Appendicitis



Definition of Appendicitis

Appendicitis is a condition characterized by inflammation of the appendix. The appendix is a finger-shaped pouch that projects out from your colon on the lower right side of your abdomen. This small structure has no known essential purpose, but that doesn’t mean it can’t cause problems. Appendicitis is classified as a medical emergency and many cases require removal of the inflamed appendix, either by laparotomy or laparoscopy. Untreated, mortality is high, mainly because of the risk of rupture leading to infection and inflammation of the intestinal lining (peritoneum) and eventual sepsis, clinically known as peritonitis which can lead to circulatory shock.

Appendicitis causes pain that typically begins around your navel and then shifts to your lower right abdomen. Appendicitis pain typically increases over a period of 12 to 18 hours and eventually becomes very severe.

Appendicitis can affect anyone, but it most often occurs in people between the ages of 10 and 30. The standard appendicitis treatment is surgical removal of the appendix.

Cause of Appendicitis

On the basis of experimental evidence, acute appendicitis seems to be the end result of a primary obstruction of the appendix lumen (the inside space of a tubular structure). Once this obstruction occurs, the appendix subsequently becomes filled with mucus and swells, increasing pressures within the lumen and the walls of the appendix, resulting in thrombosis and occlusion of the small vessels, and stasis of lymphatic flow. Rarely, spontaneous recovery can occur at this point. As the former progresses, the appendix becomes ischemic and then necrotic. As bacteria begin to leak out through the dying walls, pus forms within and around the appendix (suppuration). The end result of this cascade is appendiceal rupture (a ‘burst appendix’) causing peritonitis, which may lead to septicemia and eventually death.

The causative agents include foreign bodies, trauma, intestinal worms, lymphadenitis, and, most commonly, calcified fecal deposits known as appendicoliths or fecaliths. The occurrence ofobstructing fecaliths has attracted attention since their presence in patients with appendicitis is significantly higher in developed than in developing countries, and an appendiceal fecalith is commonly associated with complicated appendicitis. Also, fecal stasis and arrest may play a role, as demonstrated by a significantly lower number of bowel movements per week in patients with acute appendicitis compared with healthy controls. The occurrence of a fecalith in the appendix seems to be attributed to a right-sided fecal retention reservoir in the colon and a prolonged transit time. From epidemiological data, it has been stated that diverticular disease and adenomatous polyps were unknown and colon cancer exceedingly rare in communities exempt from appendicitis. Also, acute appendicitis has been shown to occur antecedent to cancer in the colon and rectum. Several studies offer evidence that a low fiber intake is involved in the pathogenesis of appendicitis. This is in accordance with the occurrence of a right-sided fecal reservoir and the fact that dietary fiber reduces transit time.

Signs and Symptoms of Appendicitis

Pain first, vomiting next and fever last has been described as the classic presentation of acute appendicitis. Since the innervation of the appendix enters the spinal cord at the same level as the umbilicus (belly button), the pain begins stomach-high. Later, as the appendix becomes more swollen and irritates the adjoining abdominal wall, it tends to localize over several hours into the right lower quadrant, except in children under three years. This pain can be elicited through various signs and can be severe.

Signs include localized findings in the right iliac fossa. The abdominal wall becomes very sensitive to gentle pressure (palpation). Also, there is severe pain on sudden release of deep pressure in the lower abdomen (rebound tenderness). In case of a retrocecal appendix (appendix localized behind the cecum), however, even deep pressure in the right lower quadrant may fail to elicit tenderness (silent appendix), the reason being that the cecum, distended with gas, protects the inflamed appendix from the pressure. Similarly, if the appendix lies entirely within the pelvis, there is usually complete absence of abdominal rigidity. In such cases, a digital rectal examination elicits tenderness in the rectovesical pouch. Coughing causes point tenderness in this area (McBurney’s point) and this is the least painful way to localize the inflamed appendix. If the abdomen on palpation is also involuntarily guarded (rigid), there should be a strong suspicion of peritonitis, requiring urgent surgical intervention.

Risk Factors for Appendicitis

Risk factors for Acute Appendicitis are factors that do not seem to be a direct cause of the disease, but seem to be associated in some way. Having a risk factor for Acute Appendicitis makes the chances of getting the condition higher but does not always lead to Acute Appendicitis.

  • Age: Appendicitis can occur in all age groups but it is more common between the ages of 11 and 20.
  • Gender: A male preponderance exists, with a male to female ratio (1.4: 1) and the overall lifetime risk is 8.6% for males and 6.7% for females. A male child suffering from cystic fibrosis is at a higher risk for developing appendicitis.
  • Diet: People whose diet is low in fiber and rich in refined carbohydrates have an increased risk of getting appendicitis.
  • Hereditary: A particular position of the appendix, which predisposes it to infection, runs in certain families. Having a family history of appendicitis may increase a child’s risk for the illness.
  • Seasonal variation: Most cases of appendicitis occur in the winter months – between the months of October and May.
  • Infections: Gastrointestinal infections such as Amebiasis, Bacterial Gastroenteritis, Mumps, Coxsackievirus B and Adenovirus can predispose an individual to Appendicitis.

Diagnosis of Appendicitis

Diagnosis is based on patient history (symptoms) and physical examination backed by an elevation of neutrophilic white blood cells. Histories fall into two categories, typical and atypical. Typical appendicitis usually includes abdominal pain beginning in the region of the umbilicus for several hours, associated with anorexia, nausea or vomiting. The pain then “settles” into the right lower quadrant (or the left lower quadrant in patients with situs inversus totalis), where tenderness develops. The combination of pain, anorexia, leukocytosis, and fever is classic. Atypical histories lack this typical progression and may include pain in the right lower quadrant as an initial symptom. Atypical histories often require imaging with ultrasound and/or CT scanning.

Clinical

Aure-Rozanova sign

Increased pain on palpation with finger in right Petit triangle (can be a positive Shchetkin-Bloomberg’s sign) – typical in retrocecal position of the appendix.

Also referred as rebound tenderness. Deep palpation of the viscera over the suspected inflamed appendix followed by sudden release of the pressure causes the severe pain on the site indicating positive Blumberg’s sign and peritonitis.

Bartomier-Michelson’s sign

Increased pain on palpation at the right iliac region as patient lies on his/her left side compared to when patient was on supine position.

Dunphy’s sign

Increased pain in the right lower quadrant with coughing.

Kocher’s (Kosher’s) sign

From the history given, the appearance of pain in the epigastric region or around the stomach at the beginning of disease with a subsequent shift to the right iliac region.

Massouh sign

This sign, developed in and popular in southwest England, describes a firm swish of the examiner’s index and middle finger across the patient’s abdomen from xiphoid sternum to first the left and then the right iliac fossa. A positive Massouh sign is a grimace of the patient upon a right sided (and not left) sweep, because initial stage appendicitis usually causes localised irritation of the well-innervated peritoneum.

Obturator sign

If an inflamed appendix is in contact with the obturator internus, spasm of the muscle (called the obturator sign) can be demonstrated by flexing and internal rotation of the hip. This maneuver will cause pain in the hypogastrium.

Psoas sign

Psoas sign or “Obraztsova’s sign” is right lower-quadrant pain that is produced with either the passive extension of the patient’s right hip (patient lying on left side, with knee in flexion) or by the patient’s active flexion of the right hip while supine. The pain elicited is due to inflammation of the peritoneum overlying the iliopsoas muscles and inflammation of the psoas muscles themselves. Straightening out the leg causes pain because it stretches these muscles, while flexing the hip activates the iliopsoas and therefore also causes pain.

Rovsing’s sign

Continuous deep palpation starting from the left iliac fossa upwards (counterclockwise along the colon) may cause pain in the right iliac fossa, by pushing bowel contents towards the ileocaecal valve and thus increasing pressure around the appendix.[25]

Sitkovskiy (Rosenstein)’s sign

Increased pain in the right iliac region as patient lies on his/her left side.

Blood and urine test

Most people suspected of having appendicitis would be asked to do a blood test. Half of the time, the blood test is normal, so it is not that useful in diagnosing appendicitis.

Two forms of blood tests are commonly done: Full blood count (FBC), also known as complete blood count (CBC), is an inexpensive and commonly requested blood test. It involves measuring the blood for its richness in red blood cells, as well as the number of the various white blood cell constituents in it. The number of white cells in the blood is usually less than 10,000 cells per cubic millimeter. An abnormal rise in the number of white blood cells in the blood is a crude indicator of infection or inflammation going on in the body. Such a rise is not specific to appendicitis alone. If it is abnormally elevated, with a good history and examination findings pointing towards appendicitis, the likelihood of having the disease is higher. In pregnancy, elevation of white blood cells may be normal, without any infection present.

C-reactive protein (CRP) is an acute-phase response protein produced by the liver in response to any infection or inflammatory process in the body. Again, like the FBC, it is not a specific test. It is another crude marker of infection or inflammation. Inflammation at ANY site can lead to a rise in CRP. A significant rise in CRP, with corresponding signs and symptoms of appendicitis, is a useful indicator in the diagnosis of appendicitis. If the CRP continues to be normal after 72 hours of the onset of pain, the appendicitis likely will resolve on its own without intervention. A worsening CRP with good history is a sure signal of impending perforation or rupture and abscess formation.

A urine test in appendicitis is usually normal. It may, however, show blood if the appendix is rubbing on the bladder, causing irritation. It is important to rule out an ectopic pregnancy in women of childbearing age.

Imaging

Appendicitis in children is common enough to merit special attention. Because of the health risks of exposing children to radiation, many medical societies recommend that in confirming a diagnosis with children the ultrasound is a preferred first choice with x-rays being a legitimate follow-up when warranted. CT scan is more accurate than ultrasound for the diagnosis of appendicitis in adults and adolescents. CT scan has a sensitivity of 94%, specificity of 95%. Ultrasonography had an overall sensitivity of 86%, a specificity of 81%.

X–Ray

In 10% of patients with appendicitis, plain abdominal X-ray may demonstrate hard formed feces in the lumen of the appendix (fecolith). It is agreed that the finding of Fecolith in the appendix on X-ray alone is a reason to operate to remove the appendix, because of the potential to cause worsening symptoms. In this respect, a plain abdominal X-ray may be useful in the diagnosis of appendicitis, though plain abdominal X- ray is no longer requested routinely in suspected cases of appendicitis. An abdominal X-ray may be done with a barium enema contrast to diagnose appendicitis. Barium enema is whitish fluid that is passed up into the rectum to act as a contrast. It will usually fill the whole of the large bowel. In normal appendix, the lumen will be present and the barium fills it up and is seen when the X-ray film is shot. In appendicitis, the lumen of the appendix will not be visible on the barium film.

Ultrasound

Ultrasonography and Doppler sonography provide useful means to detect appendicitis, especially in children, and shows free fluid collection in the right iliac fossa, along with a visible appendix without blood flow in color Doppler. In some cases (15% approximately), however, ultrasonography of the iliac fossa does not reveal any abnormalities despite the presence of appendicitis. This is especially true of early appendicitis before the appendix has become significantly distended and in adults where larger amounts of fat and bowel gas make actually seeing the appendix technically difficult. Despite these limitations, sonographic imaging in experienced hands can often distinguish between appendicitis and other diseases with very similar symptoms, such as inflammation of lymph nodes near the appendix or pain originating from other pelvic organs such as the ovaries or fallopian tubes.

Computed tomography

Where it is readily available, CT scan has become frequently used, especially in adults whose diagnosis is not obvious on history and physical examination. Concerns about radiation, however, tend to limit use of CT in pregnant women and children. A properly performed CT scan with modern equipment has a detection rate (sensitivity) of over 95%, and a similar specificity. Signs of appendicitis on CT scan include lack of oral contrast (oral dye) in the appendix, direct visualization of appendiceal enlargement (greater than 6 mm in cross-sectional diameter), and appendiceal wall enhancement with IV contrast (IV dye). The inflammation caused by appendicitis in the surrounding peritoneal fat (so called “fat stranding”) can also be observed on CT, providing a mechanism to detect early appendicitis and a clue that appendicitis may be present even when the appendix is not well seen. Thus, diagnosis of appendicitis by CT is made more difficult in very thin patients and in children, both of whom tend to lack significant fat within the abdomen. The utility of CT scanning is made clear, however, by the impact it has had on negative appendectomy rates. For example, use of CT for diagnosis of appendicitis in Boston, MA has decreased the chance of finding a normal appendix at surgery from 20% in the pre-CT era to only 3% according to data from the Massachusetts General Hospital.

Scoring systems

Alvarado score

A number of clinical and laboratory-based scoring systems have been devised to assist diagnosis. The most widely used is Alvarado score. A score below 5 is strongly against a diagnosis of appendicitis,[30] while a score of 7 or more is strongly predictive of acute appendicitis. In patients with an equivocal score of 5 or 6, a CT scan is used to further reduce the rate of negative appendicectomy.

Tzanakis scoring

Tzanakis scoring: Tzanakis and colleagues, in 2005 published a simplified system, now called the Tzanakis scoring system for appendicitis, to aid the diagnosis of appendicitis. It incorporates the presence of four variables made up of specific signs and symptoms (presence of right lower abdominal tenderness = 4 points and rebound tenderness = 3), laboratory findings (presence of white blood cells greater than 12,000 in the blood = 2), as well as ultrasound findings (presence of positive ultrasound scan findings of appendicitis = 6), to which scores are allocated, in the computing of a scoring to predict the presence of appendicitis.
The maximum score is a total score of 15; where a patient scores 8 or more points, there is greater than 96% chance that appendicitis exists.

Pathology

The definitive diagnosis is based on pathology. The histologic findings of appendicits are neutrophils in the muscularis propria.

Periappendicits, inflammation of tissues around the appendix, is often found in conjunction with other abdominal pathology.[31]

Differential diagnosis

In children: Gastroenteritismesenteric adenitisMeckel’s diverticulitisintussusceptionHenoch-Schönlein purpura, lobar pneumoniaurinary tract infection (abdominal pain in the absence of other symptoms can occur in children with UTI), new-onset Crohn’s disease or ulcerative colitispancreatitis, and abdominal trauma from child abusedistal intestinal obstruction syndrome in children with cystic fibrosis; typhlitis in children with leukemia;

In women: A pregnancy test is important in all women of child bearing age, as ectopic pregnancies and appendicitis present similar symptoms. Other causes menarche, dysmenorrhea, pelvic inflammatory diseaseendometriosisMittelschmerz (the passing of an egg in the ovaries approximately two weeks before an expected menstruation cycle).

In men: testicular torsion;

In adults: new-onset Crohn’s diseaseulcerative colitis, regional enteritis, renal colic, perforated peptic ulcerpancreatitisrectus sheath hematoma;

In elderly: diverticulitis, intestinal obstruction, colonic carcinomamesenteric ischemia, leaking aortic aneurysm.

Prevention from Appendicitis

There is no way to prevent appendicitis. However, appendicitis is less common in people who eat foods high in fiber, such as fresh fruits and vegetables.

Treatment of Appendicitis

Acute appendicitis is typically managed by surgery however in uncomplicated cases antibiotics are both effective and safe. While antibiotics are effective for treating uncomplicated appendicitis 20% of people had a recurrence within a year and required eventual appendectomy.

Pain

Pain medications (such as morphine) do not appear to affect the accuracy of the clinical diagnosis of appendicitis and therefore should be given early in the persons care. Historically there were concerns among some general surgeons that analgesics would affect the clinical exam in children and thus some recommended that they not be given until the surgeon in question was able to examine the person for themselves.

Surgery

The surgical procedure for the removal of the appendix is called an appendicectomy. Laparoscopic removal (via three small incisions with a camera to visualize the area of interest in the abdomen) seem to have some advantages over an open procedures especially in young females and the obese.

Laparotomy

Laparotomy is the traditional type of surgery used for treating appendicitis. This procedure consists in the removal of the infected appendix through a single larger incision in the lower right area of the abdomen. The incision in a laparotomy is usually 2 to 3 inches (51 to 76 mm) long. This type of surgery is used also for visualizing and examining structures inside the abdominal cavity and it is called exploratory laparotomy.
During a traditional appendectomy procedure, the patient is placed under general anesthesia to keep the muscles completely relaxed and to keep the patient unconscious. The incision is two to three inches (76 mm) long and it is made in the right lower abdomen, several inches above the hip bone. Once the incision opens the abdomen cavity and the appendix is identified, the surgeon removes the infected tissue and cuts the appendix from the surrounding tissue. After the surgeon inspects carefully and closely the infected area and there are no signs that surrounding tissues are damaged or infected, he will start closing the incision. This means sewing the muscles and using surgical staples or stitches to close the skin up. In order to prevent infections the incision is covered with a sterile bandage.

The entire procedure does not last longer than an hour if complications do not occur.

Laparoscopic surgery

The newer method to treat appendicitis is the laparoscopic surgery. This surgical procedure consists of making three to four incisions in the abdomen, each 0.25 to 0.5 inches (6.4 to 13 mm) long. This type of appendectomy is made by inserting a special surgical tool called laparoscope into one of the incisions. The laparoscope is connected to a monitor outside the patient’s body and it is designed to help the surgeon to inspect the infected area in the abdomen. The other two incisions are made for the specific removal of the appendix by using surgical instruments. Laparoscopic surgery also requires general anesthesia and it can last up to two hours. The latest methods are NOTES appendectomy pioneered in Coimbatore, India where there is no incision on the external skin and SILS (Single incision laparoscopic Surgery) where a single 2.5 cm incision is made to perform the surgery. This finding was very significant to the appendicitis patients and now thousands of people every year survive.

Pre surgery

The treatment begins by keeping the patient away from eating or drinking in preparation for surgery. An intravenous drip is used to hydrate the patient. Antibiotics given intravenously such as cefuroxime and metronidazole may be administered early to help kill bacteria and thus reduce the spread of infection in the abdomen and postoperative complications in the abdomen or wound. Equivocal cases may become more difficult to assess with antibiotic treatment and benefit from serial examinations. If the stomach is empty (no food in the past six hours) general anaesthesia is usually used. Otherwise, spinal anaesthesia may be used.

Once the decision to perform an appendectomy has been made, the preparation procedure takes approximately one to two hours. Meanwhile, the surgeon will explain the surgery procedure and will present the risks that must be considered when performing an appendectomy. With all surgeries there are certain risks that must be evaluated before performing the procedures. However, the risks are different depending on the state of the appendix. If the appendix has not ruptured, the complication rate is only about 3% but if the appendix has ruptured, the complication rate rises to almost 59%. The most usual complications that can occur are pneumonia, hernia of the incision, thrombophlebitis, bleeding or adhesions. Recent evidence indicates that a delay in obtaining surgery after admission results in no measurable difference in patient outcomes.

The surgeon will also explain how long the recovery process should take. Abdomen hair is usually removed in order to avoid complications that may appear regarding the incision. In most of the cases patients experience nausea or vomiting which requires specific medication before surgery. Antibiotics along with pain medication may also be administrated prior to appendectomies.

After surgery

Hospital lengths of stay typically range from a few hours to a few days, but can be a few weeks if complications occur. The recovery process may vary depending on the severity of the condition, if the appendix had ruptured or not before surgery. Appendix surgery recovery is generally a lot faster if the appendix did not rupture. It is important that patients respect their doctor’s advice and limit their physical activity so the tissues can heal faster. Recovery after an appendectomy may not require diet changes or a lifestyle change.
After surgery occurs, the patient will be transferred to an postanesthesia care unit so his or her vital signs can be closely monitored to detect anesthesia- and/or surgery-related complications. Pain medication may also be administered if necessary. After patients are completely awake, they are moved into a hospital room to recover. Most individuals will be offered clear liquids the day after the surgery, then progress to a regular diet when the intestines start to function properly. Patients are recommended to sit up on the edge of the bed and walk short distances for several times a day. Moving is mandatory and pain medication may be given if necessary. Full recovery from appendectomies takes about four to six weeks, but can be prolonged to up to eight weeks if the appendix had ruptured.