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Appendicitis Differential Diagnoses

  • Author: Sandy Craig, MD; Chief Editor: Barry E Brenner, MD, PhD, FACEP  more...
 
Updated: Dec 27, 2015
 
 

Diagnostic Considerations

The overall accuracy for diagnosing acute appendicitis is approximately 80%, which corresponds to a mean negative appendectomy rate of 20%. Diagnostic accuracy varies by sex, with a range of 78-92% in male patients and 58-85% in female patients.

The classic history of anorexia and periumbilical pain followed by nausea, right lower quadrant (RLQ) pain, and vomiting occurs in only 50% of cases. Vomiting that precedes pain is suggestive of intestinal obstruction, and the diagnosis of appendicitis should be reconsidered.

The differential diagnosis of appendicitis is often a clinical challenge because appendicitis can mimic several abdominal conditions (see Differentials).[14] Patients with many other disorders present with symptoms similar to those of appendicitis, such as the following:

Other problems that should be considered in a patient with suspected appendicitis include appendiceal stump appendicitis, typhlitis, epiploic appendagitis, psoas abscess, and yersiniosis.

Misdiagnosis in women of childbearing age

Appendicitis is misdiagnosed in 33% of nonpregnant women of childbearing age. The most frequent misdiagnoses are PID, followed by gastroenteritis and urinary tract infection. In distinguishing appendiceal pain from that of PID, anorexia and onset of pain more than 14 days after menses suggests appendicitis. Previous PID, vaginal discharge, or urinary symptoms indicates PID. On physical examination, tenderness outside the RLQ, cervical motion tenderness, vaginal discharge, and positive urinalysis support the diagnosis of PID.

Although negative appendectomy does not appear to adversely affect maternal or fetal health, diagnostic delay with perforation does increase fetal and maternal morbidity. Therefore, aggressive evaluation of the appendix is warranted in pregnant women.

The level of urinary beta–human chorionic gonadotropin (beta-hCG) is useful in differentiating appendicitis from early ectopic pregnancy. However, with regard to the WBC count, physiologic leukocytosis during pregnancy makes this study less useful in the diagnosis than at other times, and no reliable distinguishing WBC parameters are cited in the literature.

Misdiagnosis in children

Appendicitis is misdiagnosed in 25-30% of children, and the rate of initial misdiagnosis is inversely related to the age of the patient. The most common misdiagnosis is gastroenteritis, followed by upper respiratory infection and lower respiratory infection.

Children with misdiagnosed appendicitis are more likely than their counterparts to have vomiting before pain onset, diarrhea, constipation, dysuria, signs and symptoms of upper respiratory infection, and lethargy or irritability. Physical findings less likely to be documented in children with a misdiagnosis than in others include bowel sounds; peritoneal signs; rectal findings; and ear, nose, and throat findings.

Considerations in elderly patients

Appendicitis in patients older than 60 years accounts for 10% of all appendectomies. The incidence of misdiagnosis is increased in elderly patients.

Older patients tend to seek medical attention later in the course of illness; therefore, a duration of symptoms in excess of 24-48 hours should not dissuade the clinician from the diagnosis. In patients with comorbid conditions, diagnostic delay is correlated with increased morbidity and mortality.

Differential Diagnoses

 
 
Contributor Information and Disclosures
Author

Sandy Craig, MD Residency Program Director, Carolinas Medical Center; Associate Professor, Department of Emergency Medicine, University of North Carolina at Chapel Hill School of Medicine

Sandy Craig, MD is a member of the following medical societies: Alpha Omega Alpha, Society for Academic Emergency Medicine

Disclosure: Nothing to disclose.

Chief Editor

Barry E Brenner, MD, PhD, FACEP Professor of Emergency Medicine, Professor of Internal Medicine, Program Director for Emergency Medicine, Case Medical Center, University Hospitals, Case Western Reserve University School of Medicine

Barry E Brenner, MD, PhD, FACEP is a member of the following medical societies: Alpha Omega Alpha, American Heart Association, American Thoracic Society, Arkansas Medical Society, New York Academy of Medicine, New York Academy of Sciences, Society for Academic Emergency Medicine, American Academy of Emergency Medicine, American College of Chest Physicians, American College of Emergency Physicians, American College of Physicians

Disclosure: Nothing to disclose.

Acknowledgements

Eugene Hardin, MD, FAAEM, FACEP Former Chair and Associate Professor, Department of Emergency Medicine, Charles Drew University of Medicine and Science; Former Chair, Department of Emergency Medicine, Martin Luther King Jr/Drew Medical Center

Disclosure: Nothing to disclose.

William Lober, MD, MS Associate Professor, Health Informatics and Global Health, Schools of Medicine, Nursing, and Public Health, University of Washington

Disclosure: Nothing to disclose.

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Medscape Salary Employment

References
  1. Polites SF, Mohamed MI, Habermann EB, et al. A simple algorithm reduces computed tomography use in the diagnosis of appendicitis in children. Surgery. 2014 Jun 19. [Medline].

  2. Douglas D. Algorithm cuts pediatric CT use in suspected appendicitis. Reuters Health Information. July 10, 2014. [Full Text].

  3. Yeh B. Evidence-based emergency medicine/rational clinical examination abstract. Does this adult patient have appendicitis?. Ann Emerg Med. 2008 Sep. 52(3):301-3. [Medline].

  4. Markle GB 4th. Heel-drop jarring test for appendicitis. Arch Surg. 1985 Feb. 120(2):243. [Medline].

  5. Thimsen DA, Tong GK, Gruenberg JC. Prospective evaluation of C-reactive protein in patients suspected to have acute appendicitis. Am Surg. 1989 Jul. 55(7):466-8. [Medline].

  6. de Carvalho BR, Diogo-Filho A, Fernandes C, Barra CB. [Leukocyte count, C reactive protein, alpha-1 acid glycoprotein and erythrocyte sedimentation rate in acute appendicitis]. Arq Gastroenterol. 2003 Jan-Mar. 40(1):25-30. [Medline].

  7. Albu E, Miller BM, Choi Y, et al. Diagnostic value of C-reactive protein in acute appendicitis. Dis Colon Rectum. 1994 Jan. 37(1):49-51. [Medline].

  8. Bolandparvaz S, Vasei M, Owji AA, Ata-Ee N, Amin A, Daneshbod Y, et al. Urinary 5-hydroxy indole acetic acid as a test for early diagnosis of acute appendicitis. Clin Biochem. 2004 Nov. 37(11):985-9. [Medline].

  9. Kim K, Kim YH, Kim SY, Kim S, Lee YJ, Kim KP, et al. Low-dose abdominal CT for evaluating suspected appendicitis. N Engl J Med. 2012 Apr 26. 366(17):1596-605. [Medline].

  10. Howell JM, Eddy OL, Lukens TW, Thiessen ME, Weingart SD, Decker WW. Clinical policy: Critical issues in the evaluation and management of emergency department patients with suspected appendicitis. Ann Emerg Med. 2010 Jan. 55(1):71-116. [Medline].

  11. [Guideline] National Guideline Clearinghouse (NGC). Guideline summary: Clinical policy: critical issues in the evaluation and management of emergency department patients with suspected appendicitis. National Guideline Clearinghouse (NGC), Rockville (MD). Available at http://guideline.gov/content.aspx?id=15598. Accessed: November 18, 2013.

  12. Barloon TJ, Brown BP, Abu-Yousef MM, Warnock N, Berbaum KS. Sonography of acute appendicitis in pregnancy. Abdom Imaging. 1995 Mar-Apr. 20(2):149-51. [Medline].

  13. Manterola C, Vial M, Moraga J, Astudillo P. Analgesia in patients with acute abdominal pain. Cochrane Database Syst Rev. 2011 Jan 19. 1:CD005660. [Medline].

  14. Karamanakos SN, Sdralis E, Panagiotopoulos S, Kehagias I. Laparoscopy in the emergency setting: a retrospective review of 540 patients with acute abdominal pain. Surg Laparosc Endosc Percutan Tech. 2010 Apr. 20(2):119-24. [Medline].

  15. Niwa H, Hiramatsu T. A rare presentation of appendiceal diverticulitis associated with pelvic pseudocyst. World J Gastroenterol. 2008 Feb 28. 14(8):1293-5. [Medline]. [Full Text].

  16. Place RC. Acute urinary retention in a 9-year-old child: an atypical presentation of acute appendicitis. J Emerg Med. 2006 Aug. 31(2):173-5. [Medline].

  17. Oto A, Ernst RD, Mileski WJ, Nishino TK, Le O, Wolfe GC, et al. Localization of appendix with MDCT and influence of findings on choice of appendectomy incision. AJR Am J Roentgenol. 2006 Oct. 187(4):987-90. [Medline].

  18. Sedlak M, Wagner OJ, Wild B, Papagrigoriades S, Exadaktylos AK. Is there still a role for rectal examination in suspected appendicitis in adults?. Am J Emerg Med. 2008 Mar. 26(3):359-60. [Medline].

  19. Alvarado A. A practical score for the early diagnosis of acute appendicitis. Ann Emerg Med. 1986 May. 15(5):557-64. [Medline].

  20. Schneider C, Kharbanda A, Bachur R. Evaluating appendicitis scoring systems using a prospective pediatric cohort. Ann Emerg Med. 2007 Jun. 49(6):778-84, 784.e1. [Medline].

  21. Schneider C, Kharbanda A, Bachur R. Evaluating appendicitis scoring systems using a prospective pediatric cohort. Ann Emerg Med. 2007 Jun. 49(6):778-84, 784.e1. [Medline].

  22. Migraine S, Atri M, Bret PM, Lough JO, Hinchey JE. Spontaneously resolving acute appendicitis: clinical and sonographic documentation. Radiology. 1997 Oct. 205(1):55-8. [Medline].

  23. Cobben LP, de Van Otterloo AM, Puylaert JB. Spontaneously resolving appendicitis: frequency and natural history in 60 patients. Radiology. 2000 May. 215(2):349-52. [Medline].

  24. Dueholm S, Bagi P, Bud M. Laboratory aid in the diagnosis of acute appendicitis. A blinded, prospective trial concerning diagnostic value of leukocyte count, neutrophil differential count, and C-reactive protein. Dis Colon Rectum. 1989 Oct. 32(10):855-9. [Medline].

  25. Gurleyik E, Gurleyik G, Unalmiser S. Accuracy of serum C-reactive protein measurements in diagnosis of acute appendicitis compared with surgeon's clinical impression. Dis Colon Rectum. 1995 Dec. 38(12):1270-4. [Medline].

  26. Shakhatreh HS. The accuracy of C-reactive protein in the diagnosis of acute appendicitis compared with that of clinical diagnosis. Med Arh. 2000. 54(2):109-10. [Medline].

  27. Asfar S, Safar H, Khoursheed M, Dashti H, al-Bader A. Would measurement of C-reactive protein reduce the rate of negative exploration for acute appendicitis?. J R Coll Surg Edinb. 2000 Feb. 45(1):21-4. [Medline].

  28. Erkasap S, Ates E, Ustuner Z, Sahin A, Yilmaz S, Yasar B, et al. Diagnostic value of interleukin-6 and C-reactive protein in acute appendicitis. Swiss Surg. 2000. 6(4):169-72. [Medline].

  29. Gronroos JM, Gronroos P. Leucocyte count and C-reactive protein in the diagnosis of acute appendicitis. Br J Surg. 1999 Apr. 86(4):501-4. [Medline].

  30. Ortega-Deballon P, Ruiz de Adana-Belbel JC, Hernandez-Matias A, Garcia-Septiem J, Moreno-Azcoita M. Usefulness of laboratory data in the management of right iliac fossa pain in adults. Dis Colon Rectum. 2008 Jul. 51(7):1093-9. [Medline].

  31. Gronroos JM. Is there a role for leukocyte and CRP measurements in the diagnosis of acute appendicitis in the elderly?. Maturitas. 1999 Mar 15. 31(3):255-8. [Medline].

  32. Yang HR, Wang YC, Chung PK, et al. Role of leukocyte count, neutrophil percentage, and C-reactive protein in the diagnosis of acute appendicitis in the elderly. Am Surg. 2005 Apr. 71(4):344-7. [Medline].

  33. Gronroos JM. Do normal leucocyte count and C-reactive protein value exclude acute appendicitis in children?. Acta Paediatr. 2001 Jun. 90(6):649-51. [Medline].

  34. Stefanutti G, Ghirardo V, Gamba P. Inflammatory markers for acute appendicitis in children: are they helpful?. J Pediatr Surg. 2007 May. 42(5):773-6. [Medline].

  35. Mohammed AA, Daghman NA, Aboud SM, Oshibi HO. The diagnostic value of C-reactive protein, white blood cell count and neutrophil percentage in childhood appendicitis. Saudi Med J. 2004 Sep. 25(9):1212-5. [Medline].

  36. Yang HR, Wang YC, Chung PK, Chen WK, Jeng LB, Chen RJ. Laboratory tests in patients with acute appendicitis. ANZ J Surg. 2006 Jan-Feb. 76(1-2):71-4. [Medline].

  37. Tundidor Bermudez AM, Amado Dieguez JA, Montes de Oca Mastrapa JL. [Urological manifestations of acute appendicitis]. Arch Esp Urol. 2005 Apr. 58(3):207-12. [Medline].

  38. Rao PM, Rhea JT, Rattner DW, et al. Introduction of appendiceal CT: impact on negative appendectomy and appendiceal perforation rates. Ann Surg. 1999 Mar. 229(3):344-9. [Medline].

  39. McGory ML, Zingmond DS, Nanayakkara D, Maggard MA, Ko CY. Negative appendectomy rate: influence of CT scans. Am Surg. 2005 Oct. 71(10):803-8. [Medline].

  40. Harswick C, Uyenishi AA, Kordick MF, Chan SB. Clinical guidelines, computed tomography scan, and negative appendectomies: a case series. Am J Emerg Med. 2006 Jan. 24(1):68-72. [Medline].

  41. Frei SP, Bond WF, Bazuro RK, Richardson DM, Sierzega GM, Reed JF. Appendicitis outcomes with increasing computed tomographic scanning. Am J Emerg Med. 2008 Jan. 26(1):39-44. [Medline].

  42. Pickhardt PJ, Lawrence EM, Pooler BD, Bruce RJ. Diagnostic performance of multidetector computed tomography for suspected acute appendicitis. Ann Intern Med. 2011 Jun 21. 154(12):789-96. [Medline].

  43. Kepner AM, Bacasnot JV, Stahlman BA. Intravenous contrast alone vs intravenous and oral contrast computed tomography for the diagnosis of appendicitis in adult ED patients. Am J Emerg Med. 2012 May 23. [Medline].

  44. Brenner DJ, Hall EJ. Computed tomography--an increasing source of radiation exposure. N Engl J Med. 2007 Nov 29. 357(22):2277-84. [Medline].

  45. Zilbert NR, Stamell EF, Ezon I, Schlager A, Ginsburg HB, Nadler EP. Management and outcomes for children with acute appendicitis differ by hospital type: areas for improvement at public hospitals. Clin Pediatr (Phila). 2009 Jun. 48(5):499-504. [Medline].

  46. Doria AS, Moineddin R, Kellenberger CJ, Epelman M, Beyene J, Schuh S, et al. US or CT for Diagnosis of Appendicitis in Children and Adults? A Meta-Analysis. Radiology. 2006 Oct. 241(1):83-94. [Medline].

  47. Boggs W. Ultrasound/MRI Strategy Diagnoses Appendicitis in Kids Without Radiation. Medscape Medical News. Available at http://www.medscape.com/viewarticle/821332. Accessed: March 12, 2014.

  48. Aspelund G, Fingeret A, Gross E, Kessler D, Keung C, Thirumoorthi A, et al. Ultrasonography/MRI Versus CT for Diagnosing Appendicitis. Pediatrics. 2014 Mar 3. [Medline].

  49. Cobben LP, Groot I, Haans L, Blickman JG, Puylaert J. MRI for clinically suspected appendicitis during pregnancy. AJR Am J Roentgenol. 2004 Sep. 183(3):671-5. [Medline].

  50. Repplinger MD, Levy JF, Peethumnongsin E, et al. Systematic review and meta-analysis of the accuracy of MRI to diagnose appendicitis in the general population. J Magn Reson Imaging. 2015 Dec 22. [Medline].

  51. Thieme ME, Leeuwenburgh MM, Valdehueza ZD, Bouman DE, de Bruin IG, Schreurs WH, et al. Diagnostic accuracy and patient acceptance of MRI in children with suspected appendicitis. Eur Radiol. 2013 Oct 19. [Medline].

  52. Singer DD, Thode HC Jr, Singer AJ. Effects of pain severity and CT imaging on analgesia prescription in acute appendicitis. Am J Emerg Med. 2016 Jan. 34 (1):36-9. [Medline].

  53. Eriksson S, Granström L. Randomized controlled trial of appendicectomy versus antibiotic therapy for acute appendicitis. Br J Surg. 1995 Feb. 82(2):166-9. [Medline].

  54. 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 Jun 16. 313 (23):2340-8. [Medline].

  55. Bonadio W, Rebillot K, Ukwuoma O, Saracino C, Iskhakov A. Management of pediatric perforated appendicitis: comparing outcomes using early appendectomy vs solely medical management. Pediatr Infect Dis J. 2015 Dec 14. [Medline].

  56. Bickell NA, Aufses AH Jr, Rojas M, Bodian C. How time affects the risk of rupture in appendicitis. J Am Coll Surg. 2006 Mar. 202(3):401-6. [Medline].

  57. Abou-Nukta F, Bakhos C, Arroyo K, Koo Y, Martin J, Reinhold R, et al. Effects of delaying appendectomy for acute appendicitis for 12 to 24 hours. Arch Surg. 2006 May. 141(5):504-6; discussion 506-7. [Medline].

  58. Fair BA, Kubasiak JC, Janssen I, et al. The impact of operative timing on outcomes of appendicitis: a National Surgical Quality Improvement Project analysis. Am J Surg. 2015 Mar. 209 (3):498-502. [Medline].

  59. Boomer LA, Cooper JN, Anandalwar S, et al. Delaying appendectomy does not lead to higher rates of surgical site infections: a multi-institutional analysis of children with appendicitis. Ann Surg. 2015 Dec 16. [Medline].

  60. [Guideline] Korndorffer JR Jr, Fellinger E, Reed W. SAGES guideline for laparoscopic appendectomy. Surg Endosc. 2010 Apr. 24(4):757-61. [Medline]. [Full Text].

  61. Wilasrusmee C, Sukrat B, McEvoy M, Attia J, Thakkinstian A. Systematic review and meta-analysis of safety of laparoscopic versus open appendicectomy for suspected appendicitis in pregnancy. Br J Surg. 2012 Nov. 99(11):1470-8. [Medline].

  62. Liang MK, Lo HG, Marks JL. Stump appendicitis: a comprehensive review of literature. Am Surg. 2006 Feb. 72(2):162-6. [Medline].

  63. Barclay L. Ultrasound, CT Comparable to Detect Appendicitis in Children. Medscape Medical News. Available at http://www.medscape.com/viewarticle/817370. Accessed: December 9, 2013.

  64. Le J, Kurian J, Cohen HW, Weinberg G, Scheinfeld MH. Do clinical outcomes suffer during transition to an ultrasound-first paradigm for the evaluation of acute appendicitis in children?. AJR Am J Roentgenol. 2013 Dec. 201(6):1348-52. [Medline].

  65. Hurst AL, Olson D, Somme S, et al. Once-daily ceftriaxone plus metronidazole versus ertapenem and/or cefoxitin for pediatric appendicitis. J Pediatric Infect Dis Soc. 2015 Dec 24. [Medline].

 
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CT scan reveals an enlarged appendix with thickened walls, which do not fill with colonic contrast agent, lying adjacent to the right psoas muscle.
Sagittal graded compression transabdominal sonogram shows an acutely inflamed appendix. The tubular structure is noncompressible, lacks peristalsis, and measures greater than 6 mm in diameter. A thin rim of periappendiceal fluid is present.
Transverse graded compression transabdominal sonogram of an acutely inflamed appendix. Note the targetlike appearance due to thickened wall and surrounding loculated fluid collection.
Technetium-99m radionuclide scan of the abdomen shows focal uptake of labeled WBCs in the right lower quadrant consistent with acute appendicitis.
Perforated appendicitis.
Normal appendix; barium enema radiographic examination. A complete contrast-filled appendix is observed (arrows), which effectively excludes the diagnosis of appendicitis.
Table 1. MANTRELS Score
Characteristic Score
M = Migration of pain to the RLQ 1
A = Anorexia 1
N = Nausea and vomiting 1
T = Tenderness in RLQ 2
R = Rebound pain 1
E = Elevated temperature 1
L = Leukocytosis 2
S = Shift of WBCs to the left 1
Total 10
Source: Alvarado.[19]
RLQ = right lower quadrant; WBCs = white blood cells
Table 2. WBC Count and Likelihood of Appendicitis
WBC (× 10,000) Likelihood Ratio (95% CI)
4-7 0.10 (0-0.39)
7-9 0.52 (0-1.57)
9-11 0.29 (0-0.62)
11-13 2.8 (1.2-4.4)
13-15 1.7 (0-3.6)
15-17 2.8 (0-6.0)
17-19 3.5 (0-10)
19-22
Source: Dueholm et al.[24]
CI = confidence interval; WBC = white blood cell.
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