Netta Marlyn Blitman MD, Presenter: Nothing to Disclose

Muhammad Anwar MBBS, Abstract Co-Author: Nothing to Disclose

Kerryanne Brady MD, Abstract Co-Author: Nothing to Disclose

Hnin Khine MD, Abstract Co-Author: Nothing to Disclose

Benjamin Taragin MD, Abstract Co-Author: Nothing to Disclose

To evaluate the effectiveness of focused appendicitis ultrasound (FAUS) combined with Alvarado score to accurately identify children with suspected appendicitis, thereby reducing unnecessary CT scans and associated radiation exposure.

We retrospectively evaluated the US, CT and clinical and laboratory findings of 522 consecutive children (age range 8 months -21 years, 237 F, 153 M) who underwent FAUS for abdominal pain at our Pediatric Emergency Department, Jan. 2008 to Oct. 2009. At our institution FAUS includes evaluation of the gallbladder, appendix, right ovary and four quadrants/pelvis for fluid. All children had surgery or clinical follow-up to exclude missed appendicitis. Sonograms were characterized as positive (n=105), negative (n=27), or inconclusive (appendix not visualized) (n=390). Alternative diagnosis (n=14), and alternative findings (n=41), were noted.The Alvarado score from 0 to 10 was determined. Alvarado score assigns points based on RLQ pain, rebound vomiting fever, leukocytosis, anorexia and pain migration. FAUS and Alvarado score results were compared to surgery and pathology reports.  

Both FAUS result and Alvarado score were highly associated with likelihood of having surgery for appendicitis (p=.0001). FAUS alone provided conclusive results (positive, negative or alternative diagnosis) in 146/522 (28%) of children. In children with inconclusive FAUS, there were 43/390 9(11%) eventually diagnosed with appendicitis by CT (n=26) or Alvarado score (n=17). In children with inconclusive FAUS and Alvarado score < 5, (n=241/522, 46.1%), only 1 patient had appendicitis. In this group, the negative predictive value (NPV) of inconclusive US and Alvarado score combined was 99.6%. In children with inconclusive FAUS and Alvarado score > 6, the NPV decreased to 53%.

FAUS alone provides a conclusive diagnosis for a sizable (28%) number of children with suspected appendicitis. Children with an inconclusive FAUS and a low Alvarado score are extremely unlikely to have appendicitis, with a NPV of 99.6%. Avoiding CT scans in these patients is safe and can substantially reduce radiation exposure.

Combing FAUS with Alvarado score can identify children who have or are at very low risk for appendicitis. This may substantially reduce unnecessary CT examinations, with resultant radiation reduction.

Blitman, N, Anwar, M, Brady, K, Khine, H, Taragin, B, Value of Focused Appendicitis Ultrasound and Alvarado Score in the Diagnosis of Appendicitis in Children: Can We Reduce the Use of CT Scans?.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11007837.html