Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + Download Section PDF Listen ++ For further information, see CMDT Part 15-30: Appendicitis + Key Features Download Section PDF Listen +++ +++ Essentials of Diagnosis ++ Early: periumbilical pain Later: right lower quadrant pain and tenderness Anorexia, nausea and vomiting, obstipation Tenderness or localized rigidity at McBurney point Low-grade fever Leukocytosis +++ General Considerations ++ The most common abdominal surgical emergency, affecting ~10% of the population Occurs most commonly between the ages of 10 and 30 years Caused by obstruction of the appendix by a fecalith, inflammation, foreign body, or neoplasm If untreated, gangrene and perforation develop within 36 hours + Clinical Findings Download Section PDF Listen +++ +++ Symptoms and Signs ++ Vague, often colicky, periumbilical or epigastric pain Within 12 hours, pain shifts to right lower quadrant, with steady ache worsened by walking or coughing Nausea and one or two episodes of vomiting in almost all Constipation Low-grade fever (< 38°C) Localized tenderness with guarding in the right lower quadrant Rebound tenderness Psoas sign (pain on passive extension of the right hip) Obturator sign (pain with passive flexion and internal rotation of the right hip) Atypical presentations include Pain less intense and poorly localized; tenderness minimal in the right flank Pain in the lower abdomen, often on the left; urge to urinate or defecate Abdominal tenderness absent, but tenderness on pelvic or rectal examination +++ Differential Diagnosis ++ Gastroenteritis or colitis Gynecologic Pelvic inflammatory disease Tubo-ovarian abscess Ovarian torsion Ruptured ectopic pregnancy or ovarian cyst Mittelschmerz Endometriosis Urologic Testicular torsion Acute epididymitis Urinary calculus Pyelonephritis Diverticulitis Meckel diverticulitis Carcinoid of the appendix Perforated colon cancer Crohn ileitis Perforated peptic ulcer Cholecystitis Mesenteric adenitis Typhlitis (neutropenic colitis) Mesenteric ischemia + Diagnosis Download Section PDF Listen +++ +++ Laboratory Tests ++ Moderate leukocytosis (10,000–20,000/mcL) with neutrophilia Microscopic hematuria and pyuria in 25% +++ Imaging Studies ++ Imaging may be useful in patients in whom the diagnosis is uncertain Imaging studies (ultrasonography or CT scanning) suggest alternative diagnosis in up to 15% Useful in the exclusion of adnexal disease in younger women Abdominal CT Most accurate test for diagnosis (sensitivity 94% and specificity 95%) Useful in suspected appendiceal perforation to diagnose a periappendiceal abscess + Treatment Download Section PDF Listen +++ +++ Medications ++ Preoperative broad-spectrum antibiotics with gram-negative and anaerobic coverage reduce the incidence of postoperative infections Recommended intravenous regimens include Cefoxitin or cefotetan 1–2 g every 8 hours Ampicillin-sulbactam 3 g every 6 hours Ertapenem 1 g as a single dose +++ Surgery ++ Surgical appendectomy in patients with uncomplicated appendicitis; when possible, a laparoscopic approach is preferred to open laparotomy Emergency appendectomy in patients with perforated appendicitis with generalized peritonitis +++ Therapeutic Procedures ++ Percutaneous CT-guided drainage of periappendiceal abscess, intravenous fluids and antibiotics, and interval appendectomy after 6 weeks in stable patients with perforated appendicitis + Outcome Download Section PDF Listen +++ +++ Complications ++ Perforation in 20% Periappendiceal abscess Suppurative peritonitis Septic thrombophlebitis (pylephlebitis) of the portal venous system +++ Prognosis ++ Up to 80–90% of patients with uncomplicated appendicitis treated with antibiotics alone for 7 days have resolution of symptoms and signs Conservative management with antibiotics alone may be considered in patients who have nonperforated appendicitis with surgical contraindications or with a strong preference to avoid surgery However, appendectomy is recommended in most patients to prevent recurrent appendicitis (20–35% within 1 year) Mortality rate of uncomplicated appendicitis is extremely low Mortality rate of perforated appendicitis is 0.2%, but 15% in the elderly + References Download Section PDF Listen +++ + +Darwazeh G et al. A systematic review of perforated appendicitis and phlegmon: interval appendectomy or wait-and-see? Am Surg. 2016 Jan;82(1):11–5. [PubMed: 26802841] + +Flum DR. Clinical practice. Acute appendicitis—appendectomy or the "antibiotics first" strategy. N Engl J Med. 2015 May 14; 372(20):1937–43. Erratum in: N Engl J Med. 2015 Jun 4; 372(23):2274. [PubMed: 25970051] + +Jaschinski T et al. Laparoscopic versus open surgery for suspected appendicitis. Cochrane Database Syst Rev. 2018 Nov 28;11:CD001546. [PubMed: 30484855] + +Nimmagadda N et al. Complicated appendicitis: immediate operation or trial of nonoperative management? Am J Surg. 2019 Apr;217(4):713–7. [PubMed: 30635209] + +Poprom N et al. The efficacy of antibiotic treatment versus surgical treatment of uncomplicated acute appendicitis: systematic review and network meta-analysis of randomized controlled trial. Am J Surg. 2019 Jul;218(1):192–200. [PubMed: 30340760]