**4. Diagnosis**

The diagnosis of appendicitis is predominantly a clinical one. The history and examination are pivotal to determining the correct diagnosis. The pain can be a generalised colicky abdominal pain that became more localised to the right iliac fossa over the course of three days. Owing to the embryological origin of the appendix as a midline structure, the majority of patients with acute appendicitis first notice a pain which starts in the region of the umbilicus. This is usually a dull ache or it may be colicky pain when the appendix lumen is obstructed. The pain may change from an intermittent pain to a constant localised sharp pain. After a period of time the pain shifts to the right lower quadrant of the abdomen

Appendicitis and Appendicectomy 141

It is suggestive that there is irritation at the peritoneum where it comes into contact with the appendix. Rovsing's sign can be demonstrated by palpating the left iliac area which results in stretching of the underlying peritoneum. This induces pain in the right iliac fossa due to irritation of the inflamed peritoneum. Digital rectal examination can elicit tenderness on the

Fig. 1. Diagramatic illustration of McBurneys point (1) with regards to the umbilicus (2) and

In females of child bearing age it is important to consider the possibility of pregnancy particularly if the patient was sexually active. An ectopic pregnancy should be considered in the potential differential diagnosis which can often present with pain in the lower quadrants. The pain associated with ectopic pregnancies often radiates to the shoulder. A history of the patient's menstrual cycle and sexual activity and contraception can help in elimination of this differential. It is important to assess beta HCG levels on admission as this would determine further management. Ultasonography and CT scanning are the best noninvasive means of investigating appendicitis. The scan may show an abnormal appendix or an appendicolith with a diameter of over 6mm. The blood results will often have a rise in

the inflammatory markers including white cell count and C-Reactive protein (CRP).

ipsilateral side to the appendix.

the anterior superior iliac spine (3).

Fig. 2. Various positions of the vermiform appendix.

owing to the inflamed appendix irritating the parietal peritoneum. Approximately 30% of patients do not experience this shift of pain and their symptoms commence in the right iliac fossa. Nausea and vomiting are common and anorexia is inevitable. About 20% of patients will also have diarrhoea especially when the appendix lies in the pelvis.

There can be other features in the history suggestive of appendicitis. This includes episodes of vomiting, fever and anorexia. Points to exclude in the history are changes to bowel habits and urinary symptoms. In some cases the inflamed appendix can irritate the bladder due to the close proximity. This however can be supported by a negative urinalysis. The possibility of mesenteric adenitis should be considered in children. This is triggered by viral pathogens and manifests initially as a respiratory tract infection or generalised malaise and fever prior to the onset of abdominal symptoms. Although mesenteric adenitis is more common in children, it still should be considered in young adults as such a diagnosis would not require surgical intervention. It presents very similarly to acute appendicitis however subtle differences do exist. Often the pain of mesenteric adenits can move location when the patient moves whereas in appendicitis it is fixed to the right iliac fossa. Inflammatory bowel disease such as Crohn's often presents with ileocaecal disease and can present similarly to appendicitis. In such cases a mass could be palpated in the right iliac fossa, without any extraintestinal signs. The clinical history alone is not enough to diagnose the condition therefore examination and investigation are essential.

Most patients with appendicitis have a low grade fever and some tachycardia. A very high temperature (above 39 oC) indicates probable abscess formation or other cause of infection. The site of maximum tenderness is usually at McBurney's point. In patients with inflammation of a retro-caecal appendix the pain may be considerably higher and more lateral. Alternatively in pelvic appendicitis, the pain may be lower and almost midline. The abdomen may show signs of guarding in 90% of patients with acute appendicitis. In patients with perforation of the appendix they will have generalised peritonitis and the area of guarding may extend beyond the right iliac fossa. Rebound tenderness is a useful sign. In some patients an appendix mass could be felt on abdominal examination.

On general examination fever is an important sign indicative of an inflammatory condition. A foetor is also detected in 50 % of patients. In children, general observation of discomfort associated with movement or posture is also indicative. Abdominal examination should reveal tenderness over the right iliac fossa with or without rebound tenderness or guarding which indicates signs of peritonism. Specific signs of Appendicitis include McBurneys and Rovsing's signs. The appendix lies in the right iliac fossa and is attached to the posteromedial wall of the caecum where the teniae coli unite. The surface marking for the root of the appendix is relatively constant and is situated approximately one third of the distance from the anterior superior iliac spine to the umbilicus. This is referred to as McBurneys point as shown in the diagram (Figure 1).

 In general, the clinical features of appendicitis can vary depending on the position of the appendix. The commonest position of the appendix is retrocaecal. In this position, psoas muscle irritation (exacerbation of pain on hip extension) can be evident. In the subcaecal and pelvic position, supra pubic pain and urinary frequency may be the predominant symptoms with right sided tenderness on rectal or vaginal examination. In the pre and post ileal position, diarrhoea or vomiting may be the presenting features due to irritation of the ileum. On examination for appendicitis it is important to determine if the pain is worst at McBurneys point. Furthermore the patient may describe pain over this area on coughing. Specific localisation of tenderness over this anatomical landmark is indicative that the inflammation is no longer limited to the lumen of the appendix which poorly localises pain.

owing to the inflamed appendix irritating the parietal peritoneum. Approximately 30% of patients do not experience this shift of pain and their symptoms commence in the right iliac fossa. Nausea and vomiting are common and anorexia is inevitable. About 20% of patients

There can be other features in the history suggestive of appendicitis. This includes episodes of vomiting, fever and anorexia. Points to exclude in the history are changes to bowel habits and urinary symptoms. In some cases the inflamed appendix can irritate the bladder due to the close proximity. This however can be supported by a negative urinalysis. The possibility of mesenteric adenitis should be considered in children. This is triggered by viral pathogens and manifests initially as a respiratory tract infection or generalised malaise and fever prior to the onset of abdominal symptoms. Although mesenteric adenitis is more common in children, it still should be considered in young adults as such a diagnosis would not require surgical intervention. It presents very similarly to acute appendicitis however subtle differences do exist. Often the pain of mesenteric adenits can move location when the patient moves whereas in appendicitis it is fixed to the right iliac fossa. Inflammatory bowel disease such as Crohn's often presents with ileocaecal disease and can present similarly to appendicitis. In such cases a mass could be palpated in the right iliac fossa, without any extraintestinal signs. The clinical history alone is not enough to diagnose the condition

Most patients with appendicitis have a low grade fever and some tachycardia. A very high temperature (above 39 oC) indicates probable abscess formation or other cause of infection. The site of maximum tenderness is usually at McBurney's point. In patients with inflammation of a retro-caecal appendix the pain may be considerably higher and more lateral. Alternatively in pelvic appendicitis, the pain may be lower and almost midline. The abdomen may show signs of guarding in 90% of patients with acute appendicitis. In patients with perforation of the appendix they will have generalised peritonitis and the area of guarding may extend beyond the right iliac fossa. Rebound tenderness is a useful sign. In

On general examination fever is an important sign indicative of an inflammatory condition. A foetor is also detected in 50 % of patients. In children, general observation of discomfort associated with movement or posture is also indicative. Abdominal examination should reveal tenderness over the right iliac fossa with or without rebound tenderness or guarding which indicates signs of peritonism. Specific signs of Appendicitis include McBurneys and Rovsing's signs. The appendix lies in the right iliac fossa and is attached to the posteromedial wall of the caecum where the teniae coli unite. The surface marking for the root of the appendix is relatively constant and is situated approximately one third of the distance from the anterior superior iliac spine to the umbilicus. This is referred to as

 In general, the clinical features of appendicitis can vary depending on the position of the appendix. The commonest position of the appendix is retrocaecal. In this position, psoas muscle irritation (exacerbation of pain on hip extension) can be evident. In the subcaecal and pelvic position, supra pubic pain and urinary frequency may be the predominant symptoms with right sided tenderness on rectal or vaginal examination. In the pre and post ileal position, diarrhoea or vomiting may be the presenting features due to irritation of the ileum. On examination for appendicitis it is important to determine if the pain is worst at McBurneys point. Furthermore the patient may describe pain over this area on coughing. Specific localisation of tenderness over this anatomical landmark is indicative that the inflammation is no longer limited to the lumen of the appendix which poorly localises pain.

some patients an appendix mass could be felt on abdominal examination.

will also have diarrhoea especially when the appendix lies in the pelvis.

therefore examination and investigation are essential.

McBurneys point as shown in the diagram (Figure 1).

It is suggestive that there is irritation at the peritoneum where it comes into contact with the appendix. Rovsing's sign can be demonstrated by palpating the left iliac area which results in stretching of the underlying peritoneum. This induces pain in the right iliac fossa due to irritation of the inflamed peritoneum. Digital rectal examination can elicit tenderness on the ipsilateral side to the appendix.

Fig. 1. Diagramatic illustration of McBurneys point (1) with regards to the umbilicus (2) and the anterior superior iliac spine (3).

Fig. 2. Various positions of the vermiform appendix.

In females of child bearing age it is important to consider the possibility of pregnancy particularly if the patient was sexually active. An ectopic pregnancy should be considered in the potential differential diagnosis which can often present with pain in the lower quadrants. The pain associated with ectopic pregnancies often radiates to the shoulder. A history of the patient's menstrual cycle and sexual activity and contraception can help in elimination of this differential. It is important to assess beta HCG levels on admission as this would determine further management. Ultasonography and CT scanning are the best noninvasive means of investigating appendicitis. The scan may show an abnormal appendix or an appendicolith with a diameter of over 6mm. The blood results will often have a rise in the inflammatory markers including white cell count and C-Reactive protein (CRP).

Appendicitis and Appendicectomy 143

Active observation is advocated for patients with equivocal symptoms, signs and laboratory results. Surgical exploration has been accompanied by an incidental appendicectomy in a considerable number of cases. Authors of large prospective studies report a 15%–32% removal rate of normal appendices at surgery. The reported negative appendicectomy rate for men varies from 7 % to 15 %, whereas that for women of child bearing age lies between 22 % and 47 % . This high rate of unnecessary appendicectomies has considerable morbidity and high cost to the health care system. A large population based study found that patients undergoing negative appendicectomy have prolonged hospitalisation, increased infectious complications and higher rates of case fatality when compared with patients with appendicitis. The national cost of hospitalisation was also higher. This may be due to concomitant disease which necessitated the presentation of right iliac fossa pain which

A number of studies have emphasised the value of laparoscopy as a diagnostic and operative tool particularly in young women. Diagnostic laparoscopy has been found reliable in the assessment of the appendix and has reduced the number of unnecessary appendicectomies. In addition, it has been useful in the diagnosis of alternative pathology

In order to reduce total costs, some studies have suggested a selective approach in the use of diagnostic laparoscopy. There is evidence however that unless diagnostic laparoscopy is

Historically we have seen progression in the management of right iliac fossa pain from purgation to early appendicectomy. Early surgical dictum necessitated appendicectomy for patients with right iliac fossa pain admitted to hospital with convincing signs and symptoms. Appendicectomy was clearly overdone in the past as the delay in diagnosis of appendicitis contributed to an increase in morbidity and mortality. Indeed delayed diagnosis of appendicitis was the most common cause of litigation against emergency surgeons. In regard to laparoscopic appendicectomy, early reports suggested a high rate of complications particularly intra-abdominal abcess formation which was associated with laparoscopic appendicectomy. A more recent Cochrane review however, has found an equal rate of complications in open and laparoscopic appendicectomy. However, patients operated on by laparoscopy, realised the benefits of laparoscopy in terms of less pain, early

Natural orifice translumenal endoscopic surgery (NOTES) has become an exciting area of surgical development. Significant limitations to this surgical concept include lack of surgical expertise and appropriate flexible instrumentation although both aspects are being addressed. An alternative and competing technology to NOTES is single-incision laparoscopic surgery (SILS). A number of reports have produced encouraging results for single incision appendicectomy but this technique remains in its infancy. A number of skeptics have expressed reservations about the applicability of these two techniques for appendicectomy and it will be a matter for the surgical community uptake and adoption of

In terms of the cost of the utility of laparoscopic appendicectomy, the overall costs might be justified since the use of laparoscopy can increase diagnostic power, provide less postoperative pain and fewer wound infections, decrease hospital stay and return to normal

used routinely, the number of negative appendicectomies remains high.

otherwise remains undiagnosed after appendicectomy.

discharge from hospital and return to normal activities.

these two techniques over the next few years.

when it exists.

**5. Management** 

It is important to ensure that the patient has received adequate analgesia and has had blood tests to ensure clotting is normal before surgery. The patient would also require a 'group and save' due to a small risk of bleeding during or after surgery. Antibiotics are often prescribed as prophylaxis to help reduce the risk of wound infections. The patient may require an NG tube if vomiting to prevent the risk of aspiration.

In order to make the diagnosis of appendicitis and at the same time avoid unnecessary appendicectomies a variety of diagnostic modalities were advanced. A review of the literature suggested that the clinical diagnosis of acute appendicitis based on symptoms, physical findings, and serological tests is relatively inaccurate. Despite having high sensitivity (up to 100%), clinical evaluation has relatively low specificity (73%). This means that surgeons are likely to overestimate the presence of appendicitis in patients who present acutely. Several reports have found the use and diagnostic accuracy (specificity and sensitivity) of ultrasound and computed tomography (CT) to be limited in the preoperative evaluation of patients with suspected appendicitis especially in the emergency setting.

The most common US technique used to examine patients with acute abdominal pain is the graded-compression procedure. With this technique, interposing fat and bowel can be displaced or compressed by means of gradual compression to show underlying structures. Furthermore, if the bowel cannot be compressed, the noncompressibility itself is an indication of inflammation. Curved (3.5–5.0-MHz) and linear (5.0–12.0-MHz) transducers are used most commonly, with frequencies depending on the application and the patient's stature. The reported sensitivity of ultrasonic detection of appendicitis lies between 55 and 98% and the specificity between 78 and 100%.

Computed Tomography (CT) has a higher sensitivity and specificity for the diagnosis of appendicitis. The CT technique used to examine patients with acute abdominal pain generally involves scanning of the entire abdomen after intravenous administration of an iodinated contrast medium. Although abdominal CT can be performed without contrast medium, the intravenous administration of contrast material facilitates good accuracy with a positive predictive value of 95% reported for the diagnosis of appendicitis and a high level of diagnostic confidence, especially in rendering diagnoses in thin patients, in whom fat interfaces may be almost absent. Although rectal or oral contrast material may be helpful in differentiating fluid-filled bowel loops from abscesses in some cases, the use of oral contrast material can markedly increase the time to complete the test in the emergency setting and may be contraindicated for patients who potentially may require anesthesia and surgery. The lack of enteral contrast medium does not seem to hamper the accurate reading of CT images obtained in patients with acute abdominal pain as it does in postoperative patients. Exposure to ionizing radiation is a disadvantage of CT. This risk however should be weighed against the direct diagnostic benefit. CT has been shown to reduce the negativefinding appendectomy rate from 24% to 3%. However, only routine CT in comparison to selective use of CT would achieve such results. CT seems to be more sensitive (96% vs. 76%) and accurate (94% vs. 91%) than US in diagnosing acute appendicitis, whereas they are almost equal when it comes to specificity (89% vs. 91%). CT imaging tailored to evaluate acute appendicitis has proven to be particularly successful with a sensitivity of 100%, specificity of 95%, positive predictive value of 97%, negative predictive value of 100%, and accuracy of 98%.

Based on the clinical diagnosis, surgical exploration for suspected appendicitis is advocated early to prevent progression or perforation with its associated morbidity and mortality.

It is important to ensure that the patient has received adequate analgesia and has had blood tests to ensure clotting is normal before surgery. The patient would also require a 'group and save' due to a small risk of bleeding during or after surgery. Antibiotics are often prescribed as prophylaxis to help reduce the risk of wound infections. The patient may

In order to make the diagnosis of appendicitis and at the same time avoid unnecessary appendicectomies a variety of diagnostic modalities were advanced. A review of the literature suggested that the clinical diagnosis of acute appendicitis based on symptoms, physical findings, and serological tests is relatively inaccurate. Despite having high sensitivity (up to 100%), clinical evaluation has relatively low specificity (73%). This means that surgeons are likely to overestimate the presence of appendicitis in patients who present acutely. Several reports have found the use and diagnostic accuracy (specificity and sensitivity) of ultrasound and computed tomography (CT) to be limited in the preoperative evaluation of patients with suspected appendicitis especially in the emergency setting. The most common US technique used to examine patients with acute abdominal pain is the graded-compression procedure. With this technique, interposing fat and bowel can be displaced or compressed by means of gradual compression to show underlying structures. Furthermore, if the bowel cannot be compressed, the noncompressibility itself is an indication of inflammation. Curved (3.5–5.0-MHz) and linear (5.0–12.0-MHz) transducers are used most commonly, with frequencies depending on the application and the patient's stature. The reported sensitivity of ultrasonic detection of appendicitis lies between 55 and

Computed Tomography (CT) has a higher sensitivity and specificity for the diagnosis of appendicitis. The CT technique used to examine patients with acute abdominal pain generally involves scanning of the entire abdomen after intravenous administration of an iodinated contrast medium. Although abdominal CT can be performed without contrast medium, the intravenous administration of contrast material facilitates good accuracy with a positive predictive value of 95% reported for the diagnosis of appendicitis and a high level of diagnostic confidence, especially in rendering diagnoses in thin patients, in whom fat interfaces may be almost absent. Although rectal or oral contrast material may be helpful in differentiating fluid-filled bowel loops from abscesses in some cases, the use of oral contrast material can markedly increase the time to complete the test in the emergency setting and may be contraindicated for patients who potentially may require anesthesia and surgery. The lack of enteral contrast medium does not seem to hamper the accurate reading of CT images obtained in patients with acute abdominal pain as it does in postoperative patients. Exposure to ionizing radiation is a disadvantage of CT. This risk however should be weighed against the direct diagnostic benefit. CT has been shown to reduce the negativefinding appendectomy rate from 24% to 3%. However, only routine CT in comparison to selective use of CT would achieve such results. CT seems to be more sensitive (96% vs. 76%) and accurate (94% vs. 91%) than US in diagnosing acute appendicitis, whereas they are almost equal when it comes to specificity (89% vs. 91%). CT imaging tailored to evaluate acute appendicitis has proven to be particularly successful with a sensitivity of 100%, specificity of 95%, positive predictive value of 97%, negative predictive value of 100%, and

Based on the clinical diagnosis, surgical exploration for suspected appendicitis is advocated early to prevent progression or perforation with its associated morbidity and mortality.

require an NG tube if vomiting to prevent the risk of aspiration.

98% and the specificity between 78 and 100%.

accuracy of 98%.

Active observation is advocated for patients with equivocal symptoms, signs and laboratory results. Surgical exploration has been accompanied by an incidental appendicectomy in a considerable number of cases. Authors of large prospective studies report a 15%–32% removal rate of normal appendices at surgery. The reported negative appendicectomy rate for men varies from 7 % to 15 %, whereas that for women of child bearing age lies between 22 % and 47 % . This high rate of unnecessary appendicectomies has considerable morbidity and high cost to the health care system. A large population based study found that patients undergoing negative appendicectomy have prolonged hospitalisation, increased infectious complications and higher rates of case fatality when compared with patients with appendicitis. The national cost of hospitalisation was also higher. This may be due to concomitant disease which necessitated the presentation of right iliac fossa pain which otherwise remains undiagnosed after appendicectomy.

A number of studies have emphasised the value of laparoscopy as a diagnostic and operative tool particularly in young women. Diagnostic laparoscopy has been found reliable in the assessment of the appendix and has reduced the number of unnecessary appendicectomies. In addition, it has been useful in the diagnosis of alternative pathology when it exists.

In order to reduce total costs, some studies have suggested a selective approach in the use of diagnostic laparoscopy. There is evidence however that unless diagnostic laparoscopy is used routinely, the number of negative appendicectomies remains high.
