1. Paediatric Abdominal Radiograph Use, Constipation, and Significant Misdiagnoses Stephen B. Freedman, MDCM, MSc, Jennifer Thull-Freedman, MD, MSc, David Manson, MD, Margot Follett Rowe, RN MSd, Maggie Rumantir, MD, Mohamed Eltorki, MD, and Suzanne Schuh, MD The Journal of Paediatrics October 2013

2. NICE recommends that abdominal radiographs should not be used to diagnose idiopathic constipation as a thorough history and examination is usually adequate.

3. Outcome Measures Primary: To determine the proportion of children diagnosed with constipation who were misdiagnosed Secondary: To determine if there is an association between AXR and misdiagnosis To identify significant features in children with misdiagnosis

4. Study flow chart

5. Methods November 2008- October 2010 1 paediatric emergency department in Toronto Aged < 18y

6. Methods Children assigned a discharge code – consistent with constipation were eligible. Misdiagnosis was defined as an alternative diagnosis within 7 days. The principal investigator reviewed all the medical records of the potential misdiagnosis cases.

7. Misdiagnosis Criteria 1. Resulted in hospitalisation or OPT procedure 2. Required a surgical or radiological intervention 3. Likely related to the index visit 4. Not identified at the index visit

8. Data abstraction To minimise bias specific words were used for subjective data fields. When multiple documentation sources were identified that of the most senior physician was used. If there was no physician documentation available then nursing documentation was used.

9. 9 Data Abstraction PMHX None Chronic illness Chronic illness + abdominal disease PMHX None Chronic illness Chronic illness + abdominal disease AXR as per final radiology report Normal consistent AXR as per final radiology report Normal consistent Abdominal Tenderness Presence Absence Abdominal Tenderness Presence Absence Abdominal Pain Presence Absence Abdominal Pain Presence Absence Rectal examination consistent inconsistent Rectal examination consistent inconsistent Look Well Unwell unclear Look Well Unwell unclear

10. Leech Scores A paediatric radiologist (blinded) assigned Leech scored to all AXR’s performed in the misdiagnosis cases & a random sample of the remaining AXR. Leech scores – assign 0-5 based on the amount of faeces in each 3 segment of colon

11. Study Flow Chart

12. 12 Misdiagnoses Appendicitis n=7 Appendicitis n=7 Brain tumour bowel obstruction n=2 Intussusception n=2 Ovarian torsion Perianal abscess Rhabdom yosarcom a Pancreatitis Perforated hartman’s pouch ALL Ileal volvulus Cardiomyopath y

13. Bowel obstruction The imaging from the index visit was reported the next day 1. Several loops of dilated small bowel. Large amount of stool in rectum; ileus vs early small bowel obstruction 2. Feacal matter seen throughout most of the colon. No obstruction.

14. 14 Secondary Outcomes 20 Patient (Index Visit) 20 Patient (Index Visit) 75% AXR vs 46% 75% AXR vs 46% 15% Blood Tests vs 12% 15% Blood Tests vs 12% 5% USS vs 9% 5% USS vs 9% 70% Abdominal Pain vs 49% 70% Abdominal Pain vs 49% 60% Abdominal tenderness vs 32% 60% Abdominal tenderness vs 32% 45% Administered enema

15. Discussion Conclusions are limited by the small number of cases. Statistically significant difference in AXR use between the 2 groups. This may reflect more atypical presentations with more severe abdominal pain and tenderness. All children with abdominal pain who underwent AXR were not included.

16. Good Points 10% of charts were reviewed in a blinded fashion by an independent reviewer. 16

17. Bad points All children with abdominal pain who underwent AXR were not included. Retrospective study therefore unable to be certain that signs/symptoms not recorded were not present. 17

18. Discussion 1 in 200 children were assigned a ‘serious’ alternative diagnosis in 7 days. Other diagnoses made at revisit include: UTI n=13 pneumonia n=5 HSP n=2 Renal failure n=1 18

19. Discussion An additional study of 1000 ED patients with abdominal pain reported that AXR findings NEVER resulted in a change in the initial clinical impression. Performing an AXR can lead to search satisfying and confirmation bias. 19

20. Iowa Criteria < 3 stools/week Large stool palpable Passing of large stool obstructing the toilet Posturing reflective of with-holding Painful defection