Detection of soft-tissue infections and osteomyelitis using a technetium-99m-labeled anti-granulocyte monoclonal antibody fragment.
Imaging of osteomyelitis and soft-tissue infections can be problematic with currently available agents; bone scans are often false-positive. Indium-111-oxine and 99mTc-HMPAO white blood cell (WBC) scans require ex vivo handling of blood with potential exposure to infectious agents, and 99mTc-antigranulocyte (IgG1) antibodies need 24 hr for final diagnosis.


METHODS
We investigated the use of 99mTc-murine anti-granulocyte monoclonal Fab' fragment in 20 patients with suspected osteomyelitis of soft-tissue infections. All patients also had 99mTc bone scans and 111In-oxine or 99mTc-HMPAO white blood cell scans. The final diagnosis was confirmed by culture, biopsy, surgery, follow-up, x-rays, CT or MRI. In vitro studies performed on granulocytes demonstrated no effect on their function when the anti-granulocyte monoclonal antibody fragment was added.


RESULTS
Sensitivity, specificity and diagnostic accuracy to detect infection was 88%, 75% and 80%, respectively. All lesions could be detected as early as 1 hr after injection of the antibody fragment. In comparison, WBC scanning had values of 86%, 78% and 81%, respectively. Some lesions could only be detected 24 hr following the injection of labeled WBCs. LeukoScan had three false-positives and WBC scanning had two false-positives.


CONCLUSIONS
Immunoscintigraphy with 99mTc-NCA-90 Fab' fragments offers rapid localization of foci, rapid and simple use, a negligible HAMA response rate, no effect on granulocyte function and an accuracy comparable to WBC scanning.
Becker
W
W
Dept. of Nuclear Medicine, University of Erlangen-Nuremberg, Germany.
Bair
J
J
Behr
T
T
Repp
R
R
Streckenbach
H
H
Beck
H
H
Gramatzki
M
M
Winship
M J
MJ
Goldenberg
D M
DM
Wolf
F
F
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal; D002634:Chemotaxis, Leukocyte; D005260:Female; D006098:Granulocytes / Q000276:immunology* / Q000502:physiology; D006801:Humans; D007239:Infections / Q000097:blood / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D009580:Nitroblue Tetrazolium; D015609:Organotechnetium Compounds; D010019:Osteomyelitis / Q000097:blood / Q000000981:diagnostic imaging*; D010091:Oximes; D010587:Phagocytosis; D011877:Radionuclide Imaging; D019690:Technetium Tc 99m Exametazime; D013778:Tetrazolium Salts; D013844:Thiazoles
D000911:Antibodies, Monoclonal; D015609:Organotechnetium Compounds; D010091:Oximes; D013778:Tetrazolium Salts; D013844:Thiazoles; D009580:Nitroblue Tetrazolium; D019690:Technetium Tc 99m Exametazime; C022616:thiazolyl blue