Acute appendicitis is caused by bacterial infections in the vermiform appendix, a tubular extension of the large intestine which functions as part of the digestive process. When the appendix is blocked by feces or it is squeezed by lymph nodes, it swells and usually doesn’t receive enough blood.

When this happens, bacteria invade and grow inside the appendix, eventually causing its death. Acute appendicitis is serious and can lead to complications like perforation, gangrene and sepsis. A surgical emergency is the only way to remove it but what usually happens is that most patients already have complications before they enter the operating room.

Symptoms of acute appendicitis are intense, continuous abdominal pains, which first occur in the umbilical region and later locate in the right lower region of the abdomen. Other symptoms include poor appetite, nausea, vomiting, constipation or diarrhea, and fever. Although unspecific in character, the symptoms, if they occur often enough, can indicate the presence of the illness.

It is often hard to diagnose appendicitis in young children, the elderly, and women of childbearing age. In kids two years old or younger, the symptoms are vomiting, a bloated or swollen abdomen and pain. In most cases, true appendicitis is often misdiagnosed as gastroenteritis, an inflammation of the stomach and intestines.

It is not uncommon, however, for patients to have only one symptom or without symptoms at all, which complicates the process of correctly diagnosing the illness. The only effective means of discovering acute appendicitis are abdominal computerized tomography, blood analysis and a detailed physical examination.

Surgery remains the first option in the treatment of acute appendicitis. Though a doctor may prescribe treatment with antibiotics to deal with the inflammation and bacterial infection of the appendix, the obstruction can only be corrected through surgical intervention. Called an appendectomy, surgery is the best way to contain the illness and to prevent its recurrence and the development of complications.

Other cures also include using home-made remedies, which is applicable if the appendicitis is caught in its earliest stages and before a rupture occurs. Some of these remedies include fasting, bed rest, applying hot compresses to the painful area several times a day to relieve cramping and inflammation, using an enema daily to help cleanse the lower bowels, and drinking fresh, natural fruit and vegetable juices.

If treated in time, patients suffering from acute appendicitis recover quickly and without effort. Full recover is usually within four weeks from surgery. In the case of complicated acute appendicitis, patients require special monitoring before and long after the surgical treatment.

If undetected and not prevented in time, acute appendicitis is life-threatening with the rate of mortality considerably high.

The operation proceeds much as McBurney first described it in 1894 in treatment of appendicitis. The incision is carried down through the subcutaneous tissue, exposing the aponeurosis of the external oblique muscle, which is divided, either sharply or with electrocautery, in the direction of its fibers . A muscle-splitting technique is typically used, in which the external oblique, internal oblique, and transversus abdominis muscles are separated along the orientation of their muscle fibers. The peritoneum is thus exposed, grasped with forceps, and opened sharply along the orientation of the incision, taking care not to injure the underlying abdominal contents. Hemostats can be placed on the peritoneum to facilitate its identification at the time of wound closure. Cloudy fluid may be encountered on entering the peritoneum. Although some advocate bacterial culture of the peritoneal fluid, studies show that this neither helps direct the antibiotic regimen nor reduces infectious complications.

With a correctly placed incision, the cecum will be visible at the base of the wound. The incision should be explored with a finger in an attempt to locate the appendix. If the appendix is palpable and free from surrounding structures, it can be delivered into the incision. Frequently, the appendix is palpable but it adheres to surrounding structures. Filmy adhesions can be divided using blunt dissection, but thicker adhesions should be divided under direct vision. To facilitate this, the cecum can be partially delivered into the incision to provide better exposure of the appendix. If necessary to improve exposure, the incision can be extended medially by partially dividing the rectus muscle, or laterally by further dividing the oblique and transversus abdominis muscles. If the appendix cannot be visualized, it can be located by following the teniae coli of the cecum to the cecal base, from which the appendix invariably originates. Once located, the appendix is delivered through the incision. Grasping the mesentery with a Babcock clamp can sometimes facilitate this maneuver. Care should be taken to avoid perforation of the appendix, with spillage of pus or enteric contents into the abdomen.

The arterial supply to the appendix, which runs in the mesoappendix, is now divided between clamps and tied with 3-0 polyglactin suture. This is usually performed in an antegrade fashion, from the appendiceal tip toward the base. Division of the artery to the appendiceal base is necessary to ensure that the entire appendix can be removed without leaving an excessively long appendiceal stump.

In excising the appendix, the surgeon must decide whether or not to invert the appendiceal stump. Traditionally, the appendix was ligated and divided, and its stump was inverted with a purse-string suture for the theoretical purpose of avoiding bacterial contamination of the peritoneum and subsequent adhesion formation. However, recent prospective studies show no advantages to appendiceal stump inversion. In one such study, appendectomy patients were randomly assigned to ligation plus inversion or simple ligation of the appendiceal stump. There was no difference between the two groups in the incidence of wound infection or adhesion formation, and operating time was shorter in the simple ligation group. Inversion may also have the deleterious effect of deforming the cecal wall, which could be misinterpreted as a cecal mass on future contrast radiographs. Furthermore, the long-standing notion that stump inversion reduces postoperative adhesions was discredited by Street and colleagues.In their analysis, postoperative adhesions requiring operation were significantly increased in the inversion group.

To divide the appendix, the surgeon can use either suture ligation or a gastrointestinal stapler. For ligation, two hemostat clamps are placed at the base of the appendix. The clamp closest to the cecum is removed, having crushed the appendix at that site. Two heavy, absorbable sutures such as 0 chromic gut is used to doubly ligate the appendix, and the appendix is subsequently divided proximal to the second clamp. The exposed mucosa of the appendiceal stump can be cauterized to minimize the theoretical risk of postoperative mucocele, although no data exist to support this. If appendiceal stump inversion is chosen, a seromuscular purse-string 3-0 silk suture is placed in the cecum around the appendiceal base after ligation but prior to division of the appendix. The purse-string suture should be placed approximately 1 cm from the base of the appendix, as placing it too close to the appendix makes stump inversion difficult. After the appendix is divided, the purse-string suture is tightened and tied while the assistant uses forceps to invaginate the appendiceal stump. Alternatively, the appendix can be divided at its base using a TA-30 stapler. Again, the stump need not be inverted, but can be if desired, using interrupted Lembert sutures with 3-0 silk suture. No matter how the appendix is divided, the residual appendiceal stump should be no longer than 3 mm to minimize the possibility of stump appendicitis in the future.

Occasionally, inflammation at the tip of the appendix makes antegrade removal of the appendix difficult. In such cases, the appendix can be removed in a retrograde fashion. In so doing, the appendix is divided at its base using one of the methods described previously. The mesoappendix is then divided between clamps, starting at the appendiceal base and progressing toward the tip

In certain cases, the appendiceal inflammation extends to the base of the appendix or beyond to the cecum. Division of the appendix through inflamed, infected tissue leaves the potential for leakage of cecal contents with a resultant abscess or fistula. Ensuring that the resection margin is grossly free of active inflammation can minimize this risk. If the base of the cecum is also inflamed but there is sufficient uninflamed cecum between the appendix and the ileocecal valve, an appendectomy with partial cecectomy can be performed using a stapling device.Care should be taken to avoid narrowing the cecum at the ileocecal valve. If the inflammation extends to the ileocecal junction, an ileocectomy with primary anastomosis may be necessary.

After the appendix is removed, hemostasis is achieved and the right lower quadrant and pelvis are irrigated with warm saline. The peritoneum is closed with a continuous 0 absorbable suture; this layer provides no strength but helps to contain the abdominal contents during abdominal wall closure. The internal and external oblique muscles are then closed in succession using continuous 0 absorbable suture. To decrease postoperative narcotic requirements, the external oblique fascia can be infused with local anesthetic. Interrupted absorbable sutures are typically placed in Scarpa’s fascia, and the skin can be closed with a subcuticular absorbable suture. With a preoperative dose of intravenous antibiotics and primary closure of the skin, fewer than 5% of patients with nonperforated appendicitis can be expected to develop a wound infection.

(1) OA can be performed more quickly;

(2) LA patients have less postoperative pain and reduced narcotic requirements;

(3) there is a trend toward reduced length of stay with LA;

(4) LA patients have fewer wound infections;

(5) OA patients develop fewer intra-abdominal abscesses;

(6) LA patients return to work more quickly;

(7) operating room and hospital costs are less with OA; and

(8) societal costs may be less with LA.

Based on the data available, one cannot convincingly recommend either OA or LA over the other. Each method has its advantages and disadvantages that should be considered when deciding how to perform appendectomy.

One situation in which laparoscopic appendectomy may be advisable is when the diagnosis of appendicitis is in doubt. This can be particularly useful in women of childbearing age, in whom obstetric and gynecological pathology may also be likely. In this population, a normal appendix can be found in more than 40% of patients with suspected appendicitis. Laparoscopy can thus be both diagnostic and therapeutic, and a laparotomy can be avoided if gynecologic pathology is found. The ovaries, fallopian tubes, and uterus can be examined for nonappendiceal causes of abdominal pain, including ovarian cyst or torsion, endometriosis, or pelvic inflammatory disease. Laparoscopy makes this evaluation considerably easier and less morbid for the patient. In one study, when a normal appendix was discovered, gynecological pathology was found in 73% of women explored laparoscopically, but only 17% of women who had an open appendectomy. Although diagnostic accuracy will likely improve in young women with more widespread use of CT scans, this population will continue to provide diagnostic dilemmas that may be aided by laparoscopy.

Intravenous antibiotics have been shown to reduce significantly the incidence of postoperative wound infection and intra-abdominal abscess. Antibiotics should be administered 30 minutes prior to incision to achieve adequate tissue levels. The typical flora of the appendix resembles that of the colon and includes gram-negative aerobes (primarily Escherichia coli) and anaerobes (Bacteroides spp.). No standardized antibiotic regimen exists. Acceptable options include a second-generation cephalosporin or a combination of antibiotics directed at gram-negatives and anaerobes. In nonperforated appendicitis, a single preoperative dose of cefoxitin suffices. In cases of perforation, an extended course of at least 5 days of antibiotics is advocated.

Appendicitis in patients with human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) presents unique challenges. Abdominal pain is not an uncommon symptom in these patients, making differentiation between surgical and nonsurgical causes difficult. Nonetheless, immunocompromised patients with appendicitis present with symptoms similar to those of the general population, and appendicitis should be considered in patients with right lower quadrant pain, nausea, and anorexia. Fever and white blood cell count may not be helpful in this population, so imaging studies, particularly CT, have been supported by some authors.There is no specific contraindication to operation in immunocompromised patients, so once diagnosed with appendicitis, appendectomy should be performed promptly.

Appendix

The appendix is a closed, narrow tube up to several centimeters in length that attaches to the cecum (the first part of the colon) like a worm. (The anatomical name for the plant, ie vermiform, worm-like appendage.) The inner lining of the plant produces a small amount of mucus is flowing through the open center of the plant and in the appendix. The wall of the appendix contains lymphatic tissue that is part of the immune system to produce antibodies. As theRest of the colon, the wall of the annex includes a layer of muscles, but the muscle is poorly developed.

Appendicitis Appendicitis means inflammation of the plant. It is thought that appendicitis begins when the opening is blocked from the appendix in the cecum. The blockage may be caused by accumulation of mucus within the appendix or to stool that enters the plant from the appendix. The mucus or stool hardens, as is rock and block the opening. This rock isfecalith called (literally, a rock of stool). At other times, the lymphatic tissue to swell and block the attachment can the plant. After the blockage occurs, bacteria that are normally found in the annex to begin (infect) penetrate the wall of the plant. The body reacts to the invasion of mounting an attack on the bacteria, as an attack inflammation. An alternative theory for the cause of appendicitis is followed by a first fraction of the plant by the spread of bacteria outsideAppendix .. The cause of such a rupture is unclear, but it can lead to changes in the lymphatic tissue, inflammation, for example, that there will be the wall of the plant cover line.)

If the inflammation and the spread of infection through the wall of the appendix, the plant can be broken. After breaking an infection can spread into the abdomen, but usually it is a small neighborhood of the plant is limited (formation of a peri-appendiceal abscess).

Sometimes the body is successfulcontaining ( “healing”) the appendicitis without surgical treatment, if not spread the infection and accompanying inflammation in the stomach. May disappear, the inflammation, pain and symptoms. This applies especially in elderly patients and used for antibiotics. The patient can then come to the doctor long after the episode of appendicitis with a lump or a tumor in the right lower abdomen, the result of scarring that occurs during healing. This package could increaseSuspicion of cancer.

Symptoms

The main symptom of appendicitis abdominal pain. The pain is at first diffuse and poorly localized, which is not confined to one location. (Bad localized pain is typical when a problem is confined to the small intestine and large intestine, including the annex). The pain is so difficult to grasp when asked to enter the field of pain point that most people of the city pain with a circular motion of her hand around the central part of theirStomach. A second, common, early symptom of appendicitis is loss of appetite, nausea and even progress to vomiting. Nausea and vomiting can also occur later by intestinal obstruction.

As an appendix inflammation increases, it extends through the system known to its outer shell and then to the lining of the stomach, peritoneum, a thin membrane. Once ignited, the peritoneum, the pain changes and then clearly localized to a small area. In general, this areabetween the front of the right hip bone and the navel. The exact point is named after Dr. Charles McBurney – McBurney’s point. If the system ruptures and infection spreads into the abdomen, the achiness rekindled as the entire lining of the stomach is.

Diagnosis

The diagnosis of appendicitis begins with a thorough history and physical examination. Often the patients have an elevated temperature, and it is usually in moderate to severe tendernessright lower abdomen when the doctor pushes there. If inflammation has spread to the peritoneum, there is often pain on pressure. Pressure pain is pain that is worse when the doctor quickly release his hand after gently pressing on the abdomen over the area of tenderness.

Number of white blood cells

The number of white blood cells in the blood is increased in general with an infection. Early appendicitis, before infection begins, it may be normal, but most often it is at least oneslight increase also early. Unfortunately, appendicitis is not the only condition that causes elevated white blood cell count. Almost any infection or inflammation, this can lead to unusually high count. Therefore, an increased number of white blood cells alone can not be used as a sign of appendicitis.

Urinalysis

Urinalysis is a microscopic examination of the urine that detects red blood cells, white blood cells and bacteria in the urine. Urinalysis usually is abnormal when itInflammation or stones in the kidneys or bladder. The urinalysis is abnormal with appendicitis because the facility is located near the urethra and bladder. If the inflammation of appendicitis is large enough, it can be to the ureters and bladder that is abnormal urinalysis. Most patients with appendicitis, however, have a normal urinalysis. Therefore, a normal urinalysis suggests appendicitis more than a urinary tract problem.

Abdominal X-Ray

A normal x-ray can detect thefecalith (the hardened and calcified, pea-sized piece of stool blocking the opening Appendix) that the cause may be appendicitis. This is especially true in children.

Ultrasound

An ultrasound scan is a painless procedure that uses sound waves to identify organs in the body. Ultrasound can identify an expanded facility or an abscess. Nevertheless, during appendicitis, the system can be observed in only 50% of patients. Therefore, a look at an ultrasound system is notAppendicitis ruled out. Ultrasound is also useful for women because it ensures the presence of conditions that can, the ovaries, fallopian tubes and uterus that can mimic appendicitis are excluded.

Barium Enema

A barium enema is an x-ray test where liquid barium is introduced into the colon from the anus to fill the bowel. This test may from time to time, show an impression on the colon in the vicinity of the plant where the inflammation from the adjacent meets inflammation of the colon. Barium alsoexclude other intestinal problems that simulate appendicitis, such as Crohn’s disease.

Computed tomography (CT)

For patients who are not pregnant, a CT scan of the area of the plant is in diagnosing appendicitis and peri-appendiceal abscesses as well as the exclusion of other diseases in the abdomen and pelvis, which mimic appendicitis useful.

Laparoscopy

Laparoscopy is a surgical procedure, introduced in which a small fiberoptic tube with a camera into the abdomen througha small hole made in the abdominal wall. Laparoscopy allows a direct view of the plant, and other abdominal and pelvic organs. If appendicitis is found, the inflamed appendix with the laparascope be removed. The disadvantage of laparoscopy compared to ultrasound and CT is that it requires a general anesthetic.

There is no test that will diagnose appendicitis with certainty. Therefore, the approach to suspected appendicitis may include a period of observation, testsmentioned, or surgery.

Treatment

Once the diagnosis of appendicitis is an appendectomy operation is usually performed. Antibiotics started before surgery and almost always as fast as a suspected appendicitis.

There is a small group of patients in whom the inflammation and infection of appendicitis remain mild and localized to a small area. The body is able to not only contain the inflammation and infection, but to solve it as well. These patients are usually not very ill, andImprove during several days of observation. This type of appendicitis is referred to as “confined appendicitis” and may be treated with antibiotics alone. The plant can not or will not be removed at a later date.

Occasionally, a person can not see their doctor until appendicitis with rupture has been present for many days or even weeks. Formed in this situation, usually has an abscess, and perforation of the appendix have signed on. If the abscess is small, can initially be treatedwith antibiotics, but the abscess usually requires drainage. A drain (a small plastic or rubber tube) usually is inserted through the skin and into the abscess using an ultrasound or CT scan that can determine the exact location of the abscess. The drain allows pus from the abscess to flow from the body. The plant can be removed several weeks or months after the abscess has resolved. This will is called an interval appendectomy and done to prevent a second attackAppendicitis.

Surgical Intervention: Appendectomy

During an appendectomy, an average of two to three centimeters in length is made through the skin and the layers of the abdominal wall in the area of the plant. The surgeon enters the abdomen and looks for the plant, which is usually in the right lower abdomen. After examining the vicinity of the plant to be sure that no additional problem is present, is removed the plant. This is done by the liberation of the plant its mesentericAttachment to the stomach and colon, cutting the plant from the colon and sewing over the hole in the colon. If an abscess is present, the pus can be drained with drains that the transfer of abscesses and out through the skin. The abdominal incision is then closed.

Newer techniques for the removal of the facility is through the use of the laparoscope. The laparoscopy is attached to a thin, telescope, video camera, which the surgeon can inspect the inside of the abdomen through a small incision toWound (instead of a larger incision). If appendicitis is found, the facility with special instruments that can be passed into the abdomen, as well as laparoscopy are removed through small puncture wounds. The advantages of the laparoscopic technique are less postoperative pain (since much of the post-operative pain comes from incisions) and a faster return to normal activities. Another advantage of laparoscopy is that it allows the surgeon into the abdomen to look intoclear diagnosis in cases where the diagnosis of appendicitis is in doubt. For example, laparoscopy is especially helpful during menstruation women whose ovarian cysts can mimic a fracture of appendicitis.

If the appendix is not perforated (perforated) at the time of surgery, the patient usually house is from the hospital after the operation in sending one or two days. Patients whose facility with perforated are sicker than patients without perforation, and their hospital stay is often prolonged(four to seven days), especially if peritonitis occurs. Intravenous antibiotics in the hospital given to fight infection and assist in resolving any abscess.

Occasionally, the surgeon can find a normal-appearing facility and no other cause for the problem of the patient. In this situation, the surgeon can remove the plant. The reasoning in these cases is that it is better to remove miss a normal-appearing as an investment and not to treat appropriately an early or mild case ofAppendicitis.

In children with an equivocal history and physical examination, CT has been shown to be highly accurate in diagnosing appendicitis. Garcia Pena and associates compared ultrasonography and rectal contrast CT in 139 children with suspected appendicitis and found CT to be more sensitive (97% for CT, 44% for ultrasound), more specific (94% for CT, 93% for ultrasound), and more accurate (94% for CT, 76% for ultrasound). CT correctly changed the management of 73% of patients, while ultrasound correctly changed 19%. The use of CT can be recommended for children with one caveat. The radiation from a CT in childhood theoretically causes a small increase in the lifetime risk of certain cancers.Therefore, clinicians should consider the risks and benefits of CT, and efforts should be directed toward reducing radiation dose when imaging children.

In the first and early second trimesters, the presentation of appendicitis is similar to that seen in nonpregnant women. In the third trimester, women may not present with right lower quadrant pain due to displacement of the appendix by the gravid uterus. Baer and associates performed barium enemas on normal pregnant women and found the appendix to migrate superiorly towards the right upper quadrant in later stages of pregnancy. His findings suggest that appendicitis should present with right upper quadrant or flank pain in late pregnancy. Two retrospective studies contradict this, however, showing that even in the third trimester, pain and tenderness are more common in the right lower than the right upper quadrant. Nonetheless, right upper quadrant pain did predominate in some third-trimester patients with appendicitis in each study, reminding the clinician that right upper quadrant and right flank symptoms could be due to appendicitis in an appendix displaced by the gravid uterus.

Ultrasound is accurate in pregnancy and is a useful first radiological study because it has no known adverse fetal effects. Rectal contrast CT has also been shown to be highly accurate in the pregnant population. Although ionizing radiation has risks to the fetus, the radiation from a typical abdominopelvic CT is below the threshold of 5 rads at which teratogenic effects are seen.When the diagnosis is in doubt, the risk of radiation should be weighed against the risk of spontaneous abortion from an unnecessary laparotomy or from undiagnosed appendicitis progressing to perforation. Hospital admission with close observation for progression of symptoms is a viable alternative if the risks of radiation from CT scan are deemed excessive.

The pregnant patient should proceed directly to appendectomy if appendicitis is suspected. A normal appendix is not an uncommon finding, as negative laparotomy has been reported in approximately one-third of cases due to the difficulty of diagnosis in this population.Negative laparotomy should not be considered an error in diagnosis, because the risk to the fetus varies directly with the severity of appendicitis. In one series, fetal loss occurred in only 1 (3%) of 30 negative laparotomies. Fetal mortality rises to 5% in cases of nonperforated appendicitis, and increases to 20% when the appendix perforates. These data warrant an aggressive approach to appendectomy. Early negative exploration is justified to minimize the likelihood of progression to perforation.

Although laparoscopic appendectomy has become increasingly popular, its appropriateness during pregnancy remains in question. The gravid uterus can make laparoscopic visualization difficult, particularly if the appendix is located in the pelvis. In addition, carbon dioxide insufflation of the abdomen results in fetal hypercarbia and decreased placental blood flow, the effects of which have not been completely studied. Although case series of successful laparoscopy during pregnancy have been presented, the overall safety of laparoscopic appendectomy in pregnancy is uncertain. Until further research is available, the open approach is advised.

In middle-aged and older adults, other inflammatory conditions should be considered, including peptic or duodenal ulcer (with fluid tracking into the right paracolic gutter), cholecystitis, and pancreatitis. In addition, cecal or sigmoid diverticulitis can be confused with acute appendicitis. Cecal diverticulitis is quite similar in pathogenesis and presentation to appendicitis, due to the fact that cecal diverticuli, like the appendix, are true diverticuli containing all layers of the intestinal wall. Because a redundant, floppy sigmoid colon can extend to the right side of the abdomen, patients with sigmoid diverticulitis can sometimes present with right lower quadrant pain. Those patients typically describe a quicker progression to localized tenderness, as well as a prodrome of an alteration in bowel habits. Malignancies can present with acute right lower quadrant pain due to perforation of a cecal carcinoma or appendicitis caused by a mass obstructing the appendiceal orifice.39 These patients will also typically have guaiac-positive stools, anemia, and a history of weight loss.

In women of childbearing years, the diagnosis of right lower quadrant pain can be even more difficult. In addition to the causes of right lower quadrant pain mentioned for young men, young women can also have pain from obstetric and gynecological causes such as ruptured ovarian cyst or follicle, ovarian torsion, ectopic pregnancy, acute salpingitis, and tubo-ovarian abscess. A complete history including recent menstrual history, as well as pelvic examination, can be helpful in differentiating these causes of pain from acute appendicitis. Nonetheless, appendicitis can be difficult to diagnose in this patient population, and higher rates of misdiagnosis have been described in women of childbearing age.

These studies show that fecaliths are not pathognomonic for appendicitis, as some patients with abdominal pain and a fecalith have a normal appendix. In addition, fecaliths are not common enough in patients with appendicitis to be used as a reliable sign. As a result, plain abdominal radiographs are neither helpful nor cost effective and are not recommended for the diagnosis of acute appendicitis. Plain radiographs are indicated in elderly patients with severe abdominal pain, in whom a perforated viscus is included in the differential diagnosis. In this patient population, an upright chest x-ray can assess for the presence of free air.

Abdominal ultrasonography is a popular imaging modality for acute appendicitis. Findings that suggest appendicitis include thickening of the appendiceal wall, loss of wall compressibility, increased echogenicity of the surrounding fat signifying inflammation, and loculated pericecal fluid . The advantages of ultrasound include its widespread availability, as well as the avoidance of ionizing radiation and the side effects of intravenous contrast such as renal toxicity and allergic reactions. In addition, ultrasound (both abdominal and transvaginal) is particularly useful in assessing obstetric and gynecological causes of abdominal pain in women of childbearing age. Ultrasound is highly operator-dependent, however, and it is frequently unable to visualize the normal appendix. A recent meta-analysis of 14 prospective studies showed ultrasound to have a sensitivity of 0.86 and a specificity of 0.81.

Computed tomography (CT) is yet another imaging modality for acute appendicitis. CT benefits from a high diagnostic accuracy for appendicitis and visualization and diagnosis of many of the other causes of abdominal pain that can be confused with appendicitis. The radiographic findings of appendicitis on CT include a dilated (>6 mm), thick-walled appendix that does not fill with enteric contrast or air, as well as surrounding fat stranding to suggest inflammation.In a meta-analysis of 12 prospective studies, CT demonstrated a sensitivity of 0.94 and a specificity of 0.95.CT thus has a high negative predictive value, making it particularly useful in excluding appendicitis in patients for whom the diagnosis is in doubt. Appendicitis is highly unlikely if enteric contrast fills the lumen of the appendix and no surrounding inflammation is present. The clinician must remember, however, that a CT performed early in the course of appendicitis might not show the typical radiographic findings. In confusing cases, it is reasonable to repeat the CT after 24 hours of observation.

A number of recent prospective studies have compared the accuracy of CT and ultrasound in imaging the appendix .Balthazar and associates35 performed CT and ultrasound on 100 consecutive patients with suspected appendicitis. The sensitivity of CT was considerably higher (96% for CT, 76% for ultrasound), while the specificity was comparable (89% for CT, 91% for ultrasound), yielding a higher accuracy for CT (94% versus 83%). CT was also able to provide an alternative diagnosis in more patients and was better able to visualize abscesses or phlegmons . Horton and colleagues36 randomized patients with suspected appendicitis to either CT or ultrasound. Their findings echo those of Balthazar, with both CT and ultrasound having high specificity (100% for CT, 90% for US) but CT having significantly higher sensitivity (97% versus 76%). Yet another prospective study showed similar results, with CT having higher sensitivity (96% versus 62%) and specificity (92% versus 71%) than ultrasound.Again, CT was also better able to visualize other intra-abdominal pathology in the absence of appendicitis.

In a study of 100 patients evaluated by CT with rectal and intravenous contrast, Rao and coworkers showed that CT can reduce the use of hospital resources and costs. CT changed the management of 59 patients, avoiding 13 unnecessary appendectomies and eliminating a total of 50 inpatient hospital days for observation of unexplained abdominal pain. Even factoring in the cost of the CT scans, the authors calculated a net savings of $447 (U.S. dollars) per patient.

Taken together, these studies suggest an algorithm for evaluation of patients with suspected acute appendicitis. Patients with a history, physical examination, and laboratory studies classic for appendicitis should undergo urgent appendectomy. In those with an evaluation suggestive but not convincing for appendicitis, further imaging is indicated. In women of childbearing age, this should begin with a pelvic ultrasound to evaluate for ovarian pathology. Following this, the study of choice is an abdominopelvic CT because of its accuracy in diagnosing both appendiceal and other intra-abdominal pathology. This can be supplemented with rectal contrast CT, if needed, to better visualize the appendix.atients with a CT showing appendicitis are taken for appendectomy. In many instances, patients with a normal CT do not require hospital admission. If symptoms persist, admission to the hospital for observation and perhaps a repeat CT scan is warranted.