Appendicitis
A sudden inflammation of the appendix, often caused by a blockage, resulting in severe right lower belly pain and requiring surgical removal.
Emergency Management: Generalized peritonitis from a ruptured appendix causes septic shock. It requires aggressive fluid resuscitation and emergent exploratory laparotomy with abdominal washout.
Acute appendicitis is the inflammation of the vermiform appendix, a blind-ended diverticulum attached to the cecum. It is the most common cause of the "acute abdomen" requiring emergent surgical intervention.
Detailed Overview
The condition begins with obstruction of the appendiceal lumen. This obstruction leads to fluid stasis, bacterial overgrowth, and inflammation. As pressure builds within the appendix, it compresses venous and lymphatic drainage, causing wall ischemia and necrosis. If surgical removal (appendectomy) is not performed promptly, the ischemic wall will perforate, spilling infected fecal matter into the peritoneal cavity. This transforms a localized infection into generalized peritonitis, significantly increasing morbidity and mortality. Presentation classically involves migratory pain, moving from the umbilicus to the right lower quadrant.
Epidemiology & Demographics
Lifetime risk is approximately 7-8%. It is most common in the second and third decades of life (ages 10-30), with a slight male predominance (1.4:1).
Etiological Mechanism
The primary etiology is luminal obstruction. In adults, this is most commonly caused by a fecalith (a hard piece of stool). In children and adolescents, lymphoid hyperplasia (often following a viral infection) is the most frequent cause. Rare causes include foreign bodies, tumors (carcinoid), or parasites (Ascaris lumbricoides).
Primary Causes
Fecalith (Hardened stool)
Lymphoid Hyperplasia
Foreign Bodies
Neoplasm
1. The narrow appendiceal lumen becomes obstructed. 2. The appendiceal mucosa continues to secrete mucus, causing rapid distension and an increase in intraluminal pressure. 3. Visceral afferent nerve fibers are stretched, causing diffuse, poorly localized periumbilical pain. 4. Resident gut flora (E. coli, Bacteroides fragilis) rapidly multiply within the stagnant fluid. 5. Increased pressure exceeds venous pressure, causing venous congestion, edema, and ischemia. 6. The inflammatory process extends to the serosa and the adjacent parietal peritoneum. This shifts the pain to a sharp, localized somatic pain in the right lower quadrant. 7. Arterial thrombosis occurs, leading to gangrene and eventual perforation.
Diagnostic Criteria & Guidelines
Clinical diagnosis often aided by scoring systems like the Alvarado Score (MANTRELS). Imaging confirms the diagnosis, especially when clinical presentation is atypical.
1. Keep patient NPO (nothing by mouth). 2. IV fluid resuscitation (Lactated Ringer's). 3. Pre-operative prophylactic IV antibiotics covering gram-negatives and anaerobes (e.g., Cefoxitin 2g IV or Ceftriaxone 1g IV + Metronidazole 500mg IV). 4. Laparoscopic Appendectomy (removal of the appendix).
Second-Line & Adjunctive Therapy
For patients with an established Appendiceal Abscess (delayed presentation >3 days): Non-operative management initially with IV antibiotics and CT-guided percutaneous drainage of the abscess. Interval appendectomy may be performed 6-8 weeks later.
Surgical & Procedural Management
Laparoscopic appendectomy is the gold standard, offering less pain, faster recovery, and lower wound infection rates compared to open appendectomy.
Patient Counseling & Advice
Explain the importance of early surgical intervention to prevent rupture. Inform them that the appendix has no essential function in adults, and living without it has no negative consequences.
Follow-Up & Monitoring Schedule
Outpatient surgical follow-up in 2-3 weeks to check the port-site incisions and review pathology results (to rule out unexpected neuroendocrine tumors).
Preventive Strategies
No proven primary prevention strategies.
Excellent. Mortality for non-perforated appendicitis is < 0.1%. Mortality rises to up to 5% in the elderly with perforated appendicitis.