primary and secondary tumors. Regarding infection, Fusobacteria (F. nucleatum and F. necrophorum) was identified in 62% of patients with acute appendicitis (Swidsinski et al. 2012). Other bacterias (Salmonella, Shigella, C. difficile, Campylobacter), viruses (Adenovirus, CMV, measles, infectious mononucleosis), and parasites (Enterobius vermicularis, Schistosoma, Trichuris, Ascaris, Amoebae, etc.) have been reported. Complications include perforation, peritonitis, periappendiceal abscesses and fibrosis, fistula formation, pylephlebitis with thrombosis of portal venous drainage, and liver abscess formation (Riddell 2014).
References and Further Reading
- Riddell, R. (2014). Appendix. In R. Riddell & D. Jain (Eds.), Lewin, Weinstein, and Riddell’s gastrointestinal pathology and its clinical implications (pp. 806–824). Philadelphia: Lippincott Williams & Wilkins/Walter Kluwer.Google Scholar
- Swidsinski, A., Dörffel, Y., Loening-Baucke, V., Tertychnyy, A., Biche-Ool, S., Stonogin, S., Guo, Y., & Sun, N. D. (2012). Mucosal invasion by fusobacteria is a common feature of acute appendicitis in Germany, Russia and China. Saudi Journal of Gastroenterology, 18, 55–58.PubMedPubMedCentralGoogle Scholar