Overview

We may have all come across extreme lower right abdominal pain in children that mostly denotes appendicitis. But do you have the right knowledge about the very common appendicitis? This article helps you to understand more about appendicitis.

Appendicitis is an inflammation in your appendix. Appendix is a small hollow thin tube of tissue which is part of the intestine. It is a surgical emergency as it can lead to life-threatening infection.¹ It is the most common cause of lower right abdominal pain.

Appendicitis is seen particularly in children and is seen mostly during the second decade of life.

Young children are at high risk and could show delayed symptoms. Upon diagnosis of children, 30%-75% could have perforated appendicitis. A timely diagnosis is necessary but can be equally difficult. A ruptured appendix causes the spread of bacteria to the child’s tummy which can result in peritonitis. The entry of bacteria into the bloodstream can lead to sepsis.

Appendicitis must be ruled out in any patient with acute abdominal pain without prior appendectomy. With time the rate of rupture of the appendix increases.

Neonatal appendicitis is a very rare disease with high mortality. Abdominal distension is the main clinical presentation in young children. The younger the patient, the earlier the perforation occurs. 

A timely diagnosis is a necessary factor to prevent perforation/ rupture to reduce the risk of complications.

Location of appendix

• Vermiform appendix ² is located in the lower right side of the abdomen. Vermiform is a Latin word meaning worm-like and ascribes to its long, tubular structure. It arises from the inferior tip of the cecum
• The length of the appendix ranges from 5 to 35 cm. Average length is 9 cm in an adult and in Neonates the appendix averages 4.5 cm in length
• Appendix has no function in humans
• The appendix is funnel-shaped in infants and also assumes a normal adultlike conical shape by 1-2 years of age.

Cause of appendicitis in children

Obstruction of the appendix:

• It can be caused by inflammation of the wall of the appendix
• Fecalith (hard stools)¹
• Appendicoliths (calcified deposits)
• Gallstones, worms or tumours can cause obstruction of the appendiceal orifice and can lead to increased intraluminal pressure 
• The appendix receives blood supply from the appendicular artery. As intraluminal pressure exceeds the perfusion pressure it can cause ischemic injury. This leads to bacterial overgrowth and triggers an inflammatory response

Lymphoid hyperplasia: The appendix contains large masses of lymphoid tissue in the mucosa and submucosa, and can develop lymphoid hyperplasia which can cause obstruction of the appendix. Lymphoid hyperplasia causes obstruction in young patients.

Who gets appendicitis?

• Appendicitis can occur at any age and is more common in males compared to females
• Appendicitis is seen mainly seen between the ages of 10 and 19 years¹
• Estimated lifetime risk is more in females(25%) compared to males (12%)
• The risk of perforation increases with diagnostic delay. In children 5-12 years old, if the diagnosis is made in less than 24 hours from the outbreak of symptoms, the reported perforation rate is 7%, if between 24-48 hours- 38%, and if more than 48 hours - 98%
• The perforation rate is high (70%) in patients < 3 years, even if the time to diagnosis is less than 48 hours 

Signs and symptoms

Pain is the most common presenting symptom in children, followed by vomiting, fever, diarrhoea and anorexia. 

• Acute abdominal pain: Pain is the first symptom to occur. It begins as a vague periumbilical(belly button) or mid-abdominal pain. It can also be central and usually develops after nonspecific symptoms
• Nausea: occurs after the onset of pain
• Dysuria or hematuria: Due to the proximity of the appendix to the urinary tract painful urination or the presence of blood in urine can occur¹
• Anorexia or eating disorder is common
• Irritability or lethargy
• Abdominal distension

The anatomical position of the inflamed appendix can affect its clinical presentation¹

• Back pain will be present in a retrocecal appendix
• Suprapubic pain will be present in a pelvic appendix
• Right upper quadrant or left lower quadrant pain will be present along the appendix

Evaluation

A timely diagnosis of acute appendicitis in young children is a challenge. Appendicitis can also be easily misdiagnosed. For example, it could be diagnosed as pneumonia, urinary tract infections, pelvic inflammatory disease, etc.

 The diagnostic algorithm given below can be used to assess acute appendicitis in young children:⁴

White blood cell count (WBC)

 When acute appendicitis is suspected white blood cell count (WBC) and C-reactive protein (CRP) are commonly used.⁴

• An Increase in peripheral WBC may be the earliest marker of inflammation but its presence or absence is not significant enough to exclude acute appendicitis
• CRP is more specific than the WBC count
• CRP shows higher sensitivity in finding an abscess formation and appendiceal perforation⁴

Urinalysis

Urinalysis is a test of your urine. Urinalysis is usually normal but may be abnormal due to the inflamed appendix sitting on the bladder or ureter.¹

Imaging

In children suspected of appendicitis abdominal radiographs are recommended.

Appendicitis is a clinical diagnosis. Imaging is not usually required and is unnecessary when the diagnosis is clear. It is helpful in doubtful cases such as in the case of people assigned female at birth in the child-bearing age group.¹

Ultrasound (US)

The use of ultrasound has increased in children. The diagnostic US shows a thickened appendix greater than 6 mm in diameter. If the US is non-diagnostic, further imaging by CT or MRI should be done.

Advantages of ultrasonography:¹

• Lack of ionising radiation exposure
• Low cost compared to other imaging modalities

CT scan

Computed tomography (CT) is considered the radiological gold standard to confirm appendicitis with high specificity and sensitivity.¹

Repeated CT carries an increased risk of cancer in children and its use should therefore be limited. 

Advantages of CT examination

• less operator dependence
• easier visualisation of retrocecal appendix
• less interference of bowel gas
• obesity

The following findings may be seen:

• Dilated appendix greater than 6 mm 
• Periappendiceal inflammation 
• Appendicolith
• Appendiceal or abscess
• Free fluid 

MRI

MRI is particularly useful for pregnant women and children when ultrasound is inconclusive.

Intravenous (IV) gadolinium should not be used during pregnancy since it can cross the placenta. Also, patients with renal insufficiency should not receive IV gadolinium.

The following factors limit MRI use:¹

• Higher cost
• More time is required to acquire images
• A skilled radiologist is required to interpret MRI
• Not widely available

 Differential diagnosis

• Appendicitis in children is a diagnostic challenge
• Gastroenteritis is the most common misdiagnosis³
• Other differential diagnoses include pneumonia, sepsis, urinary tract infection, intussusception,¹ blunt abdominal trauma, Meckel diverticulum, (NEC)Necrotizing enterocolitis⁴

Complications

• Perforation
• Shock
• Pelvic abscess¹
• Wound infection
• Bowel obstruction

Treatment

Appendicitis is treated by:

• Appendectomy
• Antibiotics by vein
• The primary and best treatment for appendicitis is surgery. Appendectomy is the surgical removal of the appendix. An early surgical consultation should be obtained if the patient is evaluated for appendicitis. Do not give anything by mouth (NPO). Intravenously administer isotonic crystalloid fluid
• Antibiotic prophylaxis is given to cover for gram-negative and gram-positive aerobic and anaerobic bacteria and anaerobes (Bacteroides fragilis and Escherichia coli)¹
• Treat nonperforated appendicitis with cefoxitin or cefotetan
• Perforated appendicitis is treated by the following medications
• Carbapenem
• Ticarcillin-clavulanate
• Piperacillin-tazobactam
• Ampicillin-sulbactam
• Provide adequate analgesia

Laparoscopic surgery for appendicitis

Laparoscopic surgery has replaced open surgery for appendicitis and is preferred if the surgical expertise and equipment are available.

• In laparoscopic surgery, the surgeon makes small cuts on the abdomen of your child, inserts a video camera and then with small tools the appendix is removed. The recovery is faster in this method

 Advantages of Laparoscopic surgery:¹

• Quick recovery 
• Shorter hospitalisation
• Lower infection rate
• Laparotomy(open): In this method, a larger incision is made on your child's tummy. This is done in complicated cases and requires a longer recovery period

FAQ’s

How do you treat appendicitis in children?

Appendicitis can be treated by appendectomy and antibiotics. Appendectomy is the best treatment for appendicitis in children as it involves surgical removal of the appendix.

What is the confirmatory diagnostic test for appendicitis?

CT Scan is the confirmatory diagnostic test for appendicitis.

Summary

Appendicitis is the inflammation of the vermiform appendix. This is caused by obstruction of the appendix by fecalith, calcified deposits, gallstones or tumours. Lymphoid hyperplasia also causes inflammation of the wall of the appendix. Abdominal pain in the lower right side of the abdomen is the main symptom of appendicitis. Fever, nausea and vomiting can be seen in children. It is often misdiagnosed as gastroenteritis. Timely diagnosis is necessary for appendicitis since the appendix can rupture and can cause sepsis. Appendicitis is a clinical diagnosis. It can also be diagnosed by Ultrasound, MRI or a CT scan. The primary treatment for appendicitis is surgery. The infected appendix is removed by open or laparoscopic surgery.