Introduction and Epidemiology

Background

Acute appendicitis is a common and considered as emergency illness and thus immediate treatment needed. it has high morbidity and any delay of the diagnosis can be fatal. It is mildly hard to diagnose acute appendicitis since there is no single sign, clinical features, or diagnostic test that accurately can be used to confirm the diagnosis of acute appendicitis.

Epidemiology

United States:  7% of US population with strong association of family history with mortality rate of 0.2-0.8%

International:  mostly acute appendicitis is high in poor country in which their citizens consume less fibre diet. this because it is believed that high fibre-diet can reduce the feces viscosity, and decrease the incidence of bowel obstruction.

Causes

        1) Obstruction of appendiceal lumen

a)    Fecalith (stool that enters the appendix hardens, 
becomes rock-like, and blocks the lumen)

b)   Gallstone

c)    Tumor

d)   Ball of worms (oxyuriasis vermicularis)

      2) Trauma

a)    Rupture of the appendix –>spread of bacteria outside

the appendix-> periappendiceal abscess

Risk Factors

1.    Low dietary fiber

a)    Dietary fiber can decrease the viscosity of fecesàdecrease bowel transit timeàdiscourage formation of fecaliths

2.    Gender

a)    The risk is approximately 1.4 times greater in male than in female

3.    Age

a)    Occur in all age groups but incidence of appendicitis gradually rises from birth, peaks in the late teen years, and gradually declines in the geriatric years.

4.    Infection

a)    Gastrointestinal infections such as amebiasis, bacterial gastroenteritis, mumps, coxsackievirus B and adenovirus

Signs and Symptoms

APPENDICITIS or ABDOMINAL CRAMP

Which and which you are having??

How you know that you are having appendicitis and not just simply an abdominal cramp?

Below are a list of signs and symptoms that appear when you are succumb to appendicitis...

• Increasing sharp and severe pain at the right iliac fossa (lower abdomen)
• Diffuse, radiating pain
• Pain worsening when walking or coughing

• Nausea and vomiting associated with loss of appetitie

• Low grade fever with chills and rigor

• Constipation

If you or someone around you are presented with such signs and symptoms, DO NOT HESITATE...

DO CALL this emergency number (9-9-9) for HELP ...

Confirmatory Signs

What signs of appendicitis that can lead the doctor to a diagnosis of appendicitis?

• Rovsing's sign :  Palpation of left lower quadrant causes pain in right lower quadrant

• Psoas sign (aka Obraztsova's sign) : Pain on extension of right thigh, relieved by flexing the hip

• Obturator's sign : Pain in hypogastrium on internal rotation of right thigh

• Duphy's sign : Increase pain in right lower quadrant on coughing
• Kosher's sign : Pain in epigastrium on shifting to right iliac region
• Rosenstein's sign : Increase pain in right iliac region when lying on the side
• Bartomier-Michelson's sign : Increase pain in right iliac region when lying on side then lying on supine position during palpation
• Aure-Rozanova's sign : Increase pain in right petite triangle ( lumbar triangle) during palpation with finger
• Blumberg sign : aka rebound tenderness - pain upon removal of pressure from the abdomen

Pathogenesis

Appendicitis is inflammation of appendix which located in right lower abdomen.It is supplied by appendicular artery which is a branch of ileocolic artery.Mostly appendicitis is due to compromised blood supply due to obstruction of its lumen and this will increase ability of bacteria to invade the appendix which found in the gut normally.

Obstruction of the appendix lumen by faecolith, enlarged lymph node, worms, tumour, or indeed foreign objects, will increase intra-luminal pressure, which causes the wall of the appendix to become distended.
Normal mucus secretions continue within the lumen of the appendix, thus causing further build up of intra-luminal pressures in the appendix. This in turn leads to the occlusion of the lymphatic channels, then the venous return, and finally the arterial supply becomes affected.

Reduced blood supply to the wall of the appendix due to increase in intra-luminal pressure will cause the appendix gets little or no nutrition and oxygen. It also cause the appendix has  little or no supply of white blood cells and other natural fighters of infection that normally  found in the blood .This will cause the bacteria which normally found in gut available to the appendix.

Once the bacteria reach the appendix,it will multiply and this will lead inflammation process.This will worsen the obstruction of appendix lumen. This leads to necrosis and perforation of the appendix. Pus formation occurs when nearby white blood cells are recruited to fight the bacterial invasion. The pus that form is a combination of dead white blood cells, bacteria, and dead tissue .

When the content of the appendix like faecolith, pus and mucus secretions are  released into the general abdominal cavity due to perforation or rupture of affected appendix, this will cause  peritonitis

Morphology

 Early stage of acute appendicitis  

Scant neutrophilic exudate throughout the mucosa, submucosa and muscularis propria. Subserosal vessels will become congested and often with perivascular neutrophilic infiltrate. The inflammation transforms the normal glisterning serosa into a dull, granular and red.

Late acute appendicitis 

Dense neutrophils infiltration and fibropurulent serosal exudates over the serosa.Abscess formation with ulceration and suppurative necrosis occur within the wall. Subsequently, acute gangrenous necrosis will occur if there is green-black gangrenous necrosis through the wall extending to the serosa and immediately followed by appendix rupture.

Picture (a) and (b) shows acute appendicitis with neutrophils infiltration throughout mucosa, submucosa and muscalaris layers at different magnification.

Picture above shows the enlargement of appendix and  red inflamed mucosa with an irregular luminal surface.

Diagnosis

Diagnosis is based on patient history and physical examination backed by some laboratory investigation. 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, where tenderness develops. Atypical histories lack this typical progression and may include pain in the right lower quadrant as an initial symptom.

Laboratory Studies

Laboratory tests are not specific for appendicitis but may be helpful to confirm diagnosis in patients with an atypical presentation.

Complete Blood Cells  count. The number of white cells in the blood is a usually less than 10,000cells per cubic millimetre. 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 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. A mild elevation of WBCs is a common finding in patients with acute appendicitis. In these patients, leukocytosis occurs.

Cryo-Reactive Proteins. It is an acute phase response protein produced by the liver in response to any infection or inflammatory process in the body. It is another crude marker of infection or inflammation. CRP lacks specificity and cannot be used to distinguish between sites of infection. A significant rise in CRP with corresponding signs and symptoms of appendicitis is a useful indicator in the diagnosis of appendicitis. CRP levels of greater than 1 mg/dL are commonly reported in patients with appendicitis. Very high levels of CRP in patients with appendicitis indicate gangrenous evolution of the disease, especially if it is associated with leukocytosis and neutrophilia.

Urinalysis. Urinalysis may be useful in differentiating appendicitis from urinary tract conditions. Mild pyuria may occur in patients with appendicitis because of the relationship of the appendix with the right ureter. Severe pyuria is a more common finding in UTI. A urine test or urinalysis is compulsory in women, to rule out ectopic pregnancy in appendicitis.

Imaging Studies

Ultrasound. A healthy appendix usually cannot be viewed with ultrasonography. When appendicitis occurs, the ultrasonogram typically demonstrates a noncompressible tubular structure of 7-9 mm in diameter and shows free fluid collection in right iliac fossa along with a visible appendix without blood flow. Sonographic imaging 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.

Ultrasound image of an acute appendicitis.

Computed tomography (CT scan). CT scan with oral contrast medium or rectal Gastrografin enema may help in diagnosis of appendicitis. It may help differentiate between appendicitis and other pelvic pathologies. The typical findings are a nonfilling appendix with distention and thickened walls of the appendix and the cecum, enlarged mesenteric nodes, and periappendiceal inflammation or fluid.

A CT scan demonstrating acute appendicitis.

Alvarado score. A most widely used scoring systems that have been devised to assist diagnosis.

Symptoms
Migratory right iliac fossa pain	1 point
Anorexia	1 point
Nausea and vomiting	1 point
Signs
Right iliac fossa tenderness	2 points
Rebound tenderness	1 point
Fever	1 point
Laboratory
Leucocytosis	2 points
Shift to left (segmented neutrophils)	1 point
Total score	10 points

A score below 5 is strongly against a diagnosis of appendicitis while a score of 7 or more is strongly predictive of acute appendicitis.

Prognosis

• Appendicectomy is relatively safe with a mortality rate for non-perforated appendicitis of 0.8 per 1,000 and mortality after perforation of 5.1 per 1,000.
• The mortality rate is more than 20% in patients older than 70 years, mainly because of delays in diagnosis and treatment.

Complications

There are several complications of acute appendicitis, including:

1. perforation: as the amount of pus in the appendix increases and the appendix caannot withstand the pressure , it will perforate which means the hole is formed in the inflamed appendix
2. wound infection
3. appendix mass: omentum and small bowel adhere to the appendix and it is represented with fever and a palpable mass
4. appendix abscess
5. suppurative peritonitis: if the infected appendix ruptured, it will releases the infection organisms into peritoneum and lad to peritonitis. If severe, it can cause hemorrhage and lead to hypovolemic shock.

Other than acute complications above,pelvic abscess, pylephlebitis with thrombosis of portal venous drainage, paralytic ileus, subphrenic abscess and septicemia also the complications of acute appendicitis.

There are also long-term complications including intestinal obstruction that caused by adhesions.in the pregnancy cases, maternal mortality is very low in acute appendicitis but increases to 4% with perforation in late pregnancy.fetal mortality is less than 1.5% but increases to 20-35% of the perforation case.

Management

Medical Therapy

Antibiotics have an important role in the treatment of patients with this condition. Antibiotics considered for patients with appendicitis must offer full aerobic and anaerobic coverage. Duration of the administration is closely related to the stage of appendicitis at the time of the diagnosis, considering either intraoperative findings or postoperative evolution. When the patient becomes afebrile and the WBC count normalizes, antibiotic treatment may be stopped. Cefotetan and cefoxitin seem to be the best choices of antibiotics.

Pain from appendicitis can be severe. Strong pain medications (i.e., narcotic pain medications) are recommended for pain management prior to surgery. Morphine is generally the standard of care in adults and children in the treatment of pain from appendicitis prior to surgery.

Surgical Therapy

Appendectomy remains the only curative treatment of appendicitis. The surgical procedure for the removal of the appendix is called an appendicectomy (also known as an appendectomy). Often now the operation can be performed via a laparoscopic approach, or via three small incisions with a camera to visualize the area of interest in the abdomen. If the findings reveal suppurative appendicitis with complications such as rupture, abscess, adhesions, etc., conversion to open laparotomy may be necessary. An open laparotomy incision if required most often centers on the area of maximum tenderness, McBurney's point, in the right lower quadrant. A transverse or a gridiron diagonal incision is used most commonly.

Laparoscopy has some advantages, including decreased postoperative pain, better aesthetic result, a shorter time to return to usual activities, and lower incidence of wound infections or dehiscence. This procedure is cost effective but may require more operative time compared with open appendectomy.

Follow-up

After hospital discharge, patients must have a light diet and limit their physical activity for a period of 2-6 weeks based on the surgical approach (ie, laparoscopic, open appendectomy). The patient should be evaluated by the surgeon in the clinic to determine improvement and to detect any possible complications.