Acute appendicitis is one of the most common acute surgical abdominal emergencies.[4] More than 34,600 cases were treated in UK hospitals in 2006 to 2007. Most cases were in male subjects (30,120) and occurred predominantly in the 15 to 59 year age group. A large majority presented (29,576) as medical emergencies.[5] More than 250,000 appendicectomies are performed each year in the US;[6] however, the incidence is lower in populations where a high-fibre diet is consumed.[7] The overall lifetime risk of developing acute appendicitis is 8.6% for males and 6.7% for females; lifetime risk of appendicectomy is around 12% in males and 23% in females.[8][9] The rate of appendicectomy is around 10 per 10,000 cases per year in the US.[10] This condition is most commonly seen in patients aged between early teens and late 40s. There is a slight male to female predominance (1.3:1).

Risk factors

Known to cause constipation. Patients with appendicectomies have low fibre in their diet compared with controls.[7] However, the theory that this is associated with a higher risk of appendicitis is controversial.[14]

A higher incidence of acute appendicitis in Western society may be related to the living conditions and improved personal hygiene.[15]

A balance of gastrointestinal microbial flora is important for prevention of infection, for digestion, and for providing important nutrients.[16] Frequent use of antibiotics and improved hygienic conditions lead to decreased exposure and/or imbalance of gastrointestinal microbial flora that may eventually lead to a modified response to viral infection and thereby trigger appendicitis.[17]

There is an increased incidence of acute appendicitis in adult patients who smoke every day compared with adults who never smoked.[18]

Use of this content is subject to our disclaimer