**4. Investigations**

Despite advances in other diagnostic modalities, appendicitis remains a diagnosis based primarily on history and physical examination.

#### **4.1 Alvarado score**

Alvarado scoring system is purely based on history, clinical examination and few laboratory tests and is very easy to apply (**Table 1**) [1].


*Score between 5 and 6: Compatible. Score between 6 and 9: Probable. Score more than 9: Confirmed.*

#### **Table 1.**

*Alvarado scoring for appendicitis.*

### **4.2 Leucocytosis**

It is clear that 80–85 percent of patients with acute appendicitis will have a total white blood cell count of over 10000/m3 . Neutrophilia of >75 percent will occur in 78 percent of patients. However, the white cell count is raised in 25–70 percent of patients with other causes of acute right iliac fossa pain.

A raised white cell count is highly sensitive for acute appendicitis, it is rendered almost useless by a low specificity and it has little diagnostic value.

#### **4.3 Serum fibrinogen**

Fibrinogen is an acute-phase reactant, meaning that elevated fibrinogen levels can be seen the following conditions:


As the acute appendicitis is an acute inflammatory condition serum fibrinogen is useful as novel indicator of ongoing inflammatory process.

#### **4.4 Plain radiograph**

However, there is no single sign that is pathognomic of acute appendicitis in a plain film. Brooks et al. described (1965) several signs in a case of acute appendicitis.


e.Haziness in right lower part.


Plain radiograph has less specificity. It has similar findings and normal findings as well as in other conditions.

Furthermore, irradiation hazard s especially to two groups' most frequently requiring elucidation, namely women of reproductive age and children, as well as the cost and overloading of radiology departments make this investigation of low diagnostic yield unattractive.

#### **4.5 Ultrasound**

If the appendix can be seen on ultrasound examination, this is taken to indicate the presence of acute appendicitis and idea about its position [2]. Structure which is blind-ended, immobile, non-compressible and cannot be displaced by ultrasound probe is appendix. The eco density of appendicular lumen is varying and with changed mucosa and thickened wall gives picture of a bull's eye on ultrasound.

There may be presence of fluid or faecolith in the lumen of the appendix confirming the appendicitis. The ultrasound examination will be non-diagnostic in

*Management of Appendicitis DOI: http://dx.doi.org/10.5772/intechopen.100338*

3–11 percent of cases because of pain, guarding, obesity or overlying gas. Among seven studies in literature, the sensitivity ranges from 75 to 89 percent and the specificity from 86 to 100 percent. Poorer results are also reported for retrocaecal appendices, early appendicitis and perforated appendices.

In the hands of expert ultrasound is highly specific, along with that it has further advantages. Diseases such as mesenteric adenitis, terminal ileitis, ureteric stones and some gynecological disorders can be accurately diagnosed by ultrasound which may not require surgery. In pregnancy ultrasound has major diagnostic role. Need of expertise and special equipment are major disadvantages. Other than this it's difficult to use in obese patients and distended abdomen and low sensitivity in some studies are also disadvantages of the ultrasound.

#### **4.6 CT scanning**

Initial studies evaluated sequential (nonhelical) CT scanning in the diagnosis of appendicitis (**Figure 1**) [2].

#### **Figure 1.**

*Showing inflamed appendix arrows (single headed) pointing to abscess (https://www.google.com/url?s a=i&url=https%3A%2F%2Fradiopaedia.org%2Fcases%2Facute-appendicitis-25&psig=AOvVaw2YL kUq9GxMka1g1e4cq3O0&ust=1626969528328000&source=images&cd=vfe&ved=0CAgQjRxqFwoTCJ Cyt\_zD9PECFQAAAAAdAAAAABAD).*

#### **4.7 Diagnostic peritonial aspiration or lavage**

Peritoneum was punctured with fine bore catheter to aspirate fluid which can detect pus or an abnormal number of leucocytes which can be seen in acute appendicitis. Other than appendicitis gynecological infections and mesenteric adenitis may have same results in aspirated fluid examination. Normal findings of aspiration usually rule out all above mentioned conditions.

#### **4.8 Radio isotope scanning**

Two types of imaging modalities are used:


These techniques relay on the localization of the leukocyte and IgG at the site of appendiceal inflammation, with the use of scintigraphy, the inflamed tissue is observed in the right lower quadrant.

The true potential usefulness of these studies occurs in - patient with persistent symptoms and negative ultrasound and CT studies.

### **4.9 Diagnostic laparoscopy**

Laparoscopy has the attraction of being the only investigation that can view the appendix directly. The criteria used for the diagnosis of acute appendicitis are the identification of an inflamed appendix or the presence of sign of inflammation in the right iliac fossa when no other pathology can be found to account.

Huffman summed up the science of acute appendicitis in laparoscopy:


The major disadvantage of laparoscopy is its invasiveness. It requires a general anesthesia (although some perform laparoscopy under local anesthesia) and is in fact an operation that may result in many of the complications of an abdominal procedure.

#### **4.10 Histopathological diagnosis of acute appendicitis**

Histopathology is considered the gold standard for confirmation of the diagnosis of acute appendicitis [3]. The histologic criterion for the diagnosis of acute appendicitis is neutrophilic infiltration of the muscularis propria (**Figures 2**–**10**).

**Figure 2.** *Microscopy of normal appendix, showing the lumen (low power).*

#### **Figure 3.**

*Microscopy of acute appendicitis is marked by mucosal inflammation and necrosis.*

#### **Figure 4.**

*Acute appendicitis: (Low power) Mucosa shows ulceration and undermining by extensive neutrophilic exudates.*

**Figure 5.** *Acute appendicitis: (High power) Neutrophils extend into and through the wall of appendix.*

**Figure 6.** *Gross specimen: Normal appendix.*

**Figure 7.** *Gross specimen: Acute appendicitis.*

**Figure 8.** *Gross specimen: Appendix cut open with fecoliths in the lumen.*

**Figure 9.** *Gross specimen: Acute appendicitis.*

**Figure 10.** *Gross specimen: Acute appendicitis.*
