A Prospective Comparison of^99mTc-Labeled Polyclonal Human Immunoglobulin and¹¹¹In Granulocytes for Localization of Inflammatory Bowel Disease

Abstract

There is a need for an easily prepared radiopharmaceutical agent for the detection of inflammation and infection. In a group of 14 patients with inflammatory bowel disease (IBD), the detection of actively involved intestinal segments by nonspecific human polyclonal immunoglobulin (IgG) labeled with 99mT~ was compared with that of "'In granulocytes. To determine the specificity of 9RT~-IgG scintigraphy, 8 control patients without clinical indications of intestinal inflammation were examined. gPmTc-IgG was found in the left colon in 8 and in the right colon in 7 of the 8 controls 4 hours after the injection. At that time of scintigraphy only 4 IBD patients exhibited a more intense accumulation at the site of the intestinal segments with active disease. In contrast, in a randomized comparison with "'In granulocytes scintigraphy was-positive in 1 1 patients with the latter technique. Moreover, fewer diseased segments were seen in the 4 patients with positive %"' Tc-IgG scintigraphy (6 versus 12 with "'In granulocytes). In view of the low sensitivity and specificity, it is concluded that 99"Tc-IgG is not suitable for the scintigraphic staging of IBD patients.

Radiopharmaceuticals for the Visualization of Infectious and Inflammatory Lesions

“…After 4 h activity may be seen in the gastrointestinal system due to dissociation of 99m Tc from particles and oxidation to free pertechnetate [121]. Accumulation of this radionanocolloid in various disease states have been demonstrated [121][122][123][124]129]. Accumulation of this radionanocolloid in various disease states have been demonstrated [121][122][123][124]129].…”

“…Typical nanoparticles include 99m Tc-albumin nanocolloid [27,[121][122][123][124][125] and liposomes [126,127]. Due to their small size nanoparticles remain in circulation and make contact with inflammatory/infected cells for relatively longer periods of time.…”

Use of 99mTc-mononuclear leukocyte scintigraphy in nosocomial fever

“…Scintigraphy using 111 In-granulocyte-oxine and 99m Tc-HMPAO-leukocyte is a well-established imaging technique for visualizing infection and chronic inflammatory bowel disease (1,3,4,12,14,(18)(19)(20). Used for suspected intra-abdominal abscess, osteomyelitis, vascular prosthesis infection, or chronic inflammatory bowel disease, 111 In-granulocyte and 99m Tc-HMPAO-leukocyte scintigraphs are highly sensitive and specific (1,3,4,12,14,(18)(19)(20). These techniques are often performed on patients with fevers of unknown origin, defined as patients with more than 3 weeks of illness and fever higher than 38.3˚C documented on several occasions, and no diagnostic clue despite 1 week of intensive inpatient investigation (14,16).…”