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Management of acute appendicitis in adults

Douglas Smink, MD, MPH
David I Soybel, MD
Section Editor
Martin Weiser, MD
Deputy Editor
Wenliang Chen, MD, PhD


The goal of management of acute appendicitis is early diagnosis and prompt operative intervention. However, this goal is not always easily accomplished since many patients do not seek medical attention in a timely manner and the diagnosis of appendicitis can be difficult [1]. Many surgeons use an aggressive approach, accepting a certain number of negative appendectomies, traditionally 15 percent, although the use of advanced abdominal imaging appears to have reduced the negative appendectomy rate to less than 10 percent [2].

The management of appendicitis in adults will be reviewed here. The diagnosis and differential diagnosis of appendicitis, appendicitis in pregnancy, and the diagnosis and differential diagnosis of abdominal pain in general are discussed separately. (See "Acute appendicitis in adults: Clinical manifestations and differential diagnosis" and "Acute appendicitis in pregnancy" and "Evaluation of the adult with abdominal pain" and "Causes of abdominal pain in adults".)


Appendectomy remains the standard of care for most patients with uncomplicated acute appendicitis. An alternative strategy is antibiotic therapy, with appendectomy reserved for those who do not respond to this treatment or those who develop complicated appendicitis. Some theorize that perforated and nonperforated appendicitis could have different patterns and pathological processes [3]. There may be a subset of patients who will respond to nonoperative management and for whom the risk of recurrent acute appendicitis are less than the potential risks associated with appendectomy. However, given that the subset of patients least likely to fail initial nonoperative management (37 percent in the meta-analysis below) has not been definitively determined, we continue to recommend appendectomy as the preferred treatment for those with acute appendicitis, complicated or uncomplicated, for the following reasons:

Appendectomy can generally be performed with low morbidity and very low mortality.

Preoperative abdominal computed tomography (CT) interpreted as uncomplicated appendicitis cannot exclude the possibility of complicated disease. In one trial, among patients in the appendectomy arm, 20 percent had complicated appendicitis identified at the time of surgery [4].

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Literature review current through: Sep 2017. | This topic last updated: Jun 26, 2017.
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  1. Pittman-Waller VA, Myers JG, Stewart RM, et al. Appendicitis: why so complicated? Analysis of 5755 consecutive appendectomies. Am Surg 2000; 66:548.
  2. SCOAP Collaborative, Cuschieri J, Florence M, et al. Negative appendectomy and imaging accuracy in the Washington State Surgical Care and Outcomes Assessment Program. Ann Surg 2008; 248:557.
  3. Andersson R, Hugander A, Thulin A, et al. Indications for operation in suspected appendicitis and incidence of perforation. BMJ 1994; 308:107.
  4. Vons C, Barry C, Maitre S, et al. Amoxicillin plus clavulanic acid versus appendicectomy for treatment of acute uncomplicated appendicitis: an open-label, non-inferiority, randomised controlled trial. Lancet 2011; 377:1573.
  5. Singh JP, Mariadason JG. Role of the faecolith in modern-day appendicitis. Ann R Coll Surg Engl 2013; 95:48.
  6. Nitecki S, Karmeli R, Sarr MG. Appendiceal calculi and fecaliths as indications for appendectomy. Surg Gynecol Obstet 1990; 171:185.
  7. Marudanayagam R, Williams GT, Rees BI. Review of the pathological results of 2660 appendicectomy specimens. J Gastroenterol 2006; 41:745.
  8. Kırkıl C, Yiğit MV, Aygen E. Long-term results of nonoperative treatment for uncomplicated acute appendicitis. Turk J Gastroenterol 2014; 25:393.
  9. McCutcheon BA, Chang DC, Marcus LP, et al. Long-term outcomes of patients with nonsurgically managed uncomplicated appendicitis. J Am Coll Surg 2014; 218:905.
  10. Carpenter SG, Chapital AB, Merritt MV, Johnson DJ. Increased risk of neoplasm in appendicitis treated with interval appendectomy: single-institution experience and literature review. Am Surg 2012; 78:339.
  11. Chandrasegaram MD, Rothwell LA, An EI, Miller RJ. Pathologies of the appendix: a 10-year review of 4670 appendicectomy specimens. ANZ J Surg 2012; 82:844.
  12. Sartelli M, Viale P, Catena F, et al. 2013 WSES guidelines for management of intra-abdominal infections. World J Emerg Surg 2013; 8:3.
  13. Chhabra KR, Sacks GD, Dimick JB. Surgical Decision Making: Challenging Dogma and Incorporating Patient Preferences. JAMA 2017; 317:357.
  14. Hansson J, Körner U, Khorram-Manesh A, et al. Randomized clinical trial of antibiotic therapy versus appendicectomy as primary treatment of acute appendicitis in unselected patients. Br J Surg 2009; 96:473.
  15. Eriksson S, Granström L. Randomized controlled trial of appendicectomy versus antibiotic therapy for acute appendicitis. Br J Surg 1995; 82:166.
  16. Styrud J, Eriksson S, Nilsson I, et al. Appendectomy versus antibiotic treatment in acute appendicitis. a prospective multicenter randomized controlled trial. World J Surg 2006; 30:1033.
  17. Turhan AN, Kapan S, Kütükçü E, et al. Comparison of operative and non operative management of acute appendicitis. Ulus Travma Acil Cerrahi Derg 2009; 15:459.
  18. Salminen P, Paajanen H, Rautio T, et al. Antibiotic Therapy vs Appendectomy for Treatment of Uncomplicated Acute Appendicitis: The APPAC Randomized Clinical Trial. JAMA 2015; 313:2340.
  19. Wilms IM, de Hoog DE, de Visser DC, Janzing HM. Appendectomy versus antibiotic treatment for acute appendicitis. Cochrane Database Syst Rev 2011; :CD008359.
  20. Varadhan KK, Neal KR, Lobo DN. Safety and efficacy of antibiotics compared with appendicectomy for treatment of uncomplicated acute appendicitis: meta-analysis of randomised controlled trials. BMJ 2012; 344:e2156.
  21. Antibiotic therapy for acute appendicitis in adults. Fewer immediate complications than with surgery, but more subsequent failures. Prescrire Int 2014; 23:158.
  22. Sallinen V, Akl EA, You JJ, et al. Meta-analysis of antibiotics versus appendicectomy for non-perforated acute appendicitis. Br J Surg 2016; 103:656.
  23. Harnoss JC, Zelienka I, Probst P, et al. Antibiotics Versus Surgical Therapy for Uncomplicated Appendicitis: Systematic Review and Meta-analysis of Controlled Trials (PROSPERO 2015: CRD42015016882). Ann Surg 2017; 265:889.
  24. Di Saverio S, Sibilio A, Giorgini E, et al. The NOTA Study (Non Operative Treatment for Acute Appendicitis): prospective study on the efficacy and safety of antibiotics (amoxicillin and clavulanic acid) for treating patients with right lower quadrant abdominal pain and long-term follow-up of conservatively treated suspected appendicitis. Ann Surg 2014; 260:109.
  25. Flum DR. Clinical practice. Acute appendicitis--appendectomy or the "antibiotics first" strategy. N Engl J Med 2015; 372:1937.
  26. Faiz O, Clark J, Brown T, et al. Traditional and laparoscopic appendectomy in adults: outcomes in English NHS hospitals between 1996 and 2006. Ann Surg 2008; 248:800.
  27. Sporn E, Petroski GF, Mancini GJ, et al. Laparoscopic appendectomy--is it worth the cost? Trend analysis in the US from 2000 to 2005. J Am Coll Surg 2009; 208:179.
  28. Nguyen NT, Zainabadi K, Mavandadi S, et al. Trends in utilization and outcomes of laparoscopic versus open appendectomy. Am J Surg 2004; 188:813.
  29. Brügger L, Rosella L, Candinas D, Güller U. Improving outcomes after laparoscopic appendectomy: a population-based, 12-year trend analysis of 7446 patients. Ann Surg 2011; 253:309.
  30. Sauerland S, Jaschinski T, Neugebauer EA. Laparoscopic versus open surgery for suspected appendicitis. Cochrane Database Syst Rev 2010; :CD001546.
  31. Andersson RE. Short-term complications and long-term morbidity of laparoscopic and open appendicectomy in a national cohort. Br J Surg 2014; 101:1135.
  32. McCahill LE, Pellegrini CA, Wiggins T, Helton WS. A clinical outcome and cost analysis of laparoscopic versus open appendectomy. Am J Surg 1996; 171:533.
  33. Andersson RE, Hugander A, Thulin AJ. Diagnostic accuracy and perforation rate in appendicitis: association with age and sex of the patient and with appendicectomy rate. Eur J Surg 1992; 158:37.
  34. Körner H, Söndenaa K, Söreide JA, et al. Incidence of acute nonperforated and perforated appendicitis: age-specific and sex-specific analysis. World J Surg 1997; 21:313.
  35. Moberg AC, Ahlberg G, Leijonmarck CE, et al. Diagnostic laparoscopy in 1043 patients with suspected acute appendicitis. Eur J Surg 1998; 164:833.
  36. Enochsson L, Hellberg A, Rudberg C, et al. Laparoscopic vs open appendectomy in overweight patients. Surg Endosc 2001; 15:387.
  37. Golub R, Siddiqui F, Pohl D. Laparoscopic versus open appendectomy: a metaanalysis. J Am Coll Surg 1998; 186:545.
  38. Mason RJ, Moazzez A, Moroney JR, Katkhouda N. Laparoscopic vs open appendectomy in obese patients: outcomes using the American College of Surgeons National Surgical Quality Improvement Program database. J Am Coll Surg 2012; 215:88.
  39. Harrell AG, Lincourt AE, Novitsky YW, et al. Advantages of laparoscopic appendectomy in the elderly. Am Surg 2006; 72:474.
  40. Garst GC, Moore EE, Banerjee MN, et al. Acute appendicitis: a disease severity score for the acute care surgeon. J Trauma Acute Care Surg 2013; 74:32.
  41. Andersen BR, Kallehave FL, Andersen HK. Antibiotics versus placebo for prevention of postoperative infection after appendicectomy. Cochrane Database Syst Rev 2005; :CD001439.
  42. Fry DE. Surgical site infections and the surgical care improvement project (SCIP): evolution of national quality measures. Surg Infect (Larchmt) 2008; 9:579.
  43. Bratzler DW, Houck PM, Surgical Infection Prevention Guidelines Writers Workgroup, et al. Antimicrobial prophylaxis for surgery: an advisory statement from the National Surgical Infection Prevention Project. Clin Infect Dis 2004; 38:1706.
  44. Bratzler DW, Hunt DR. The surgical infection prevention and surgical care improvement projects: national initiatives to improve outcomes for patients having surgery. Clin Infect Dis 2006; 43:322.
  45. Antimicrobial prophylaxis for surgery. Treat Guidel Med Lett 2009; 7:47.
  46. Berríos-Torres SI, Umscheid CA, Bratzler DW, et al. Centers for Disease Control and Prevention Guideline for the Prevention of Surgical Site Infection, 2017. JAMA Surg 2017; 152:784.
  47. Ciftci AO, Tanyel FC, Büyükpamukçu N, Hiçsonmez A. Comparative trial of four antibiotic combinations for perforated appendicitis in children. Eur J Surg 1997; 163:591.
  48. Schropp KP, Kaplan S, Golladay ES, et al. A randomized clinical trial of ampicillin, gentamicin and clindamycin versus cefotaxime and clindamycin in children with ruptured appendicitis. Surg Gynecol Obstet 1991; 172:351.
  49. Frutos MD, Abrisqueta J, Lujan J, et al. Randomized prospective study to compare laparoscopic appendectomy versus umbilical single-incision appendectomy. Ann Surg 2013; 257:413.
  50. Kim JH, Kim HY, Park SK, et al. Single-incision Laparoscopic Appendectomy Versus Conventional Laparoscopic Appendectomy: Experiences From 1208 Cases of Single-incision Laparoscopic Appendectomy. Experiences From 1208 Cases of Single-incision Laparoscopic Appendectomy. Ann Surg 2015; 262:1054.
  51. Mangi AA, Berger DL. Stump appendicitis. Am Surg 2000; 66:739.
  52. Arnbjörnsson E. Invagination of the appendiceal stump for the reduction of peritoneal bacterial contamination. Curr Surg 1985; 42:184.
  53. Watters DA, Walker MA, Abernethy BC. The appendix stump: should it be invaginated? Ann R Coll Surg Engl 1984; 66:92.
  54. Engström L, Fenyö G. Appendicectomy: assessment of stump invagination versus simple ligation: a prospective, randomized trial. Br J Surg 1985; 72:971.
  55. Street D, Bodai BI, Owens LJ, et al. Simple ligation vs stump inversion in appendectomy. Arch Surg 1988; 123:689.
  56. Poole GV. Management of the difficult appendiceal stump: how I do it. Am Surg 1993; 59:624.
  57. Temple CL, Huchcroft SA, Temple WJ. The natural history of appendicitis in adults. A prospective study. Ann Surg 1995; 221:278.
  58. Greenall MJ, Evans M, Pollock AV. Should you drain a perforated appendix? Br J Surg 1978; 65:880.
  59. Petrowsky H, Demartines N, Rousson V, Clavien PA. Evidence-based value of prophylactic drainage in gastrointestinal surgery: a systematic review and meta-analyses. Ann Surg 2004; 240:1074.
  60. Cheng Y, Zhou S, Zhou R, et al. Abdominal drainage to prevent intra-peritoneal abscess after open appendectomy for complicated appendicitis. Cochrane Database Syst Rev 2015; :CD010168.
  61. Lemieur TP, Rodriguez JL, Jacobs DM, et al. Wound management in perforated appendicitis. Am Surg 1999; 65:439.
  62. Cohn SM, Giannotti G, Ong AW, et al. Prospective randomized trial of two wound management strategies for dirty abdominal wounds. Ann Surg 2001; 233:409.
  63. Brasel KJ, Borgstrom DC, Weigelt JA. Cost-utility analysis of contaminated appendectomy wounds. J Am Coll Surg 1997; 184:23.
  64. Skoubo-Kristensen E, Hvid I. The appendiceal mass: results of conservative management. Ann Surg 1982; 196:584.
  65. Nitecki S, Assalia A, Schein M. Contemporary management of the appendiceal mass. Br J Surg 1993; 80:18.
  66. Oliak D, Yamini D, Udani VM, et al. Initial nonoperative management for periappendiceal abscess. Dis Colon Rectum 2001; 44:936.
  67. Bagi P, Dueholm S. Nonoperative management of the ultrasonically evaluated appendiceal mass. Surgery 1987; 101:602.
  68. Jeffrey RB Jr, Federle MP, Tolentino CS. Periappendiceal inflammatory masses: CT-directed management and clinical outcome in 70 patients. Radiology 1988; 167:13.
  69. Gee D, Babineau TJ. The optimal management of adult patients presenting with appendiceal abscess: "conservative" vs immediate operative management. Curr Surg 2004; 61:524.
  70. Siewert B, Raptopoulos V. CT of the acute abdomen: findings and impact on diagnosis and treatment. AJR Am J Roentgenol 1994; 163:1317.
  71. Brown CV, Abrishami M, Muller M, Velmahos GC. Appendiceal abscess: immediate operation or percutaneous drainage? Am Surg 2003; 69:829.
  72. Fagenholz PJ, Peev MP, Thabet A, et al. Abscess due to perforated appendicitis: factors associated with successful percutaneous drainage. Am J Surg 2016; 212:794.
  73. Nguyen DB, Silen W, Hodin RA. Interval appendectomy in the laparoscopic era. J Gastrointest Surg 1999; 3:189.
  74. Eriksson S, Tisell A, Granström L. Ultrasonographic findings after conservative treatment of acute appendicitis and open appendicectomy. Acta Radiol 1995; 36:173.
  75. Blair NP, Bugis SP, Turner LJ, MacLeod MM. Review of the pathologic diagnoses of 2,216 appendectomy specimens. Am J Surg 1993; 165:618.
  76. Deans GT, Spence RA. Neoplastic lesions of the appendix. Br J Surg 1995; 82:299.
  77. Wright GP, Mater ME, Carroll JT, et al. Is there truly an oncologic indication for interval appendectomy? Am J Surg 2015; 209:442.
  78. Andersson RE, Petzold MG. Nonsurgical treatment of appendiceal abscess or phlegmon: a systematic review and meta-analysis. Ann Surg 2007; 246:741.
  79. Kaminski A, Liu IL, Applebaum H, et al. Routine interval appendectomy is not justified after initial nonoperative treatment of acute appendicitis. Arch Surg 2005; 140:897.
  80. Rucinski J, Fabian T, Panagopoulos G, et al. Gangrenous and perforated appendicitis: a meta-analytic study of 2532 patients indicates that the incision should be closed primarily. Surgery 2000; 127:136.
  81. Fleming FJ, Kim MJ, Messing S, et al. Balancing the risk of postoperative surgical infections: a multivariate analysis of factors associated with laparoscopic appendectomy from the NSQIP database. Ann Surg 2010; 252:895.
  82. Flum DR, Morris A, Koepsell T, Dellinger EP. Has misdiagnosis of appendicitis decreased over time? A population-based analysis. JAMA 2001; 286:1748.
  83. Wang Y, Reen DJ, Puri P. Is a histologically normal appendix following emergency appendicectomy alway normal? Lancet 1996; 347:1076.
  84. Grunewald B, Keating J. Should the 'normal' appendix be removed at operation for appendicitis? J R Coll Surg Edinb 1993; 38:158.
  85. Chiarugi M, Buccianti P, Decanini L, et al. "What you see is not what you get". A plea to remove a 'normal' appendix during diagnostic laparoscopy. Acta Chir Belg 2001; 101:243.
  86. Greason KL, Rappold JF, Liberman MA. Incidental laparoscopic appendectomy for acute right lower quadrant abdominal pain. Its time has come. Surg Endosc 1998; 12:223.
  87. Teh SH, O'Ceallaigh S, Mckeon JG, et al. Should an appendix that looks 'normal' be removed at diagnostic laparoscopy for acute right iliac fossa pain? Eur J Surg 2000; 166:388.
  88. Watters JM, Blakslee JM, March RJ, Redmond ML. The influence of age on the severity of peritonitis. Can J Surg 1996; 39:142.
  89. Addiss DG, Shaffer N, Fowler BS, Tauxe RV. The epidemiology of appendicitis and appendectomy in the United States. Am J Epidemiol 1990; 132:910.
  90. Horattas MC, Guyton DP, Wu D. A reappraisal of appendicitis in the elderly. Am J Surg 1990; 160:291.
  91. Paajanen H, Kettunen J, Kostiainen S. Emergency appendectomies in patients over 80 years. Am Surg 1994; 60:950.
  92. Hui TT, Major KM, Avital I, et al. Outcome of elderly patients with appendicitis: effect of computed tomography and laparoscopy. Arch Surg 2002; 137:995.
  93. Guller U, Hervey S, Purves H, et al. Laparoscopic versus open appendectomy: outcomes comparison based on a large administrative database. Ann Surg 2004; 239:43.
  94. Flum DR, Steinberg SD, Sarkis AY, Wallack MK. Appendicitis in patients with acquired immunodeficiency syndrome. J Am Coll Surg 1997; 184:481.
  95. Bova R, Meagher A. Appendicitis in HIV-positive patients. Aust N Z J Surg 1998; 68:337.
  96. Whitney TM, Macho JR, Russell TR, et al. Appendicitis in acquired immunodeficiency syndrome. Am J Surg 1992; 164:467.
  97. Connor SJ, Hanna GB, Frizelle FA. Appendiceal tumors: retrospective clinicopathologic analysis of appendiceal tumors from 7,970 appendectomies. Dis Colon Rectum 1998; 41:75.
  98. Mussack T, Schmidbauer S, Nerlich A, et al. [Chronic appendicitis as an independent clinical entity]. Chirurg 2002; 73:710.
  99. Leardi S, Delmonaco S, Ventura T, et al. [Recurrent abdominal pain and "chronic appendicitis"]. Minerva Chir 2000; 55:39.
  100. Sar S, Mahawar KK, Marsh R, Small PK. Recurrent appendicitis following successful conservative management of an appendicular mass in association with a foreign body: a case report. Cases J 2009; 2:7776.