Heredity may be a predisposing factor in many cases of appendicitis. According to one study, a child with one or more relatives who had an appendectomy has a risk of appendicitis 10 times that of a child with no family history.
    The family connection can also be explained in part by environmental factors shared by a family: food habits, exposure to a particular bacterial infection and a genetic difference in bacterial resistance.
[SOURCE: Emre Ergul, “Importance of family history and genetics for the prediction of future appendicitis,” The Internet Journal of Surgery, June 28, 2007]

Appendicitis, Cancer Often Co-Exist
                                                                                       

Pain in the lower right part of the abdomen is a classic sign of appendicitis. One recent Taiwan study of appendicitis cases concluded that in patients over age 40, the possibility of co-existent colon cancer was elevated.  “These patients should undergo colonoscopy six weeks after surgery to exclude the possibility of a coexistent colorectal cancer,” the authors wrote.
    Signs of possible colon cancer include weight loss, anemia, a palpable mass and atypical right-sided abdominal pain.
[SOURCE: Hung-Wen Lai, et al, “Incidence and odds ratio of appendicitis as first manifestation of colon cancer: A retrospective analysis of 1873 patients,” Journal of Gastroenterology and Hepatology, December, 2006]

Belly Aches Are Often Serious
                                                                                                              

A persistent belly ache–severe enough to send you to the emergency center–may or may not be appendicitis. But in about 10 percent of cases, it’s a serious condition, according to one study. Appendicitis pain typically starts near the navel and moves to the lower right quadrant. A thorough evaluation by a physician is required for a diagnosis.
    In addition to the abdominal pain, symptoms that may indicate an emergency condition (not necessarily appendicitis) include fever, persistent vomiting, light headedness and fainting.
[SOURCE: Laurie Barclay and Penny Murata, “Evaluation of acute abdominal pain reviewed,” Medscape Medical News CME, April 18, 2008]

How Likely Is It Appendicitis?
                                                                                       

Persistent abdominal pain in an adult can have many possible causes. One study found that only 6 of 556 patients seen for abdominal pain at three family practice centers were diagnosed with appendicitis.
    Among children, on the other hand, studies have found that 10 to 25 percent of patients with abdominal pain had appendicitis.
[SOURCE: Mark H. Ebell, “Diagnosis of appendicitis: part I. History and examination,” American Family Physician, March 15, 2008]