Overview of appendicitis
Appendicitis is the most common abdominal emergency with a lifetime occurrence of 7%.
The peak incidence seen between the ages of 10 and 30 years.1 The diagnosis of appendicitis is based primarily on the patient’s history and the physical examination. The most important physical examination finding is right lower quadrant tenderness on palpation. Imaging techniques such as ultrasonography and computed tomography (CT) improve diagnostic accuracy and patient outcomes but their use should be selective in those with atypical presentation.
Accurate and timely diagnosis of acute appendicitis is essential to reduce morbidity. Prompt surgical treatment may reduce the risk of appendix perforation and subsequent complications. Appendicectomy is the treatment of choice and is increasingly done as a laparoscopic procedure.
How appendicitis develops (Pathogenesis of appendicitis)
Obstruction of the narrow appendiceal lumen initiates the development of acute appendicitis. The obstruction may be due to fecaliths, lymphoid hyperplasia (related to viral illnesses such as gastroenteritis), gastrointestinal parasites, foreign bodies and Crohn’s disease.
Continued secretion of mucus from the obstructed appendix leads to increased intraluminal pressure resulting in tissue ischemia, bacterial over-growth, transmural inflammation and possible perforation. Inflammation may extend into the parietal peritoneum and adjacent structures.
Symptoms of appendicitis (Clinical Features of appendicitis)
A typical presentation of acute appendicitis consists of right lower quadrant pain, abdominal rigidity and shifting of pain from the periumbilical region to the right lower quadrant (iliac fossa).2 Loss of appetite, nausea and constipation are often present. Profuse vomiting may indicate development of generalized peritonitis after perforation but is not a common feature in simple appendicitis.
The most important physical finding is right lower quadrant pain on palpation of the abdomen. The site of maximal tenderness is over McBurney’s point, which lies two-thirds along a line drawn from the umbilicus to the anterior superior iliac spine. Other findings include low-grade fever, peritoneal signs and guarding. Unusual presentations occur if the patient is young or elderly, in women of childbearing age and when the appendix is not in its normal location.2
Diagnosis of appendicitis
The overall diagnostic accuracy achieved by history, physical examination and laboratory tests is approximately 80%.2 The accuracy of diagnosis varies by the patient’s sex and age. In atypical cases, ultrasonography and CT may reduce the rate of false-negative diagnoses, reduce morbidity from perforation and lower cost of hospitalization.3
Complications of appendicitis
The most common complication of appendicitis is appendiceal rupture and perforation. Factors that increase the rate of perforation are delayed presentation to medical care, presentation in the children or elderly and hidden location of appendix.1
Management of appendicitis
Appendicectomy remains as the standard management of non-perforated appendicitis and may be performed by laparotomy or laparoscopy. Laparoscopic intervention has the advantages of decreased postoperative pain, earlier return to normal activity and better cosmetic results although the number of intra-abdominal abscesses was higher after the laparoscopic approach.4 Diagnostic laparoscopy may be helpful in equivocal cases or in women of childbearing age. If the patient is unfit for surgical intervention broad-spectrum antibiotics and be given.
1.Hardin DM Jr. Acute appendicitis: Review and update. Am Fam Physician. 1999; 60(7): 2027–2034.
2.Old JL, Dusing RW, Yap W, Dirks J. Imaging for suspected appendicitis. Am Fam Physician. 2005; 71(1): 71–78.
3.Lee SL, Ho HS. Ultrasonography and computed tomography in suspected acute appendicitis. Semin Ultrasound CT MR. 2003; 24(2): 69–73.
4.Sauerland S, Lefering R, Neugebauer EA. Laparoscopic versus open surgery for suspected appendicitis. Cochrane Database Syst Rev. 2004; (4): CD001546.