Skip to main content
Log in

Utility of CT after sonography for suspected appendicitis in children: integration of a clinical scoring system with a staged imaging protocol

  • Original Article
  • Published:
Emergency Radiology Aims and scope Submit manuscript

Abstract

To improve diagnosis of pediatric appendicitis, many institutions have implemented a staged imaging protocol utilizing ultrasonography (US) first and then computed tomography (CT). A substantial number of children with suspected appendicitis undergo CT after US, and the efficient and accurate diagnosis of pediatric appendicitis continues to be challenging. The objective of the study is to characterize the utility of CT following US for diagnosis of pediatric appendicitis, in conjunction with a clinical appendicitis score (AS). Imaging studies of children with suspected appendicitis who underwent CT after US in an imaging protocol were retrospectively reviewed by three radiologists in consensus. Chart review derived the AS (range 0–10) and obtained the patient diagnosis and disposition, and an AS was applied to each patient. Clinical and radiologic data were analyzed to assess the yield of CT after US. Studies of 211 children (mean age 11.3 years) were included. The positive threshold for AS was determined to be 6 out of 10. When AS and US were concordant (N = 140), the sensitivity and specificity of US were similar to CT. When AS and US were discordant (N = 71) and also when AS ≥ 6 (N = 84), subsequent CT showed superior sensitivity and specificity to US alone. In the subset where US showed neither the appendix nor inflammatory change in the right lower quadrant (126/211, 60 % of scans), when AS < 6 (N = 83), the negative predictive value (NPV) of US was 0.98. However, when AS ≥ 6 (N = 43), NPV of US was 0.58, and the positive predictive value of subsequent CT was 1. There was a significant decrease in depiction of the appendix on US with patient weight-to-age ratio of >6 (kg/year, P < 0.001) and after-hours (1700 –0730 hours) performance of US (P < 0.001). Results suggest that the appendicitis score has utility in guiding an imaging protocol and support the contention that non-visualization of the appendix on US is not intrinsically non-diagnostic. There was little benefit to additional CT when AS < 6 and US did not show the appendix or evidence of inflammation; this would have avoided CT in 140/211 (66 %) patients. CT demonstrated benefit when AS ≥ 6, suggesting that cases with AS ≥ 6 and features that limit depiction of the appendix on US may be triaged to CT.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7

Similar content being viewed by others

References

  1. Lund DP (2008) Appendicitis. In: Kleinman R, Goulet O, Mieli-Vergani G, Sanderson I, Sherman P, Shneider B (eds) Walker’s pediatric gastrointestinal disease, 5th edn. BC Decker, Hamilton, p 353

    Google Scholar 

  2. Taylor GA (2004) Suspected appendicitis is children: in search of the single best diagnostic test. Radiology 231:293–295

    Article  PubMed  Google Scholar 

  3. Strouse PJ (2010) Pediatric appendicitis: an argument for US. Radiology 255:8–13

    Article  PubMed  Google Scholar 

  4. Kwok MY, Kim MK, Gorelick MH (2004) Evidenced-based approach to the diagnosis of appendicitis in children. Pediatr Emerg Care 20:690–698

    Article  PubMed  Google Scholar 

  5. Brennan GDG (2006) Pediatric appendicitis: pathophysiology and appropriate use of diagnostic imaging. Can J Emerg Med 8:425–432

    Google Scholar 

  6. Rosendahl K, Aukland SM, Fosse K (2004) Imaging strategies in children with suspected appendicitis. Eur Radiol 14(Suppl 4):L138–L145

    Article  PubMed  Google Scholar 

  7. Flum DR, Koepsell T (2002) The clinical and economic correlates of misdiagnosed appendicitis: nationwide analysis. Arch Surg 137:799–804

    Article  PubMed  Google Scholar 

  8. Margenthaler JA, Longo WE, Virgo KS et al (2003) Risk factors for adverse outcome after surgical treatment of appendicitis in adults. Ann Surg 238:59–66

    PubMed Central  PubMed  Google Scholar 

  9. van den Broek WT, van der Ende ED, Bijnen AB, Breslau PJ, Gouma DJ (2004) Which children could benefit from additional diagnostic tools in case of suspected appendicitis? J Pediatr Surg 39:570–574

    Article  PubMed  Google Scholar 

  10. Hagendorf BA, Clarke JR, Burd RS (2004) The optimal initial management of chlldren with suspected appendicitis: a decision analysis. J Pediatr Surg 39:880–885

    Article  PubMed  Google Scholar 

  11. Smink DS, Finkelstein JA, Garcia Peña BM, Shannon MW, Taylor GA, Fishman SJ (2004) Diagnosis of acute appendicitis in children using a clinical practice guideline. J Pediatr Surg 39:458–463

    Article  PubMed  Google Scholar 

  12. Garcia Peña BM, Taylor GA (2000) Radiologists’ confidence in interpretaton of sonography and CT in suspected pediatric appendicitis. AJR 175:71–74

    Article  Google Scholar 

  13. Alvarado A (1986) A practical score for the early diagnosis of acute appendicitis. Ann Emerg Med 15:557–564

    Article  CAS  PubMed  Google Scholar 

  14. Kharbanda AB, Taylor GA, Fishman SJ, Bachur RG (2005) A clinical decision rule to identify children at low risk for appendicitis. Pediatrics 116:709–716

    Article  PubMed  Google Scholar 

  15. Samuel M (2002) Pediatric appendicitis score. J Pediatr Surg 37:877–881

    Article  PubMed  Google Scholar 

  16. Goldman RD, Carter S, Stephens D, Antoon R, Mounstephen W, Langer JC (2008) Prospective validation of the pediatric appendicitis score. J Pediatr 153:278–282

    Article  PubMed  Google Scholar 

  17. Bhatt M, Joseph L, Ducharme FM, Dougherty G, McGillivray D (2009) Prospective validation of the pediatric appendicitis score in a Canadian pediatric emergency department. Acad Emerg Med 16:591–596

    Article  PubMed  Google Scholar 

  18. Doria AS (2009) Optimizing the role of imaging in appendicitis. Pediatr Radiol 39(Suppl 2):S144–S148

    Article  PubMed  Google Scholar 

  19. Rubin SZ, Martin DJ (1990) Ultrasonography in the management of possible appendicitis in childhood. J Pediatr Surg 25:737–740

    Article  CAS  PubMed  Google Scholar 

  20. Larson DB, Johnson LW, Schnell BM, Goske MJ, Salisbury SR, Forman HP (2011) Rising use of CT in child visits to the emergency department in the United States, 1995–2008. Radiology 259:793–801

    Article  PubMed  Google Scholar 

  21. Martin AE, Vollman D, Adler B, Caniano DA (2004) CT scans may not reduce the negative appendectomy rate in children. J Pediatr Surg 39:886–890

    Article  PubMed  Google Scholar 

  22. Wong KK, Cheung W, Tam PK (2008) Diagnosing acute appendicitis: are we overusing radiologic investigations? J Pediatr Surg 43:2239–2241

    Article  PubMed  Google Scholar 

  23. Bachur RG, Hennelly K, Callahan MJ, Monuteaux MC (2012) Advanced radiologic imaging for pediatric appendicitis, 2005–2009: trends and outcomes. J Pediatr 160:1034–1038

    Article  PubMed  Google Scholar 

  24. Miglioretti DL, Johnson E, Williams A et al (2013) The use of computed tomography in pediatrics and the associated radiation exposure and estimated cancer risk. JAMA Pediatr 167:700–707

    Article  PubMed Central  PubMed  Google Scholar 

  25. Partrick DA, Janik JE, Janik JS, Bensard DD, Karrer FM (2003) Increased CT scan utilization does not improve the diagnostic accuracy of appendicitis in children. J Pediatr Surg 38:659–662

    Article  PubMed  Google Scholar 

  26. Doria AS, Moineddin R, Kellenberger CJ et al (2006) US or CT for diagnosis of appendicitis in children and adults? A meta-analysis. Radiology 241:93–94

    Article  Google Scholar 

  27. Brenner D, Elliston C, Hall E, Berdon W (2001) Estimated risks of radiation-induced fatal cancer from pediatric CT. AJR 176:289–296

    Article  CAS  PubMed  Google Scholar 

  28. Brenner DJ, Hall EJ (2007) Computed tomography-an increasing source of radiation exposure. NEJM 357:2277–2284

    Article  CAS  PubMed  Google Scholar 

  29. Mathews JD, Forsythe AV, Brady Z et al (2013) Cancer risk in 680,000 people exposed to computed tomography scans in childhood or adolescence: data linkage study of 11 million Australians. BMJ 346:f2360

    Article  PubMed Central  PubMed  Google Scholar 

  30. Wan MJ, Krahn M, Ungar WJ et al (2009) Acute appendiciits in young children: cost-effectiveness of US versus CT in diagnosis—a Markov decision analytic model. Radiology 250:378–386

    Article  PubMed  Google Scholar 

  31. Safran DB, Pilati D, Folz E, Oller D (2001) Is appendiceal CT scan overused for evaluating patients with right lower quadrant pain? Am J Emerg Med 19:199–203

    Article  CAS  PubMed  Google Scholar 

  32. York D, Smith A, Phillips JD, von Allmen D (2005) The influence of advanced radiographic imaging on the treatment of pediatric appendicitis. J Pediatr Surg 40:1908–1911

    Article  PubMed  Google Scholar 

  33. Karakas SP, Guelfguat M, Leonidas JC, Springer S, Singh SP (2000) Acute appendicitis in children: comparison of clinical diagnosis with ultrasound and CT imaging. Pediatr Radiol 30:94–98

    Article  CAS  PubMed  Google Scholar 

  34. Garcia Peña BM, Mandl KD, Kraus SJ et al (1999) Ultrasonography and limited computed tomography in the diagnosis and management of appendicitis in children. JAMA 282:1041–1046

    Article  PubMed  Google Scholar 

  35. Ramarajan N, Krishnamoorthy R, Barth R et al (2009) An interdisciplinary initiative to reduce radiation exposure: evaluation of appendicitis in a pediatric emergency department with clinical assessment supported by a staged ultrasound and computed tomography pathway. Acad Emerg Med 16:1258–1265

    Article  PubMed  Google Scholar 

  36. Adibe OO, Amin SR, Hansen EN et al (2011) An evidence-based clinical protocol for diagnosis of acute appendicitis decreased the use of computed tomography in children. J Pediatr Surg 46:192–196

    Article  PubMed  Google Scholar 

  37. Warner BW, Kulick RM, Stoops MM, Mehta S, Stephan M, Kotagal UR (1998) An evidenced-based clinical pathway for acute appendicitis decreases hospital duration and cost. J Pediatr Surg 33:1371–1375

    Article  CAS  PubMed  Google Scholar 

  38. Garcia Peña BM, Taylor GA, Fishman SJ, Mandl KD (2002) Effect of an imaging protocol on clinical outcomes among pediatric patients with appendicitis. Pediatrics 110:1088–1093

    Article  Google Scholar 

  39. Krishnamoorthi R, Ramarajan N, Wang NE et al (2011) Effectiveness of a staged US and CT protocol for the diagnosis of pediatric appendicitis: reducing radiation exposure in the age of ALARA. Radiology 259:231–239

    Article  PubMed  Google Scholar 

  40. Hennelly KE, Bachur R (2011) Appendicitis update. Curr Opin Pediatr 23:281–285

    Article  PubMed  Google Scholar 

  41. Hernandez JA, Swischuk LE, Angel CA, Chung D, Chandler R, Lee S (2005) Imaging of acute appendicitis: US as the primary imaging modality. Pediatr Radiol 35:392–395

    Article  PubMed  Google Scholar 

  42. Gaitini D (2011) Imaging acute appendicitis: state of the art. J Clin Imaging Sci 1:1–9

    Article  Google Scholar 

  43. Kaiser S, Freckner B, Jorulf HK (2002) Suspected appendicitis in children: US and CT-a prospective randomized study. Radiology 223:633–638

    Article  PubMed  Google Scholar 

  44. van Breda Vriesman AC, Kole BJ, Puylaert JBCM (2003) Effect of ultrasonography and optional computed tomography on the outcome of appendectomy. Eur Radiol 13:2278–2282

    Article  PubMed  Google Scholar 

  45. The American College of Radiology. ACR Appropriateness Criteria® right lower quadrant pain—suspected appendicitis. National Guideline Clearinghouse. Agency for Healthcare Research and Quality, US Dept. of Health and Human Services. http://www.guidelines.gov/content.aspx?id=23816. Accessed 24 January 2012

  46. Amercian College of Emergency Physicians. Clinical policy: critical issues in the evaluation and management of emergency department patients with suspected appendicitis. National Guideline Clearinghouse. Agency for Healthcare Research and Quality, US Dept. of Health and Human Services. http://www.guidelines.gov/content.aspx?id=15598. Accessed 24 January 2012

  47. Puylaert JBCM (1986) Acute appendicitis: US evaluation using graded compression. Radiology 158:355–360

    Article  CAS  PubMed  Google Scholar 

  48. Jeffrey RB, Laing FC, Townsend RR (1988) Acute appendicitis: sonographic criteria based on 250 cases. Radiology 167:327–329

    Article  PubMed  Google Scholar 

  49. Gaitini D, Beck-Razi N, Mor-Yosef D et al (2008) Diagnosing acute appendicitis in adults: accuracy of color doppler sonography and MDCT compared with surgery and clinical follow-up. AJR 190:1300–1305

    Article  PubMed  Google Scholar 

  50. Lim HK, Lee WJ, Kim TH, Namgung S, Lee SJ, Lim JH (1996) Appendicitis: usefulness of color Doppler US. Radiology 201:221–225

    Article  CAS  PubMed  Google Scholar 

  51. Rodriguez DP, Vargas S, Callahan MJ, Zurakowski D, Taylor GA (2006) Appendicitis in young children: imaging experience and clinical outcomes. AJR 186:1158–1164

    Article  PubMed  Google Scholar 

  52. Curtin KR, Fitzgerald SW, Nemcek AA Jr, Hoff FL, Vogelzang RL (1995) CT diagnosis of acute appendicitis: imaging findings. AJR 164:905–909

    Article  CAS  PubMed  Google Scholar 

  53. Lund DP (2008) Appendicitis. In: Kleinman R, Goulet O, Mieli-Vergani G, Sanderson I, Sherman P, Shneider B (eds) Walker’s pediatric gastrointestinal disease, 5th edn. BC Decker, Hamilton, p 357

    Google Scholar 

  54. Schneider C, Kharbanda A, Bachur R (2007) Evaluating appendicitis scoring systems using a prospective pediatric cohort. Ann Emerg Med 49:778–784

    Article  PubMed  Google Scholar 

  55. Stephens PL, Mazzucco JJ (1999) Comparison of ultrasound and the Alvarado score for the diagnosis of acute appendicitis. Conn Med 63:137–140

    CAS  PubMed  Google Scholar 

  56. Galindo Gallego M, Fadrique B, Nieto MA et al (1998) Evaluation of ultrasonography and clinical diagnostic scoring in suspected appendicits. Br J Surg 85:37–40

    Article  CAS  PubMed  Google Scholar 

  57. Garcia Peña BM, Cook EF, Mandl KD (2004) Selective imaging strategies for the diagnosis of appendicitis is children. Pediatrics 113:24–28

    Article  PubMed  Google Scholar 

  58. Pacharn P, Ying J, Linam LE, Brody AS, Babcock DS (2010) Sonography in the evaluation of acute appendicitis: are negative sonographic findings good enough? J Ultrasound Med 29:1749–1755

    PubMed  Google Scholar 

  59. Schuh S, Man C, Cheng A et al (2011) Predictors of non-diagnostic ultrasound scanning in children with suspected acute appendicits. J Pediatr 158:112–118

    Article  PubMed  Google Scholar 

  60. Doria AS, Amernic H, Dick P et al (2005) Cost-effectiveness analysis of weekday and weeknight or weekend shiffts for assessment of appendicitis. Pediatr Radiol 35:1186–1195

    Article  PubMed  Google Scholar 

  61. Butler M, Servaes S, Srinivasan A, Edgar JC, Del Pozo G, Darge K (2011) US depiction of the appendix: role of abdominal wall thickness and appendiceal location. Emerg Radiol 18:525–531

    Article  PubMed  Google Scholar 

  62. Acheson J, Banerjee J (2011) Management of suspected appendicitis in children. Arch Dis Child Educ Pract Ed 95:9–13

    Article  Google Scholar 

  63. Douglas CD, Macpherson NE, Davidson PM, Gani JS (2000) Randomised controlled trial of ultrasonography in diagnosis of acute appendicitis, incorporating the Alvarado score. BMJ 321:1–7

    Article  Google Scholar 

  64. Tzanakis NE, Efstathiou SP, Danulidis K et al (2005) A new approach to accurate diagnosis of acute appendicitis. World J Surg 29:1151–1157

    Article  PubMed  Google Scholar 

  65. Kwan KY, Nager AL (2010) Diagnosing pediatric appendicitis: usefulness of laboratory markers. Am J Emerg Med 28:1009–1015

    Article  PubMed  Google Scholar 

  66. Kim HC, Yang DM, Lee CM et al (2011) Acute appendicitis: relationships between CT-determined severities and serum white blood cell counts and C-reactive protein levels. Br J Radiol 84:1115–1120

    Article  CAS  PubMed Central  PubMed  Google Scholar 

  67. Pruekprasert P, Maipang T, Geater A, Apakupakul N, Ksuntigij P (2004) Accuracy in diagnosis of acute appendicitis by computing serum C-reactive protein measurements, Alvarado score, and clinical impression of surgeons. J Med Assoc Thail 87:296–303

    Google Scholar 

  68. Wu HP, Chen CY, Kuo IT, Wu YK, Fu YC (2012) Diagnostic values of a single serum biomarker at different tiime points compared with Alvarado score and imaging examinations in pediatric appendicitis. J Surg Res 174:272–277

    Article  CAS  PubMed  Google Scholar 

  69. Rice HE, Arbesman M, Martin DJ et al (1999) Does early ultrasonography affect management of pediatric appendicitis? A prospective analysis. J Pediatr Surg 34:754–759

    Article  CAS  PubMed  Google Scholar 

  70. Frush DP, Frush KS, Oldham KT (2009) Imaging of acute appendicitis in children: EU versus U.S....or US versus CT? A North American perspective. Pediatr Radiol 39:500–505

    Article  PubMed  Google Scholar 

  71. Jahn H, Mathiesen FK, Neckelmann K, Hovendal CP, Bellstrøm T, Gottrup F (1997) Comparison of clinical judgment and diagnostic ultrasonography in the diagnosis of acute appendicitis: experience with a score-aided diagnosis. Eur J Surg 163:433–443

    CAS  PubMed  Google Scholar 

  72. Saidi RF, Ghasemi M (2000) Role of Alvarado score in diagnosis and treatment of suspected acute appendicitis. Am J Emerg Med 18:230–231

    Article  CAS  PubMed  Google Scholar 

  73. Neff LP, Ladd MR, Becher RD et al (2011) Computerized tomography utilization in children with appendicitis-differences in referring and children's hospitals. Am Surg 77:1061–1065

    PubMed  Google Scholar 

  74. Fryback DG, Thronbury JR (1991) The efficacy of diagnostic imaging. Med Decis Making 11:88–94

    Article  CAS  PubMed  Google Scholar 

  75. Bankier AA, Levine D, Halpern EF, Kressel HY (2010) Consensus interpretation in imaging research: is there a better way? Radiology 257:14–17

    Article  PubMed  Google Scholar 

  76. Newman K, Ponsky T, Kittle K et al (2003) Appendicitis 2000: variability in practice, outcomes, and resource utilization at thirty pediatric hospitals. J Pediatr Surg 38:372–379

    Article  PubMed  Google Scholar 

Download references

Conflict of interest

The authors declare that they have no conflict of interest.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Abhay Srinivasan.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Srinivasan, A., Servaes, S., Peña, A. et al. Utility of CT after sonography for suspected appendicitis in children: integration of a clinical scoring system with a staged imaging protocol. Emerg Radiol 22, 31–42 (2015). https://doi.org/10.1007/s10140-014-1241-1

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10140-014-1241-1

Keywords

Navigation