Iliac Fossa Pain (Acute Right)

Population Covered By The Guidance

This pathway provides guidance for the imaging of adult patients with right iliac fossa pain or suspected acute appendicitis, as well as the many mimickers of appendicitis.

Lead Researcher: Gurjeet Dulku

Experts & Contributors: Richard Mendelson

Editorial Panel: Core Membership
Link to Editorial Panel

Date reviewed: May 2015

Date Published: May 2015

Image 1a (Ultrasound): Dilated, non-compressible appendix with an echogenic appendicolith.

Acute Appendicitis

Image 1b and 1c (Computed Tomography): Dilated appendix with appendicolith (arrow).

Acute Appendicitis

Image 1b and 1c (Computed Tomography): Dilated appendix with appendicolith (arrow).

Acute Appendicitis

Image 2 (H&E, x2.5): Histological section showing acute suppurative appendicitis. There is ulceration of the mucosa associated with haemorrhage and a dense transmural infiltrate of neutrophils and mononuclear inflammatory cells.

Acute Appendicitis

Image 3a (Ultrasound): Direct demonstration of ectopic foetus (between callipers).

Ectopic Pregnancy

Image 3b (Ultrasound): Empty endometrial cavity.

Ectopic Pregnancy

Image 4a and 4b (HE, x20). Resection of fallopian tube with an ectopic tubal pregnancy. The histological section shows ulceration of the tubal epithelium, haemorrhage and chorionic villi (arrows) which confirm the presence of products of conception.

Ectopic Pregnancy

Image 4a and 4b (HE, x20). Resection of fallopian tube with an ectopic tubal pregnancy. The histological section shows ulceration of the tubal epithelium, haemorrhage and chorionic villi (arrows) which confirm the presence of products of conception.

Ectopic Pregnancy

Image 5 (Computed Tomography with intravenous contrast): Thickened loops of small bowel with stranding of the mesentery.

Crohn's Disease

Image 6: Segmental small bowel resection showing deep linear/serpiginous mucosal ulceration (blue arrow) and a thickened bowel wall with stricture formation (green arrow).

Crohn's Disease

  • In suspected acute appendicitis, imaging can significantly reduce the negative appendicectomy rate but must not delay treatment
  • Both ultrasound and CT are accurate for the diagnosis of appendicitis
  • Ultrasound is generally preferable as the first investigation in young patients because
    • There is no ionizing radiation
    • It can detect gynaecological causes of acute pain in young female patients

Date of literature search: May 2015

The search methodology is available on request. Email

References are graded from Level I to V according to the Oxford Centre for Evidence-Based Medicine, Levels of Evidence. Download the document

  1. Puylaert JBCM. US evaluation using graded compression. Radiology. 1986;158:355-60. (Level II evidence). View the reference
  2. Puylaert JBCM, Rutgers PH, Lalissang RI, et al. A prospective study of ultrasonography in the diagnosis of appendicitis. N Engl J Med. 1987;317:666-9. (Level III evidence)
  3. Abu-Yousef MM, Bleicher JJ, Maher JW, et al. High-resolution sonography of acute appendicitis. AJR Am J Roentgenol. 1987;19:53-8. (Level III evidence)
  4. Franke C, Böhner H, Yang Q, Ohmann C, Röher H. Ultrasonography for diagnosis of acute appendicitis: results of a prospective multicenter trial. World J Surg. 1999;23:141-6. (Level IV evidence)
  5. Poortman P, Lohle PNM, Schoemaker CMC, et al. Comparison of CT and sonography in the diagnosis of acute appendicitis: a blinded prospective study. AJR Am J Roentgenol. 2003;181:1355-9. (Level II evidence). View the reference
  6. Lee JW. Sonography of acute appendicitis. Semin Ultrasound CT MR. 2003;24:83-90. (Review article)
  7. Borushok KF, Jeffrey RB, Laing FC, Townsend RR. Sonographic diagnosis of perforation in patients with acute appendicitis. AJR Am J Roentgenol. 1990;154:275-8. (Level III evidence)
  8. Birnbaum B, Wilson S. Appendicitis at the millenium. Radiology. 2000;215:337-48. (Review article)
  9. Malone AJ, Wolf CR, Malmed AS, Melliere BF. Diagnosis of acute appendicitis: value of unenhanced CT. Am J Radiol. 1993;160:763-6. (Level III evidence)
  10. Lane MJ, Katz DS, Ross BA, et al. Unenhanced helical CT scan for suspected acute appendicitis. Am J Radiol. 1997;168:405-9. (Level III evidence)
  11. Rao PM, Rhea JT, Novelline RA, et al. Helical CT technique for the diagnosis of acute appendicitis: prospective evaluation of a focused appendix CT examination. Radiology. 1997;202:139-44. (Level II evidence). View the reference
  12. Schuller JG, Shortsleeve MJ, Goldenson RS, et al. Is there a role for abdominal computed tomographic scans in appendicitis. Arch Surg. 1998;133:373. (Level III evidence)
  13. Lane MJ, Liu DM, Huynh MD, et al. Suspected acute appendicitis: nonenhanced helical CT in 300 consecutive patients. Radiology. 1999;213:341-6. (Level II evidence). View the reference
  14. Wijetunga R, Doust B, Bigg-Wither G. The CT diagnosis of acute appendicitis. Semin Ultrasound CT MR. 2003;24:101-6. (Review article)
  15. Fuchs JR, Schlamberg JS, Shortsleeve MJ, et al. Impact of abdominal CT imaging on the management of appendicitis: an update. J Surg Res. 2002;106:131-6. (Level III evidence)
  16. O'Malley ME, Wilson SR. Ultrasonography and computed tomography of appendicitis and diverticulitis. Semin Roentgenol. 2001;36(2):138-47. (Review article)
  17. Rosengren D, Brown AF, Chu K. Radiological imaging to improve the emergency department diagnosis of acute appendicitis. Emerg Med Australas. 2004;16:410-6. (Level III evidence)
  18. van Breda Vriesman AC, Kole BJ, Puylaert JB. Effect of ultrasonography and optional computed tomography on the outcome of appendicectomy. Eur Radiol. 2003;13:2278-82. (Level III evidence)
  19. Lahaye MJ, Lambregts DMJ, Mutsaers E, Essers BAB, Breukink S, Cappendijk VC, et al. Mandatory imaging cuts costs and reduces the rate of unnecessary surgeries in the diagnostic work-up of patients suspected of having appendicitis. Eur Radiol. 2015;25(5):1464-70. (Level III evidence). View the reference

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SYMBOL RRL EFFECTIVE DOSE RANGE
No radiation None 0
Minimal radiation Minimal < 1 millisieverts
Low radiation Low 1-5 mSv
Medium radiation Medium 5-10 mSv
High radiation High >10 mSv

Disclaimer

Status Of Recommendations Each pathway is designed to assist clinicians in situations when faced with a large array of possible diagnostic tests and examinations. However, it is recognised that diagnostic practice may differ from a particular pathway depending on local availability of equipment and expertise, as well as the experience of individual clinicians. Therefore each pathway is neither a rigid set of rules, nor a substitute for clinical assessment, and individual patient circumstances should always be considered.

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Acute abdomen