Background: Abdominal pain is a common complaint in children and its differential diagnosis includes inflammatory bowel disease (IBD). The aim of the study was to assess the diagnostic accuracy of scintigraphy with 99mTechnetium Hexamethylpropyleneamine Oxime (99mTc-HMPAO) labeled leukocytes in children with suspected IBD.
Material and methods: Eighty-five children (age 12.4 ± 4.3 years, 47% boys) with suspected IBD based on clinical presentation, laboratory and ultrasound findings underwent scintigraphy with 99mTc-HMPAO labeled leukocytes. Abdominal scintigrams were acquired 40 min and 90 min post injection, and whole body scintigrams at 180 min. Scintigraphy was evaluated by two specialists in nuclear medicine. The results were compared with the final diagnosis established by endoscopy, histology, other imaging methods, and follow-up evaluated by an expert in pediatric gastroenterology.
Results: Scintigraphy results corresponded with the final diagnosis in 78 (91%) patients resulting in a sensitivity of 89% (95%CI 72 to 98%), specificity of 91% (95% CI 82 to 98%), and accuracy of 91% (95% CI 83 to 96%). The interobserver agreement was 0.82 (95% CI 0.75 to 0.88) and the radiation dose estimate was 4.2 ± 1.5 mSv. In 28 children (25 positives and 3 negatives on scintigraphy), the diagnosis of IBD was established by endoscopy, histology, MR enterography, or fluoroscopy. Five positive findings on scintigraphy were not confirmed by other methods or during follow-up.
Conclusion: Scintigraphy with 99mTc-HMPAO labeled leukocytes in children with suspected IBD has high accuracy and offers a non-invasive option for detecting the presence of gastrointestinal inflammation. Scintigraphy is a powerful non-invasive decision-making tool in the management of suspected IBD that may spare a greater proportion of children of more invasive and demanding examinations.
Keywords: 99mTc-HMPAO; inflammatory bowel disease; leukocyte; scintigraphy.