ACEP ID:

Appendicitis

Critical Issues in the Evaluation and Management of Emergency Department Patients With Suspected Appendicitis (January 2010)

Scope of Application

This guideline is intended for physicians working in hospital-based emergency departments (EDs).

Inclusion Criteria

This guideline is intended for patients presenting to the ED with acute, nontraumatic abdominal pain and possible or suspected appendicitis.

Exclusion Criteria

This guideline is not intended to address the care of patients with trauma-related abdominal pain or patients who are pregnant.


Recommendations offered in this policy are not intended to represent the only diagnostic and management options that the emergency physician should consider. ACEP recognizes the importance of the individual physician’s judgment and patient preferences.

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Critical Questions

  • In emergency department patients with possible acute appendicitis, can a clinical prediction rule be used to identify patients for whom no advanced imaging is required?

    Recommendations
    Level A Recommendations

    None specified.

    Level B Recommendations

    In pediatric patients, clinical prediction rules can be used to risk stratify for possible acute appendicitis. However, do not use clinical prediction rules alone to identify patients who do not warrant advanced imaging for the diagnosis of appendicitis.

    Level C Recommendations

    In adult patients, due to insufficient data, do not use clinical prediction rules to identify patients for whom no advanced imaging is required.

    Level A Recommendations

    None specified.

    Level B Recommendations

    In pediatric patients, clinical prediction rules can be used to risk stratify for possible acute appendicitis. However, do not use clinical prediction rules alone to identify patients who do not warrant advanced imaging for the diagnosis of appendicitis.

    Level C Recommendations

    In adult patients, due to insufficient data, do not use clinical prediction rules to identify patients for whom no advanced imaging is required.

  • In emergency department patients with suspected acute appendicitis, is the diagnostic accuracy of ultrasound comparable to CT or MRI for the diagnosis of acute appendicitis?

    Recommendations
    Level A Recommendations
    None specified.
    Level B Recommendations

    In pediatric patients with suspected acute appendicitis, if readily available and reliable, use right lower quadrant (RLQ) ultrasound (US) to diagnose appendicitis.

    An unequivocally* positive RLQ US with complete visualization of a dilated appendix has comparable accuracy to a positive CT or MRI in pediatric patients.

    Level C Recommendations

    In adult patients with suspected acute appendicitis, an unequivocally* positive RLQ US has comparable accuracy to a positive CT or MRI for ruling in appendicitis.

    *A non-visualized or partially-visualized appendix should be considered equivocal. Reasonable options for pediatric patients with an equivocal ultrasound and residual suspicion for acute appendicitis include MRI, CT, surgical consult, and/or observation, depending on local resources and patient preferences with shared decision making.

    Level A Recommendations
    None specified.
    Level B Recommendations

    In pediatric patients with suspected acute appendicitis, if readily available and reliable, use right lower quadrant (RLQ) ultrasound (US) to diagnose appendicitis.

    An unequivocally* positive RLQ US with complete visualization of a dilated appendix has comparable accuracy to a positive CT or MRI in pediatric patients.

    Level C Recommendations

    In adult patients with suspected acute appendicitis, an unequivocally* positive RLQ US has comparable accuracy to a positive CT or MRI for ruling in appendicitis.

    *A non-visualized or partially-visualized appendix should be considered equivocal. Reasonable options for pediatric patients with an equivocal ultrasound and residual suspicion for acute appendicitis include MRI, CT, surgical consult, and/or observation, depending on local resources and patient preferences with shared decision making.

  • In emergency department patients who are undergoing CT of the abdomen and pelvis for suspected acute appendicitis, does the addition of contrast improve diagnostic accuracy?

    Recommendations
    Level A Recommendations

    None specified.

    Level B Recommendations

    In adult and pediatric ED patients undergoing CT for suspected acute appendicitis, use IV contrast when feasible. The addition of oral or rectal contrast does not improve diagnostic accuracy.

    Level C Recommendations

    In adult ED patients undergoing CT for suspected acute appendicitis, non-contrast CT scans may be used for the evaluation of acute appendicitis with minimal reduction in sensitivity.

    Level A Recommendations

    None specified.

    Level B Recommendations

    In adult and pediatric ED patients undergoing CT for suspected acute appendicitis, use IV contrast when feasible. The addition of oral or rectal contrast does not improve diagnostic accuracy.

    Level C Recommendations

    In adult ED patients undergoing CT for suspected acute appendicitis, non-contrast CT scans may be used for the evaluation of acute appendicitis with minimal reduction in sensitivity.

Download the Policy

PDF Icon Appendicitis2023.pdf February 2023

Findings and Strength of Recommendations

Clinical findings and strength of recommendations regarding patient management were made according to the following criteria:
Level A recommendations
Generally accepted principles for patient care that reflect a high degree of clinical certainty (eg, based on evidence from 1 or more Class of Evidence I or multiple Class of Evidence II studies).
Level B recommendations
Recommendations for patient care that may identify a particular strategy or range of strategies that reflect moderate clinical certainty (eg, based on evidence from 1 or more Class of Evidence II studies or strong consensus of Class of Evidence III studies).
Level C recommendations
Recommendations for patient care that are based on evidence from Class of Evidence III studies or, in the absence of adequate published literature, based on expert consensus. In instances in which consensus recommendations are made, “consensus” is placed in parentheses at the end of the recommendation.
There are certain circumstances in which the recommendations stemming from a body of evidence should not be rated as highly as the individual studies on which they are based. Factors such as heterogeneity of results, uncertainty about effect magnitude, and publication bias, among others, might lead to a downgrading of recommendations.
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