Acute Appendicitis in Pediatric Patients: An Evidence-Based Review

Table of Contents

 

The dangers associated with misdiagnosis, delay, and perforation make quick and accurate diagnosis of appendicitis essential. This issue provides guidance for the management of children with appendicitis, including recommendations for diagnostic studies, pain management, prophylactic antibiotics, and surgical consultation. You will learn:

Age-based historical and physical examination findings that can narrow the differential diagnosis, including common signs of appendicitis (eg, Rovsing sign, pain upon coughing or hopping, and right iliac fossa tenderness)

Clinical scoring systems that can help guide the workup of appendicitis in children, including the pediatric appendicitis risk calculator (pARC), the pediatric appendicitis score (PAS), and the Alvarado score

Why ultrasound is recommended as the initial imaging study for patients with suspected appendicitis, and which imaging studies can be used when the ultrasound is equivocal

Appropriate initial stabilization strategies for patients with acute appendicitis

Recommendations for pain management and prophylactic antibiotics

Which patients may be candidates for nonoperative management

1. Abstract
2. Case Presentations
3. Introduction
4. Critical Appraisal of the Literature
5. Epidemiology and Pathophysiology
   1. Epidemiology
   2. Pathophysiology
6. Differential Diagnosis
7. Prehospital Care
8. Emergency Department Evaluation
   1. Age-Specific Considerations
      1. Infants
      2. Prepubertal Children
      3. Postpubertal Children
   2. General Considerations
   3. Physical Examination
9. Diagnostic Studies
   1. Scoring Systems
   2. Laboratory Studies
      1. White Blood Cell Count
      2. C-Reactive Protein
      3. Urinalysis
   3. Imaging Studies
      1. Ultrasound
      2. Computed Tomography
      3. Magnetic Resonance Imaging
      4. Selection of Imaging Study
10. Treatment
11. Special Populations
    1. Appendicitis in Children Aged < 5 Years
    2. Appendicitis in Pregnant Patients
12. Controversies and Cutting Edge
    1. New Scoring Systems
    2. Nonoperative Management
13. Disposition
14. Summary
15. Time- and Cost-Effective Strategies
16. Risk Management Pitfalls in the Management of Appendicitis in Pediatric Patients
17. Case Conclusions
18. Clinical Pathway for the Diagnosis of Appendicitis in Pediatric Patients
19. Tables and Figures
    1. Table 1. Differential Diagnosis of Right Lower Quadrant Abdominal Pain
    2. Table 2. Pediatric Appendicitis Score (PAS)
    3. Table 3. Alvarado Scoring System
    4. Figure 1. Ultrasound Images of Acute Appendicitis in a Child
20. References

Abstract

Appendicitis is the most common condition in children requiring emergency abdominal surgery. Delayed or missed diagnosis in young children is common and is associated with increased rates of perforation. Although several scoring systems have been developed, there is still no consensus on clinical, laboratory, and imaging criteria for diagnosing appendicitis. This issue reviews key age-based historical and physical examination findings, as well as clinical scoring systems, that can help guide the workup of appendicitis in children. The existing literature is reviewed to provide guidance for the management of children with appendicitis, including recommendations for diagnostic studies, prophylactic antibiotics, pain medication, and surgical consultation.

Case Presentations

An 11-year-old previously healthy boy presents to the ED on a busy Saturday evening. He has acute abdominal pain that started 18 hours ago as diffuse periumbilical abdominal pain. Within the last 3 hours or so, the pain migrated to the right lower quadrant and worsened in severity. The child says the bumps on the car ride to the hospital were painful, and hopping up and down makes the pain worse. He says it seems to be a bit better when he lies still and does not move. Oral ibuprofen has not really helped the pain. The patient has not eaten a meal all day and has vomited 3 times today. On presentation, he has a temperature of 38.3°C (101°F). He is fully immunized and does not have any upper respiratory symptoms. He has never had similar pain in the past and has no history of previous abdominal surgeries. He has a normal genitourinary examination. He has obvious discomfort with palpation of his abdomen with maximum tenderness in the right lower quadrant. He exhibits guarding and rebound tenderness. His mother asks you whether this could be appendicitis, and whether he will need surgery. You begin to think… Is this appendicitis? What else could it be? How will you definitively determine the diagnosis? What laboratory evaluation and imaging tests should you order? It is now 2:00 AM. If the patient definitely has appendicitis, does he need an emergent appendectomy or can it wait?

Your next patient is a 16-year-old girl with abdominal pain who is brought into the ED by her mother. When the girl arrived to the ED, her vital signs were age-appropriate except for tachycardia, with a heart rate of 115 beats/min. Initially, she had some mild pain in her lower abdomen that gradually got worse. What is your differential diagnosis? What history, physical examination findings, or diagnostic evaluations should you obtain?

Your last patient of the evening is a 4-year-old boy with abdominal pain who is brought into the ED by his parents. The parents report that the boy was at his baseline state of health until 2 days ago when he became more fatigued and did not want to play as much. Today, he has had poor oral intake and spiked a fever to 38.6°C (101.5°F). The patient has been moaning and seems to grab at his abdomen in pain. Again, the diagnosis of appendicitis comes to mind. Is the rate of perforated appendicitis higher in this age group? How do you get an accurate history and perform a physical examination if the child will not talk to you and cowers behind his father when you approach him?

Introduction

Abdominal pain is a common chief complaint for pediatric patients presenting to an emergency department (ED) and, most of the time, the etiology is self-limited and nonemergent. Nonetheless, acute appendicitis must be considered in the differential diagnosis of abdominal pain in the pediatric population because missed acute appendicitis can lead to morbidity and mortality as well as medicolegal consequences.

In children, acute appendicitis is the most common condition requiring emergency surgery, with > 75,000 children diagnosed annually in the United States.¹ The potential for morbidity and mortality from perforation of the appendix necessitates prompt diagnosis.² Although a variety of clinical scoring systems have been developed, there is still no consensus on clinical, laboratory, and imaging criteria for diagnosing appendicitis, which poses a dilemma for the emergency clinician.^3-5

This issue of Pediatric Emergency Medicine Practice reviews the existing literature to help develop strategies for the diagnosis and management of appendicitis in the pediatric population.

Critical Appraisal of the Literature

A literature search was performed in PubMed using the search terms appendicitis, abdominal pain, pediatrics, clinical scoring systems, ultrasound, diagnostic tests, radiation risk, and non-operative management. An English language filter was applied, and articles were sorted by relevance. Several thousand articles were found, with over 1000 screened by title, then abstract. A total of 101 articles were chosen for inclusion.

There are many deficiencies inherent to the quality of the literature, including the lack of pediatric studies and more retrospective studies. According to standard evidence-level scales, the majority of evidence for pediatric appendicitis falls into the “weak” or “moderately strong” categories, and there are many single-center studies with limited enrollment. There is an article from the Effective Health Care Program on the “Diagnosis of Right Lower Quadrant Pain and Suspected Appendicitis” in the National Guidelines Clearinghouse.⁶ Despite these studies, there is no clear consensus on the approach to the pediatric patient with abdominal pain.

Risk Management Pitfalls in the Management of Appendicitis in Pediatric Patients

1. “I saw this patient in the ED 2 days ago. He presented with 2 hours of vague abdominal pain, and his exam was not consistent with acute appendicitis. I can't believe he is back today with a perforated appendix.”

Early appendicitis can present with vague abdominal pain with a broad differential diagnosis. Therefore, it can be easy to miss early appendicitis. If a patient presents to the ED with < 24 hours of abdominal pain or the diagnosis is equivocal, close follow-up with a primary care provider or ED follow-up should be ensured if the patient’s symptoms persist.

8. “This 3-year-old boy seemed to have abdominal pain on exam, but he had a normal appendix ultrasound. He re-presented to the ED 2 days later with a large right-sided basilar pneumonia.”

The preverbal child can be difficult to examine in the ED. Even though it is true that children aged < 5 years with appendicitis often present with a perforated appendix, other diagnoses are much more common in this age group and should be considered. Failing to consider a broad differential may result in missed pathology.

9. “I decided to withhold morphine from my 8-year-old patient with suspected appendicitis. I didn’t want to miss a diagnosis because I administered an analgesic.”

Early analgesia is recommended. There is no increase in missed appendicitis or in negative appendectomies after analgesia. Adequate pain control for patients with suspected appendicitis in the ED is imperative.

Tables and Figures

References

Evidence-based medicine requires a critical appraisal of the literature based upon study methodology and number of subjects. Not all references are equally robust. The findings of a large, prospective, randomized, and blinded trial should carry more weight than a case report.

To help the reader judge the strength of each reference, pertinent information about the study is included in bold type following the reference, where available. In addition, the most informative references cited in this paper, as determined by the author, are highlighted.

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2. Pena BM, Taylor GA, Fishman SJ, et al. Costs and effectiveness of ultrasonography and limited computed tomography for diagnosing appendicitis in children. Pediatrics. 2000;106(4):672-676. (Prospective; 139 patients)
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40. Gronroos JM, Gronroos P. Leucocyte count and C-reactive protein in the diagnosis of acute appendicitis. Br J Surg. 1999;86(4):501-504. (Retrospective; 300 patients)
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70. Bachur RG, Dayan PS, Bajaj L, et al. The effect of abdominal pain duration on the accuracy of diagnostic imaging for pediatric appendicitis. Ann Emerg Med. 2012;60(5):582-590. (Prospective; 1810 patients)
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79. Kharbanda AB, Christensen EW, Dudley NC, et al. Economic analysis of diagnostic imaging in pediatric patients with suspected appendicitis. Acad Emerg Med. 2018;25(7):785-794. (Prospective; 2300 patients)
80. Fullerton K, Depinet H, Iyer S, et al. Association of hospital resources and imaging choice for appendicitis in pediatric emergency departments. Acad Emerg Med. 2017;24(4):400-409. (Retrospective; 1090 patients)
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87. Cameron DB, Williams R, Geng Y, et al. Time to appendectomy for acute appendicitis: a systematic review. J Pediatr Surg. 2018;53(3):396-405. (Review)
88. Stevenson MD, Dayan PS, Dudley NC, et al. Time from emergency department evaluation to operation and appendiceal perforation. Pediatrics. 2017;139(6). (Prospective; 955 patients)
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90. Mourad J, Elliott JP, Erickson L, et al. Appendicitis in pregnancy: new information that contradicts long-held clinical beliefs. Am J Obstet Gynecol. 2000;182(5):1027-1029. (Retrospective; 66,993 deliveries)
91. Richards C, Daya S. Diagnosis of acute appendicitis in pregnancy. Can J Surg. 1989;32(5):358-360. (Case control; 28 patients)
92. Barloon TJ, Brown BP, Abu-Yousef MM, et al. Sonography of acute appendicitis in pregnancy. Abdom Imaging. 1995;20(2):149-151. (Case series; 22 sonograms)
93. Kanal E, Barkovich AJ, Bell C, et al. ACR guidance document for safe MR practices: 2007. AJR Am J Roentgenol. 2007;188(6):1447-1474. (Clinical guidelines)
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95. Bickell NA, Aufses AH Jr, Rojas M, et al. How time affects the risk of rupture in appendicitis. J Am Coll Surg. 2006;202(3):401-406. (Retrospective; 219 patients)
96. Yilmaz HG, Akgun Y, Bac B, et al. Acute appendicitis in pregnancy--risk factors associated with principal outcomes: a case control study. Int J Surg. 2007;5(3):192-197. (Case control; 52 patients)
97. McGory ML, Zingmond DS, Tillou A, et al. Negative appendectomy in pregnant women is associated with a substantial risk of fetal loss. J Am Coll Surg. 2007;205(4):534-540. (Retrospective; 94,789 patients)
98. Huang L, Yin Y, Yang L, et al. Comparison of antibiotic therapy and appendectomy for acute uncomplicated appendicitis in children: a meta-analysis. JAMA Pediatr. 2017;171(5):426-434. (Meta-analysis; 404 patients)
99. Georgiou R, Eaton S, Stanton MP, et al. Efficacy and safety of nonoperative treatment for acute appendicitis: a meta-analysis. Pediatrics. 2017;139(3):e20163003. (Meta-analysis; 413 patients)
100. Hall NJ, Eaton S, Abbo O, et al. Appendectomy versus non-operative treatment for acute uncomplicated appendicitis in children: study protocol for a multicentre, open-label, non-inferiority, randomised controlled trial. BMJ Paediatr Open. 2017;1(1):bmjpo-2017-000028. (Randomized controlled trial; 978 planned patients)
101. Wesson DE BM. Acute appendicitis in children: management. UpToDate. Accessed August 15, 2019. (Review)

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Points and Pearls Excerpt

• Studies in adults with appendicitis show that abdominal pain almost always precedes vomiting. This typical sequence is less common in preschool-aged children; they can present with vomiting that precedes abdominal pain.
• Fever is the most suggestive sign of appendicitis in patients with undifferentiated abdominal pain. Rovsing sign is the examination finding that is most suggestive of acute appendicitis. Other signs include cough/hop pain and right iliac fossa tenderness.
• Basilar pneumonia should be considered for all children presenting with abdominal pain.
• Consider ordering a pelvic ultrasound for girls of childbearing age, as pelvic pathology can be confused with appendicitis.

Most Important References

• Kharbanda AB, Vazquez-Benitez G, Ballard DW, et al. Development and validation of a novel pediatric appendicitis risk calculator (pARC). Pediatrics. 2018;141(4). (Prospective; 3849 patients)
• Schneider C, Kharbanda A, Bachur R. Evaluating appendicitis scoring systems using a prospective pediatric cohort. Ann Emerg Med. 2007;49(6):778-784. (Prospective; 588 patients)
• Ebell MH, Shinholser J. What are the most clinically useful cutoffs for the Alvarado and pediatric appendicitis scores? A systematic review. Ann Emerg Med. 2014;64(4):365-372.e362. (Review article)
• Schuh S, Man C, Cheng A, et al. Predictors of non-diagnostic ultrasound scanning in children with suspected appendicitis. J Pediatr. 2011;158(1):112-118. (Prospective; 263 patients)
• Partain KN, Patel A, Travers C, et al. Secondary signs may improve the diagnostic accuracy of equivocal ultrasounds for suspected appendicitis in children. J Pediatr Surg. 2016;51(10):1655-1660. (Retrospective; 825 patients)