The clinical diagnosis of appendicitis can range from extremely simple to very difficult. More than 10% of planned appendectomies result in the finding of a normal appendix. Additionally, it is far from uncommon that a patient will have appendicitis and progress to perforation while under the care of a physician due to the possibility that the presenting signs and symptoms of appendicitis can mimic many other diseases. Appendicitis has a peak incidence in the third and fourth decades of life but can occur from infancy to old age. The classic presentation of appendicitis includes periumbilical pain spreading to the RLQ as the localized inflammatory process causes peritoneal irritation associated with mild leukocytosis and fever. However, an inflamed retrocecal appendix may present with back pain or ureteric colic and cells in the urine. An inflamed appendix lying within the pelvis may produce pelvic symptoms, and an abscess in this area can result in diarrhea as a result of irritation of the adjacent rectum.

Anorexia is a common presenting symptom with appendicitis and often the patient will complain of nausea. My oldest daughter phoned me from Spain while studying abroad and complained of epigastric pain but maintained her appetite. Despite her atypical presentation and the distance of thousands of miles, we were able to form a presumed diagnosis of appendicitis, which was confirmed at appendectomy a few hours later. There are other times where clinical experience, modern imaging technologies, and laboratory studies fail to confirm the diagnosis and it is only at the time of operation that the diagnosis is confirmed or excluded.

The main diagnostic problem that arises is mistaking other benign conditions for appendicitis. This typically occurs in young women who have right-sided ovarian problems such as rupture of a hemorrhagic ovarian cyst, torsion of an ovarian appendage, endometriosis, hemorrhage into a fibroid, ruptured ectopic pregnancy, or pelvic inflammatory disease. This results in an up to 40% incidence of false-negative appendectomy in young women with RLQ pain. It is in these cases that a laparoscopic exploration may be of greatest benefit. Other conditions that mimic appendicitis are regional adenitis, gastroenteritis in young children, Crohn’s disease, ulcerative colitis, terminal ileitis, urinary tract infection, torsion of an appendix epiploica, diverticulitis of the sigmoid colon lying in the RLQ, perforated duodenal ulcer, or cholecystitis. With such a variety of mimetic conditions, the surgeon may lack adequate access to other parts of the abdomen after having made a muscle-splitting RLQ incision for a mistaken diagnosis of appendicitis. This may even necessitate closing this incision and obtaining access to another part of the abdomen through another celiotomy. In this circumstance the ability to perform a complete exploration of the abdomen using the laparoscope becomes valuable.

Useful diagnostic modalities include a white blood cell count with evidence of increased polymorphonuclear lymphocytes and a radiograph of the abdomen. A fecalith in the appendix, in the presence of RLQ pain and fever, can be diagnostic of acute appendicitis and may be present in up to 10% of cases of appendicitis. Many types of foreign bodies, ranging from seeds of fruit to swallowed materials such as a lead shot, needles, or even a misplaced dental drill bit, have been found within the appendix. A radiograph may reveal ileus of adjacent small bowel loops in the RLQ and the disappearance of the preperitoneal fat line on radiograph as a result of edema in the fatty tissues. Similarly, the right psoas shadow may disappear radiologically because of edema of the retroperitoneal fat surrounding the muscle. In advanced cases, a fluid level from an abscess in the RLQ may be evident. Ultrasound has become valuable in making a diagnosis. The assistance of a skilled and interested radiologist can help in identifying a swollen appendix with surrounding inflammation. It is common for emergency room physicians or referring physicians to order and complete a computed tomography (CT) examination of the abdomen prior to obtaining a surgical consult. CT may be useful in some cases and unnecessary in others. The appendix should measure no more than 6 mm in diameter on CT. Surrounding inflammation or an abscess can be identified. CT has been reported to have an accuracy of 93% and a sensitivity of 98%. The predictive value is greater than 90%. Ultrasonography carries similar good results.

Laparoscopic appendectomy leads to a shortened hospital stay for patients with uncomplicated acute appendicitis, less postoperative pain, faster return to work, and lower total cost of care. The cosmetic benefit is usually significant. Disparities remain relative to when and where patients are offered a laparoscopic approach to appendectomy. Differences have been shown regarding the approach taken with payer mix, gender, and race. Frequently, the most important factor is the surgeon’s preference and skills with laparoscopy. A major advantage with laparoscopy is the ability to carry out a general exploration of the abdominal cavity to exclude other diagnoses. A major disadvantage of the open approach is that the abdominal wound is often left open to avoid wound abscess formation. This can lead to prolonged morbidity and frequent visits for wound care.

Use of the laparoscopic approach hinges on the availability of adequate instrumentation, well-trained assisting personnel in the operating room, and the expertise of the surgeon to carry out the procedure. This should include the ability to tie intracorporeal knots and to carry out safe laparoscopic manipulation of intra-abdominal organs. Unless all of this is available, open appendectomy is preferable. The disadvantage of the laparoscopic approach is that it may lead to an increase in overall cost, depending on the instrumentation and devices used. Early studies demonstrated an increased risk of postoperative abscess after laparoscopic appendectomy when compared with open appendectomy. The rate of abscess formation is now similar in the two approaches and is mostly dependent upon perforation or necrosis of the appendix. In experienced hands the laparoscopic approach allows for better visualization of the abdomen than through a muscle-splitting RLQ incision. Better irrigation of the abdominal cavity can be carried out using several liters of fluid, which can be used to irrigate the entire abdominal cavity under vision.

The patient should be adequately hydrated with a balanced intravenous fluid. Prophylactic antibiotics are given approximately 30 minutes before the surgery. This has been shown to decrease the postoperative inflammatory complication rate. A nasogastric tube may be required in the presence of ileus, generalized peritonitis, or repeated vomiting. A Foley catheter is needed to decompress the bladder.