Abstract
To assess the additive value of magnetic resonance imaging (MRI) in the setting of an equivocal US (Eq-US) with or without an elevated absolute neutrophil count (ANC). Single-institution, retrospective review of children ages 5-18 years who presented to the ER with suspected appendicitis from 9/2015 to 8/2016. US, ANC, and MRI results were reviewed. Imaging was identified as positive/suspicious, normal, or equivocal and ANC <8000 mm3 was defined as normal. 738 patients with a median age of 11 years (iqr 8-14) met inclusion criteria. us was equivocal in 61.4%. among 304 (67.1%) patients with an eq-us and normal anc, only 5 (1.6%) had acute appendicitis. in contrast, 28 of 149 patients (18.8%) with eq-us and elevated anc had appendicitis. mri was performed in 125 patients with eq-us and was positive suspicious in 2.9% (2 69) with normal anc and 25.0% (14 56) with elevated anc. mri had 94.7% sensitivity and 100% specificity for acute appendicitis in patients with an eq-us. mri has high sensitivity and specificity for diagnosing acute appendicitis in children. patients with eq-us plus a normal anc have a very low likelihood of appendicitis and do not typically require further imaging. mri may have utility for children with eq-us and elevated anc. level iii. to assess the additive value of magnetic resonance imaging (mri) in the setting of an equivocal us (eq-us) with or without an elevated absolute neutrophil count (anc). single-institution, retrospective review of children ages 5-18 years who presented to the er with suspected appendicitis from 9 2015 to 8 2016. us, anc, and mri results were reviewed. imaging was identified as positive suspicious, normal, or equivocal and anc><8000 mm3 was defined as normal. 738 patients with a median age of 11 years (iqr 8-14) met inclusion criteria. us was equivocal in 61.4%. among 304 (67.1%) patients with an eq-us and normal anc, only 5 (1.6%) had acute appendicitis. in contrast, 28 of 149 patients (18.8%) with eq-us and elevated anc had appendicitis. mri was performed in 125 patients with eq-us and was positive suspicious in 2.9% (2 69) with normal anc and 25.0% (14 56) with elevated anc. mri had 94.7% sensitivity and 100% specificity for acute appendicitis in patients with an eq-us. mri has high sensitivity and specificity for diagnosing acute appendicitis in children. patients with eq-us plus a normal anc have a very low likelihood of appendicitis and do not typically require further imaging. mri may have utility for children with eq-us and elevated anc. level iii.>
