Population Covered By The Guidance
This pathway provides guidance on the imaging of adult patients with left iliac fossa pain, with emphasis on investigations for suspected diverticulitis and its complications.
Lead Researcher: Sian Chin
Experts & Contributors: Ravinder Dhillon, Richard Mendelson
Editorial Panel: Core membership
Link to Editorial Panel
Date reviewed: October 2018
Date Published: April 2019
- In suspected acute colonic diverticulitis, imaging is generally required to confirm the diagnosis and to evaluate for complications that may require surgical intervention. Contrast-enhanced CT is the imaging modality of choice
- CT can also demonstrate alternative diagnoses
- In young female patients, gynaecological causes are more common and should be investigated first with US
- Diverticular abscesses diagnosed on CT scan may be treated initially by CT guided percutaneous drainage or surgery
- Colon thickening on CT may represent inflammatory or neoplastic changes, so in some cases of diverticulitis, delayed colonoscopy (or CT colonography) may be warranted to rule out malignancy
References are graded from Level I to V according to the Oxford Centre for Evidence-Based Medicine, Levels of Evidence. Download the document
- Bhosale PR, Javitt MC, Atri M, Harris RD, Kang SK, Meyer BJ, et al. ACR Appropriateness criteria(R) acute pelvic pain in the reproductive age group. Ultrasound quarterly. 2016;32(2):108-15. (Guideline). View the reference
- Bhavsar AK, Gelner EJ, Shorma T. Common Questions About the Evaluation of Acute Pelvic Pain. Am Fam Physician. 2016;93(1):41-8. (Review article). View the reference
- Katz DS, Khalid M, Coronel EE, Mazzie JP. Computed tomography imaging of the acute pelvis in females. Can Assoc Radiol J. 2013;64(2):108-18. (Review article). View the reference
- Ackerman SJ, Irshad A, Anis M. Ultrasound for pelvic pain II: nongynecologic causes. Obstet Gynecol Clin North Am. 2011;38(1):69-83, viii. (Review article). View the reference
- Amirbekian S, Hooley RJ. Ultrasound evaluation of pelvic pain. Radiol Clin North Am. 2014;52(6):1215-35. (Review article). View the reference
- O'Malley ME, Wilson SR. Ultrasonography and computed tomography of appendicitis and diverticulitis. Semin Roentgenol. 2001;36(2):138-47. (Review article). View the reference
- American College of Radiology. ACR appropriateness criteria. Left lower quadrant pain - suspected diverticulitis. 2014. (Guideline). View the reference
- Sartelli M, Catena F, Ansaloni L, Coccolini F, Griffiths EA, Abu-Zidan FM, et al. WSES Guidelines for the management of acute left sided colonic diverticulitis in the emergency setting. World J Emerg Surg. 2016;11(1):37. (Guideline). View the reference
- Binda GA, Cuomo R, Laghi A, Nascimbeni R, Serventi A, Bellini D, et al. Practice parameters for the treatment of colonic diverticular disease: Italian Society of Colon and Rectal Surgery (SICCR) guidelines. Techniques in coloproctology. 2015;19(10):615-26. (Guidelines). View the reference
- Andeweg CS, Mulder IM, Felt-Bersma RJ, Verbon A, van der Wilt GJ, van Goor H, et al. Guidelines of diagnostics and treatment of acute left-sided colonic diverticulitis. Dig Surg. 2013;30(4-6):278-92.
- Siddiqui J, Zahid A, Hong J, Young CJ. Colorectal surgeon consensus with diverticulitis clinical practice guidelines. World Journal of Gastrointestinal Surgery. 2017;9(11):224-32. View the reference
- Vennix S, Morton DG, Hahnloser D, Lange JF, Bemelman WA. Systematic review of evidence and consensus on diverticulitis: an analysis of national and international guidelines. Colorectal Dis. 2014;16(11):866-78. View the reference
- Galetin T, Galetin A, Vestweber KH, Rink AD. Systematic review and comparison of national and international guidelines on diverticular disease. Int J Colorectal Dis. 2018;33(3):261-72.(Review article) View the reference
- Lameris W, van Randen A, van Gulik TM, Busch OR, Winkelhagen J, Bossuyt PM, et al. A clinical decision rule to establish the diagnosis of acute diverticulitis at the emergency department. Dis Colon Rectum. 2010;53(6):896-904. (Level II-III evidence). View the reference
- Toorenvliet BR, Bakker RF, Breslau PJ, Merkus JW, Hamming JF. Colonic diverticulitis: a prospective analysis of diagnostic accuracy and clinical decision-making. Colorectal Dis. 2010;12(3):179-86. (Level II-III evidence). View the reference
- Andeweg CS, Knobben L, Hendriks JC, Bleichrodt RP, van Goor H. How to diagnose acute left-sided colonic diverticulitis: proposal for a clinical scoring system. nn Surg. 2011;253(5):940-6. (Level II-III evidence). View the reference
- Andeweg CS, Wegdam JA, Groenewoud J, van der Wilt GJ, van Goor H, Bleichrodt RP. Toward an evidence-based step-up approach in diagnosing diverticulitis. Scand J Gastroenterol. 2014;49(7):775-84. (Level I evidence). View the reference
- Barat M, Dohan A, Pautrat K, Boudiaf M, Dautry R, Guerrache Y, et al. Acute colonic diverticulitis: an update on clinical classification and management with MDCT correlation. Abdominal radiology (New York). 2016;41(9):1842-50. (Review article). View the reference
- Shin S, Kim D, Kang UR, Yang C-S. Impact of CT imaging on predicting the surgical management of acute diverticulitis. Annals of Surgical Treatment and Research. 2018;94(6):322-9. (Level II-III evidence). View the reference
- Sharma PV, Eglinton T, Hider P, Frizelle F. Systematic review and meta-analysis of the role of routine colonic evaluation after radiologically confirmed acute diverticulitis. Ann Surg. 2014;259(2):263-72. (Level I evidence). View the reference
- Andrade P, Ribeiro A, Ramalho R, Lopes S, Macedo G. Routine colonoscopy after acute uncomplicated diverticulitis - challenging a putative indication. Dig Surg. 2017;34(3):197-202. (Level II-III evidence). View the reference
- Daniels L, Unlu C, de Wijkerslooth TR, Stockmann HB, Kuipers EJ, Boermeester MA, et al. Yield of colonoscopy after recent CT-proven uncomplicated acute diverticulitis: a comparative cohort study. Surg Endosc. 2015;29(9):2605-13. (Level III evidence). View the reference
- Campbell JP, Gunn AA. Plain abdominal radiographs and acute abdominal pain. Br J Surg. 1988;75(6):554-6. (Level III evidence). View the reference
- Li Y, Song J, Lin N, Zhao C. Computed tomography scan is superior to x-ray plain film in the diagnosis of gastrointestinal tract perforation. Am J Emerg Med. 2015;33(3):480.e3-5. (Review article). View the reference
- Min JH, Kim HC, Kim SW, Yang DM, Rhee SJ, Oh J, et al. The value of initial sonography compared to supplementary CT for diagnosing right-sided colonic diverticulitis. Japanese journal of radiology. 2017;35(7):358-65. (Level II-III evidence). View the reference
- Laméris W, van Randen A, van Es HW, van Heesewijk JPM, van Ramshorst B, Bouma WH, et al. Imaging strategies for detection of urgent conditions in patients with acute abdominal pain: diagnostic accuracy study. BMJ. 2009;338 (Level II-III evidence). View the reference
- Puylaert JB. Ultrasound of colon diverticulitis. Dig Dis. 2012;30(1):56-9. (Level III-IV evidence). View the reference
- Feingold D, Steele SR, Lee S, Kaiser A, Boushey R, Buie WD, et al. Practice parameters for the treatment of sigmoid diverticulitis. Dis Colon Rectum. 2014;57(3):284-94. (Guideline) View the reference
- Stollman N, Smalley W, Hirano I. American Gastroenterological Association institute guideline on the management of acute diverticulitis. Gastroenterology. 2015;149(7):1944-9. (Guideline) View the reference
- Chabok A, Pahlman L, Hjern F, Haapaniemi S, Smedh K. Randomized clinical trial of antibiotics in acute uncomplicated diverticulitis. Br J Surg. 2012;99(4):532-9. (Level II evidence) View the reference
- Shabanzadeh DM, Wille-Jorgensen P. Antibiotics for uncomplicated diverticulitis. Cochrane Database Syst Rev. 2012;11:Cd009092. (Level I evidence) View the reference
- Nally DM, Kavanagh DO. Current controversies in the management of diverticulitis: a review. Dig Surg. 2018. (Review article) View the reference
- Sharma PV, Eglinton T, Hider P, Frizelle F. Systematic review and meta-analysis of the role of routine colonic evaluation after radiologically confirmed acute diverticulitis. Ann Surg. 2014;259(2):263-72. (Level I evidence) View the reference
- Chabok A, Smedh K, Nilsson S, Stenson M, Pahlman L. CT-colonography in the follow-up of acute diverticulitis: patient acceptance and diagnostic accuracy. Scand J Gastroenterol. 2013;48(8):979-86. (Level II-III evidence) View the reference
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Pathway User Guide
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The relative radiation level (RRL) of each imaging investigation is displayed in the pop up box.
| SYMBOL | RRL | EFFECTIVE DOSE RANGE |
|---|---|---|
| None | 0 | |
| Minimal | < 1 millisieverts | |
| Low | 1-5 mSv | |
| Medium | 5-10 mSv | |
| 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 Left Iliac Fossa Pain/Pelvic Pain
Causes include
- Acute sigmoid diverticulitis
- Tubo-ovarian pathology and ectopic pregnancy in females
- Ischaemic colitis
- Pseudomembranous colitis
- Inflammatory bowel disease
- Locally perforated sigmoid carcinoma
- Renal colic
- Leaking abdominal aneurysm
Transabdominal/Transvaginal Ultrasound
Transabdominal/Transvaginal Ultrasound
Imaging modality of choice for evaluation of acute pelvic pain in young females
- Transabdominal US is the first imaging modality of choice for evaluation of acute pelvic pain in young females in the reproductive age group
- Provides information regarding the uterus, adnexa and ovaries as well as non-gynaecological causes of pain in young women with left lower quadrant/pelvic pain
- Transvaginal ultrasound where available and appropriate can provide more detailed examination for gynaecological disease
- Advantages
- Rapid
- Inexpensive
- No ionising radiation and requires no patient preparation or contrast material administration
- Limitations
- Interloop abscesses and abscesses filled with gas may not be well visualised or may mimic loops of bowel
- Limited value in diagnosing bowel-related pathology
- If there is suspicion of acute diverticulitis or diverticular abscess on US, CT may be indicated for further delineation
Suspected Crohn’s Disease
Computed Tomography (CT)
Computed Tomography
Generally the imaging modality of choice for the majority of patients with left iliac fossa pain of unknown aetiology. In suspected diverticulitis, CT is the best test to exclude a pericolic abscess or perforation
- Imaging modality of choice for evaluation of suspected acute diverticulitis
- Can also demonstrate alternative diagnoses, e.g. renal or vascular disease, epiploic appendagitis, etc.
- Clinical assessment alone is not precise enough to diagnose diverticulitis and imaging is generally recommended to confirm the diagnosis and to evaluate for complications
- Contrast-enhanced CT is the most accurate diagnostic test for diverticulitis, with 95% sensitivity and 96% specificity
- CT can be used to grade the severity of diverticulitis and is also a good predictor of the need for surgical management or percutaneous drainage of abscess
- However, a negative CT scan does not completely excluded diverticulitis
- In patients with suspected acute diverticulitis, an accurate diagnosis (including detection of alterative diagnoses) was made in 68% of patients with CT compared to 48% with ultrasound
- CT criteria of diverticulitis include
- Presence of diverticula with pericolic infiltration of fatty tissue
- Thickening of colonic wall
- Abscess formation
- Colonic cancer may uncommonly present as localised abscess and mimic diverticular disease on CT. There is ongoing discussion whether patients with uncomplicated diverticulitis should be routinely followed up with colonoscopy as a number of studies have demonstrated that the risk of cancer is low
- Advantages
- Unlimited field of view
- High clinical utility
- Short examination time
- Limitations
- Exposure to ionising radiation and contrast
Plain Radiography
Plain Radiography
An erect chest radiograph is a quick and widely available test that may demonstrate pneumoperitoneum, although it is less sensitive than CT
- An erect chest radiograph (CXR) is a quick and inexpensive investigation with low radiation that can demonstrate pneumoperitoneum, which may suggest complicated diverticulitis in the context of left iliac fossa pain
- Erect CXR is generally preferred to supine abdominal radiographs (AXR). A retrospective study of 250 surgically confirmed cases of hollow organ perforation found the sensitivity of erect CXR to be 85.1% compared to 80.4% for supine AXR and 98.0% for left decubitus AXR for the detection of pneumoperitoneum, though neither difference reached statistical significance. Lack of free air on plain radiography does not rule out perforation
- Lateral decubitus AXR should be considered to evaluate for perforation if erect CXR is not possible
- Alternatively, CT is more sensitive and is generally still indicated to evaluate the cause and location of the pathology, which may also be required for surgical planning
Ultrasound in Diverticulitis
Ultrasound in Diverticulitis
Alternative to CT in evaluating suspected acute diverticulitis that avoids ionising radiation
- There is evidence that suggests graded-compression ultrasound (US) has a comparable sensitivity to CT for diagnosing acute diverticulitis, although the specificity of US is slightly lower
- A meta-analysis found the sensitivity of US to be 90% vs 95% for CT (p=0.86), with specificity 90% vs 96% (0.04)
- Another study also supported the accuracy of US in the diagnosis of right-sided diverticulitis where complicated disease is less likely
- It has been suggested that a strategy where CT follows a preliminary negative or inconclusive US might reduce CT exams by 50%. This strategy is supported by a number of international guidelines
- However, other authors have suggested that patients who are critically ill with acute abdominal pain and signs of sepsis, possibly due to complicated diverticulitis, should proceed directly to CT without further delay
- Characteristic findings in acute diverticulitis include:
- Hypoechoic bowel wall thickening
- Presence of diverticula or abscesses
- Hyperechogenicity surrounding the bowel wall, implying active inflammation
- Advantages
- No exposure to ionising radiation or iodinated contrast
- Can be used to guide procedures e.g. percutaneous drainage of collection
- Disadvantages
- Skilled operator required
- Examination can be limited in obese patients
- Difficult to detect free air in deeply located abscesses
Management of Acute Diverticulitis
Conservative management is usually appropriate in uncomplicated diverticulitis. Percutaneous drainage or surgical intervention is indicated for larger abscesses
- The management of diverticulitis remains a challenge to the surgical community and there are still several areas of controversy
- Uncomplicated diverticulitis may be managed conservatively and many guidelines endorse outpatient treatment where possible, although clinicians are discordant on this practice
- Major guidelines continue to endorse the routine use of antibiotics in uncomplicated diverticulitis, , however randomised control trials have showed no benefit from antibiotics
- Small abscesses 13,18
- Larger abscesses require drainage and percutaneous drainage is favoured when feasible due to lower morbidity and mortality compared to emergency surgery ,
- Surgical intervention is indicated in purulent or fecal peritonitis (Hinchey III or IV); the recommendations for surgical approach vary ,
- Interval colonoscopy following acute diverticulitis is widely recommended. However this practice has been questioned with observational studies reporting the rates of colorectal cancer in following uncomplicated diverticulitis to be similar to routinely screened populations. There is still an increased risk following complicated diverticulitis. Given the associated risks and cost of colonoscopy, follow-up colonoscopy may only be warranted following complicated diverticulitis
- CT colonography may be an option if colonoscopy is incomplete or unfeasible, however it is not generally recommended for colonic surveillance and colorectal cancer screening
