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Acute appendicitis in adults: Clinical manifestations and differential diagnosis

Ronald F Martin, MD
Section Editor
Martin Weiser, MD
Deputy Editor
Wenliang Chen, MD, PhD


Appendicitis, an inflammation of the vestigial vermiform appendix, is one of the most common causes of the acute abdomen and one of the most frequent indications for an emergent abdominal surgical procedure worldwide [1,2].

The clinical manifestations and differential diagnosis of appendicitis in adults will be reviewed here. The diagnostic evaluation and management of appendicitis in adults and appendicitis in pregnancy and children are discussed separately. (See "Acute appendicitis in adults: Diagnostic evaluation" and "Management of acute appendicitis in adults" and "Acute appendicitis in pregnancy" and "Acute appendicitis in children: Clinical manifestations and diagnosis".)


The vermiform appendix is located at the base of the cecum, near the ileocecal valve where the taenia coli converge on the cecum (figure 1) [3,4]. The appendix is a true diverticulum of the cecum. In contrast to acquired diverticular disease, which consists of a protuberance of a subset of the enteric wall layers, the appendiceal wall contains all of the layers of the colonic wall: mucosa, submucosa, muscularis (longitudinal and circular), and the serosal covering [5].

The appendiceal orifice opens into the cecum. Its blood supply, the appendiceal artery, is a terminal branch of the ileocolic artery, which traverses the length of the mesoappendix and terminates at the tip of the organ (figure 2) [4].

The attachment of the appendix to the base of the cecum is constant. However, the tip may migrate to the retrocecal, subcecal, preileal, postileal, and pelvic positions. These normal anatomic variations can complicate the diagnosis as the site of pain and findings on the clinical examination will reflect the anatomic position of the appendix.

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Literature review current through: Nov 2017. | This topic last updated: Jul 12, 2017.
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  1. Williams GR. Presidential Address: a history of appendicitis. With anecdotes illustrating its importance. Ann Surg 1983; 197:495.
  2. Fitz RH. Perforating inflammation of the vermiform appendix with special reference to its early diagnosis and treatment. Am J Med Sci 1886; 92:321.
  3. Jaffe BM, Berger DH. The appendix. In: Schwartz's Principles of Surgery, 8th ed, Schwartz SI, Brunicardi CF (Eds), McGraw-Hill Companies, New York 2005.
  4. Buschard K, Kjaeldgaard A. Investigation and analysis of the position, fixation, length and embryology of the vermiform appendix. Acta Chir Scand 1973; 139:293.
  5. Mulholland MW, Lillemoe KD, Doherty GM, et al.. Greenfield's Surgery: Scientific Principles and Practice, 4th ed, Lippincott Williams & Wilkins, Philadelphia 2005.
  6. Kumar V, Abbas AK, Fausto N. Robbins & Cotran Pathologic Basis of Disease, 7th ed, Saunders Elsevier, Philadelphia 2007.
  7. Addiss DG, Shaffer N, Fowler BS, Tauxe RV. The epidemiology of appendicitis and appendectomy in the United States. Am J Epidemiol 1990; 132:910.
  8. Birnbaum BA, Wilson SR. Appendicitis at the millennium. Radiology 2000; 215:337.
  9. Burkitt DP. The aetiology of appendicitis. Br J Surg 1971; 58:695.
  10. Butler C. Surgical pathology of acute appendicitis. Hum Pathol 1981; 12:870.
  11. Miranda R, Johnston AD, O'Leary JP. Incidental appendectomy: frequency of pathologic abnormalities. Am Surg 1980; 46:355.
  12. Arnbjörnsson E, Bengmark S. Obstruction of the appendix lumen in relation to pathogenesis of acute appendicitis. Acta Chir Scand 1983; 149:789.
  13. Nitecki S, Karmeli R, Sarr MG. Appendiceal calculi and fecaliths as indications for appendectomy. Surg Gynecol Obstet 1990; 171:185.
  14. Jones BA, Demetriades D, Segal I, Burkitt DP. The prevalence of appendiceal fecaliths in patients with and without appendicitis. A comparative study from Canada and South Africa. Ann Surg 1985; 202:80.
  15. Lau WY, Teoh-Chan CH, Fan ST, et al. The bacteriology and septic complication of patients with appendicitis. Ann Surg 1984; 200:576.
  16. Bennion RS, Baron EJ, Thompson JE Jr, et al. The bacteriology of gangrenous and perforated appendicitis--revisited. Ann Surg 1990; 211:165.
  17. Temple CL, Huchcroft SA, Temple WJ. The natural history of appendicitis in adults. A prospective study. Ann Surg 1995; 221:278.
  18. Lee SL, Walsh AJ, Ho HS. Computed tomography and ultrasonography do not improve and may delay the diagnosis and treatment of acute appendicitis. Arch Surg 2001; 136:556.
  19. Rao PM, Rhea JT, Novelline RA, et al. Helical CT technique for the diagnosis of appendicitis: prospective evaluation of a focused appendix CT examination. Radiology 1997; 202:139.
  20. Chung CH, Ng CP, Lai KK. Delays by patients, emergency physicians, and surgeons in the management of acute appendicitis: retrospective study. Hong Kong Med J 2000; 6:254.
  21. Guidry SP, Poole GV. The anatomy of appendicitis. Am Surg 1994; 60:68.
  22. Takada T, Nishiwaki H, Yamamoto Y, et al. The Role of Digital Rectal Examination for Diagnosis of Acute Appendicitis: A Systematic Review and Meta-Analysis. PLoS One 2015; 10:e0136996.
  23. McBurney, C. Experience with early operative interference in cases of disease of the vermiform appendix. NY Med J 1889; 50:676.
  24. Golledge J, Toms AP, Franklin IJ, et al. Assessment of peritonism in appendicitis. Ann R Coll Surg Engl 1996; 78:11.
  25. Andersson RE, Hugander AP, Ghazi SH, et al. Diagnostic value of disease history, clinical presentation, and inflammatory parameters of appendicitis. World J Surg 1999; 23:133.
  26. Lane R, Grabham J. A useful sign for the diagnosis of peritoneal irritation in the right iliac fossa. Ann R Coll Surg Engl 1997; 79:128.
  27. Rovsing, NT. Indirektes Hervorrufen des typischen Schmerzes an McBurney's Punkt. Ein Beitrag zur diagnostik der Appendicitis und Typhlitis. Zentralblatt für Chirurgie, Leipzig, 1907; 34:1257.
  28. Izbicki JR, Knoefel WT, Wilker DK, et al. Accurate diagnosis of acute appendicitis: a retrospective and prospective analysis of 686 patients. Eur J Surg 1992; 158:227.
  29. Alshehri MY, Ibrahim A, Abuaisha N, et al. Value of rebound tenderness in acute appendicitis. East Afr Med J 1995; 72:504.
  30. Jahn H, Mathiesen FK, Neckelmann K, et al. Comparison of clinical judgment and diagnostic ultrasonography in the diagnosis of acute appendicitis: experience with a score-aided diagnosis. Eur J Surg 1997; 163:433.
  31. Berry J Jr, Malt RA. Appendicitis near its centenary. Ann Surg 1984; 200:567.
  32. John H, Neff U, Kelemen M. Appendicitis diagnosis today: clinical and ultrasonic deductions. World J Surg 1993; 17:243.
  33. Cope Z, Silen W. Cope's Early Diagnosis of the Acute Abdomen, 19th ed, Oxford University Press, New York 1996. p.70.
  34. Coleman C, Thompson JE Jr, Bennion RS, Schmit PJ. White blood cell count is a poor predictor of severity of disease in the diagnosis of appendicitis. Am Surg 1998; 64:983.
  35. Tehrani HY, Petros JG, Kumar RR, Chu Q. Markers of severe appendicitis. Am Surg 1999; 65:453.
  36. Thompson MM, Underwood MJ, Dookeran KA, et al. Role of sequential leucocyte counts and C-reactive protein measurements in acute appendicitis. Br J Surg 1992; 79:822.
  37. Grönroos JM, Grönroos P. Leucocyte count and C-reactive protein in the diagnosis of acute appendicitis. Br J Surg 1999; 86:501.
  38. Guraya SY, Al-Tuwaijri TA, Khairy GA, Murshid KR. Validity of leukocyte count to predict the severity of acute appendicitis. Saudi Med J 2005; 26:1945.
  39. Sand M, Bechara FG, Holland-Letz T, et al. Diagnostic value of hyperbilirubinemia as a predictive factor for appendiceal perforation in acute appendicitis. Am J Surg 2009; 198:193.
  40. Rao PM, Rhea JT, Novelline RA. Sensitivity and specificity of the individual CT signs of appendicitis: experience with 200 helical appendiceal CT examinations. J Comput Assist Tomogr 1997; 21:686.
  41. Whitley S, Sookur P, McLean A, Power N. The appendix on CT. Clin Radiol 2009; 64:190.
  42. Choi D, Park H, Lee YR, et al. The most useful findings for diagnosing acute appendicitis on contrast-enhanced helical CT. Acta Radiol 2003; 44:574.
  43. Kessler N, Cyteval C, Gallix B, et al. Appendicitis: evaluation of sensitivity, specificity, and predictive values of US, Doppler US, and laboratory findings. Radiology 2004; 230:472.
  44. Jeffrey RB Jr, Laing FC, Townsend RR. Acute appendicitis: sonographic criteria based on 250 cases. Radiology 1988; 167:327.
  45. Spalluto LB, Woodfield CA, DeBenedectis CM, Lazarus E. MR imaging evaluation of abdominal pain during pregnancy: appendicitis and other nonobstetric causes. Radiographics 2012; 32:317.
  46. Oto A, Ernst RD, Ghulmiyyah LM, et al. MR imaging in the triage of pregnant patients with acute abdominal and pelvic pain. Abdom Imaging 2009; 34:243.
  47. Pedrosa I, Levine D, Eyvazzadeh AD, et al. MR imaging evaluation of acute appendicitis in pregnancy. Radiology 2006; 238:891.
  48. Lee TH, Kim JO, Kim JJ, et al. A case of intussuscepted Meckel's diverticulum. World J Gastroenterol 2009; 15:5109.
  49. Banli O, Karakoyun R, Altun H. Ileo-ileal intussusception due to inverted Meckel's diverticulum. Acta Chir Belg 2009; 109:516.