Appendicitis (peds)

This page is for pediatric patients. For adult patients, see: appendicitis


Drawing of colon with variability of appendix locations as seen from anterior view.
  • Most common between 9-12yr
  • Perforation rate 90% in children <4yr
  • NPV of 98% achieved if:
    • Lack of nausea (or emesis or anorexia)
    • Lack of maximal TTP in the RLQ
    • Lack of neutrophil count > 6750

Clinical Features

Location of McBurney's point (1), located two thirds the distance from the umbilicus (2) to the right anterior superior iliac spine (3).
  • Local tenderness + McBurney's point rigidity most reliable clinical sign


Infants (30 days - 2 yrs)

Preschool (2 - 5yrs)

School-age (6 - 12yrs)

Adolescents (>12yrs)

  • Present similar to adults
    • RLQ pain
    • Vomiting (occurs after onset of abdominal pain)
    • Anorexia

Differential Diagnosis

Pediatric Abdominal Pain

0–3 Months Old

3 mo–3 y old

3 y old–adolescence


Dilated, non-compressible appendix with appendicolith and surrounding free fluid[1]
Peri-appendiceal fat stranding in the setting of acute appendicitis.
Fecalith (arrow) and stranding in the setting of acute appendicitis.
Dialated appendix and stranding in the setting of acute appendicitis.

Pediatric Risk Scores

Pediatric Appendicitis Score

Nausea/vomiting +1
Anorexia +1
Migration of pain to RLQ +1
Fever +1
Cough/percussion/hopping tenderness +2
RLQ tenderness +2
Leucocytosis (WBC > 10,000) +1
Neutrophilia (ANC > 7,500) +1
  • Score ≤ 2
    • Low risk (0-2.5%)
    • Consider discharge home with close follow up
  • Score 3-6
    • Indeterminate risk
    • Consider serial exams, consultation, or imaging
  • Score ≥ 7
    • High risk
    • Consider surgical consultation

Pediatric Appendicitis Risk Calculator (pARC)

  • pARC score shown to outperform Pediatric Appendicitis Score. pARC score accurately assesses risk of appendicitis in children age 5 years and older in community EDs [2]

Alvarado Clinical Scoring System

Right Lower Quadrant Tenderness +2
Elevated Temperature (37.3°C or 99.1°F) +1
Rebound Tenderness +1
Migration of Pain to the Right Lower Quadrant +1
Anorexia +1
Nausea or Vomiting +1
Leukocytosis > 10,000 +2
Leukocyte Left Shift +1

Clinical scoring system, where a score (Total=10) is composed on presence/absence of 3 signs, 3 symptoms and 2 lab values to help guide in case management.

  • ≤3 = Appendicitis unlikely
  • ≥7 = Surgical consultation
  • 4-6 = Consider CT

MANTRELS Mnemonic: Migration to the right iliac fossa, Anorexia, Nausea/Vomiting, Tenderness in the right iliac fossa, Rebound pain, Elevated temperature (fever), Leukocytosis, and Shift of leukocytes to the left (factors listed in the same order as presented above).


Laboratory Findings

  • Abdominal panel
    • CBC
      • <10K is a negative predictor of appendicitis
      • However, normal WBC does not rule-out appendicitis
    • Chemistry
    • Consider LFTs + lipase
    • Consider coagulation studies (PT, PTT, INR), as a marker of liver function
  • Consider urine pregnancy test (age appropriate)
  • Urinalysis
  • Consider serum lactate


Consider in intermediate or higher risk patients

  • Ultrasound
    • Sn: 88%, Sp: 94%
    • Consider as 1st choice in non-obese children
    • Indeterminate ultrasound and an Alvarado <5 (see below) has an NPV of 99.6%[3]
  • CT with IV contrast
    • Sn: 94%, Sp: 95%
    • Consider if ultrasound is equivocal OR strong suspicion despite normal ultrasound


  • Patients can be ruled out via a combination of history, physical, labs, and imaging.
  • Confirmatory diagnosis is typically made on imaging
  • Ultrasound is typically performed first:
    • If appendix is positive, appendicitis is ruled in
    • If appendix is visualized and negative, appendicitis is ruled out
    • If appendix is unable to be visualized (i.e., indeterminant), then post-test probability is unchanged. Re-examine and consider CT as next diagnostic study.


Supportive Management



  • Surgical consult, NPO, surgical pre-op labs if appropriate


  • Admission

See Also


  2. Cotton D, et al., Validation of the Pediatric Appendicitis Risk Calculator (pARC) in a Community Emergency Department Setting. Annals Emrg. Med. 2019; 74(4) 471-480
  3. Blitman, et al. Value of focused appendicitis ultrasound and Alverado score in predicting appendicitis in children: Can we reduce the use of CT? AJR. 2015; 204:W707-W712.
  4. Yardeni D et al. Single daily dosing ceftriaxone and metronidazole vs standard triple antibiotic regimen for perforated appendicitis in children: a prospective randomized trial. J Pediatr Surg. 2008 Jun; 43(6): 981–985.