Abnormal Bladder Mimicking Proctitis on Tc-99m HMPAO Leucocytes Imaging for Inflammatory Bowel Disease

• Published in: Clinical nuclear medicine 2008-11, Vol.33 (11), p.816-818
• Main Authors: Balan, Kottekkattu K, Selvan, Shilpa, Balan, Anupama, Seshadri, Nagabhushan
• Format: Article
• Language: English
• Subjects: Blood Transfusion, Autologous; Colon - surgery; Diagnosis, Differential; Female; Gardner Syndrome - surgery; Humans; Inflammatory Bowel Diseases - diagnostic imaging; Inflammatory Bowel Diseases - physiopathology; Leukocyte Count; Leukocyte Transfusion; Leukocytes - cytology; Leukocytes - diagnostic imaging; Middle Aged; Proctitis - diagnostic imaging; Radionuclide Imaging; Technetium Tc 99m Exametazime - pharmacokinetics; Tomography, X-Ray Computed; Urinary Bladder - abnormalities; Urinary Bladder - diagnostic imaging
• ISSN: 0363-9762; 1536-0229
• DOI: 10.1097/RLU.0b013e318187ef0a

Radio-labeled leukocyte imaging is a routine procedure for assessing the activity and distribution of inflammatory bowel disease (IBD). Because of the well known advantages of Tc-99m over In-111 such as low radiation, better imaging characteristics, localization of disease to specific bowel segments, especially identification of small bowel disease, easy availability, and cost-effectiveness, Tc-99m HMPAO-leukocyte scintigraphy is preferred in patients with suspected bowel inflammation. Bowel uptake of leukocytes, however, is nonspecific and may be positive in a wide variety of other conditions including infection, vasculitis, neoplasm, and graft versus host disease. Nonspecific bowel activity, not seen on In-111 leukocyte studies, may also give rise to a mistaken diagnosis of IBD. The normal distribution of Tc-99m labeled leukocytes gives rise to urinary and rarely gallbladder activity, both of which are the result of the excretion of secondary hydrophilic complexes of Tc-99m HMPAO. We report a case where abnormal bladder shape mimicked active proctitis on Tc-99m HMPAO leukocyte imaging for IBD.