Introduction

Acute appendicitis is acute inflammation and infection of the vermiform appendix, which is most commonly referred to simply as the appendix. The appendix is a blind-ending structure arising from the cecum. Acute appendicitis is one of the most common causes of abdominal pain and is the most frequent condition leading to emergent abdominal surgery in children. The appendix may be involved in other infectious, inflammatory, or chronic processes that can lead to appendectomy; however, this article focuses on acute appendicitis.

Anatomy

The vermiform appendix is generally 5-10 cm in length. It arises from the cecum, which in most children is located in the right lower quadrant of the abdomen.

Although the base of the appendix is fixed to the cecum, the tip can be located in the pelvis, retrocecum, or extraperitoneum. Note that the anatomic position of the appendix determines the symptoms and the site of tenderness when the appendix becomes inflamed.

Pathophysiology

Once the appendix becomes obstructed, bacteria trapped within the appendiceal lumen begin to multiply, and the appendix becomes distended. The increased intraluminal pressure obstructs venous drainage, and the appendix becomes congested and ischemic.

The combination of bacterial infection and ischemia produce inflammation, which progresses to necrosis and gangrene. When the appendix becomes gangrenous, it may perforate. The progression from obstruction to perforation usually takes place over 72 hours.

During the initial stage of appendicitis, the patient feels only periumbilical pain due to the T10 innervation of the appendix. As the inflammation worsens, an exudate forms on the appendiceal serosal surface. When the exudate touches the parietal peritoneum, a more intense and localized pain develops.

If the contents become walled off and form an abscess, the pain and tenderness may be localized to the abscess site. If the contents are not walled off and the fluid is able to travel throughout the peritoneum, the pain and tenderness become generalized.

Causes

Dental caries is an infectious and transmissible disease intiated by a heterogeneous group of gram-positive bacteria present in the biofilm that forms on teeth soon after eruption. This complex community of bacteria, termed dental plaque, contains Streptococcus mutans, which is a necessary agent for the production of dental caries. S. mutans has been shown to be transmissible from parents or caregivers to infants at the time of tooth eruption. The dental health of direct caregivers thus becomes an important factor in the prevention of dental caries.

Caries can occur in teeth of persons of any age, but when the disease occurs in children younger than 3 years, the condition is termed early childhood caries. Previously, most descriptions of early childhood caries focused on the period of nursing, giving rise to the term nursing bottle caries. It is now recognized that early childhood caries can be present in the absence of bottle- or breast-feeding and conversely does not always result from inappropriate bottle- or breast-feeding practices, indicating that other host susceptibility factors are involved.

Complications

Regardless of age or circumstance, all carious lesions must be eradicated by some means. Failure to do so eventually leads to invasion of the pulp chamber of the tooth with inflammation, pain, swelling, and exudation. Since the tooth pulp is encased within a rigid structure, necrosis of the tissue within the pulp chamber occurs because of the increased pressure, which prevents blood flow. An ensuing buildup of toxic products in this space will force extension of the process into the tissue surrounding the root apices, forming an abscess within the bone. Cellulitis with acute pain Continue reading »