Appendicitis is primarily caused by a blockage of the hollow portion in the appendix.[10] This blockage typically results from a faecolith, a calcified "stone" made of feces.[6] Some studies show a correlation between appendicoliths and disease severity.[11] Other factors such as inflamed lymphoid tissue from a viral infection, intestinal parasites, gallstone, or tumors may also lead to this blockage.[6] When the appendix becomes blocked, it experiences increased pressure, reduced blood flow, and bacterial growth, resulting in inflammation.[6][12] This combination of factors causes tissue injury and, ultimately, tissue death.[13] If this process is left untreated, it can lead to the appendix rupturing, which releases bacteria into the abdominal cavity, potentially leading to severe complications.[13][14]
The diagnosis of appendicitis is largely based on the person's signs and symptoms.[12] In cases where the diagnosis is unclear, close observation, medical imaging, and laboratory tests can be helpful.[4] The two most commonly used imaging tests for diagnosing appendicitis are ultrasound and computed tomography (CT scan).[4] CT scan is more accurate than ultrasound in detecting acute appendicitis.[15] However, ultrasound may be preferred as the first imaging test in children and pregnant women because of the risks associated with radiation exposure from CT scans.[4] Although ultrasound may aid in diagnosis, its main role is in identifying important differentials, such as ovarian pathology in females or mesenteric adenitis in children.
The standard treatment for acute appendicitis involves the surgical removal of the inflamed appendix.[6][12] This procedure can be performed either through an open incision in the abdomen (laparotomy) or using minimally invasive techniques with small incisions and cameras (laparoscopy). Surgery is essential to reduce the risk of complications or potential death associated with the rupture of the appendix.[3]Antibiotics may be equally effective in certain cases of non-ruptured appendicitis,[16][7][17] but 31% will undergo appendectomy within one year.[18] It is one of the most common and significant causes of sudden abdominal pain. In 2015, approximately 11.6 million cases of appendicitis were reported, resulting in around 50,100 deaths worldwide.[8][9] In the United States, appendicitis is one of the most common causes of sudden abdominal pain requiring surgery.[2] Annually, more than 300,000 individuals in the United States undergo surgical removal of their appendix.[19]
^"appendicitis". Medical Dictionary. Merriam-Webster. Archived from the original on 2013-12-30.
^Ferri FF (2010). Ferri's differential diagnosis: a practical guide to the differential diagnosis of symptoms, signs, and clinical disorders (2nd ed.). Philadelphia, PA: Elsevier/Mosby. pp. Chapter A. ISBN978-0-323-07699-9.
^Pieper R, Kager L, Tidefeldt U (1982). "Obstruction of appendix vermiformis causing acute appendicitis. An experimental study in the rabbit". Acta Chirurgica Scandinavica. 148 (1): 63–72. PMID7136413.
^ abSchwartz's principles of surgery (9th ed.). New York: McGraw-Hill, Medical Pub. Division. 2010. pp. Chapter 30. ISBN978-0-07-154770-3.
^Barrett ML, Hines AL, Andrews RM (July 2013). "Trends in Rates of Perforated Appendix, 2001–2010"(PDF). Healthcare Cost and Utilization Project (HCUP) Statistical Brief #159. Rockville, MD: Agency for Healthcare Research and Quality. PMID24199256. Archived(PDF) from the original on 2016-10-20.