Detection of acute bacterial infection within soft tissue injuries using a 99mTc-labeled chemotactic peptide.
OBJECTIVE
Infection imaging with a 99mTc-labeled chemotactic peptide was evaluated in a rabbit model of Escherichia coli infections in burned tissue.


METHODS
The peptide was radiolabeled with 99mTc via the hydrazino nicotinamide derivative. Three groups of six animals were studied: (group A) unilateral infected burns; (group B) bilateral burns with unilateral infection; and (group C) uninfected burns. Twenty-four hours after injury, groups A and B were infected, and 8 hours later, all animals were injected with approximately 0.50 mCi of 99mTc-peptide.


RESULTS
In groups A and B, excellent images of the infections were obtained at 3 to 4 and 16 to 18 hours after injection of the peptide. At 3 to 4 hours after injection, the target-to-background ratios (T/B) were 3.12 +/- 0.28 for group A and 4.33 +/- 0.61 for group B (p = n.s.). At 16 to 18 hours, the T/B ratios increased significantly (p < 0.01): group A = 8.10 +/- 1.03 and B = 7.70 +/- 1.25. The T/B ratio for group C was only slightly greater than unity.


CONCLUSIONS
These results indicate that 99mTc-labeled chemotactic peptides are effective radiopharmaceuticals for the rapid detection of focal sites of infection within thermally injured tissues.
Fischman
A J
AJ
Department of Radiology, Massachusetts General Hospital, Boston 02114.
Babich
J W
JW
Barrow
S A
SA
Graham
W
W
Carter
E
E
Tompkins
R G
RG
Rubin
R H
RH
D000818:Animals; D002056:Burns / Q000000981:diagnostic imaging* / Q000382:microbiology; D002630:Chemotactic Factors; D004927:Escherichia coli Infections / Q000000981:diagnostic imaging*; D005490:Focal Infection / Q000000981:diagnostic imaging* / Q000382:microbiology; D008297:Male; D011817:Rabbits; D011877:Radionuclide Imaging; D017556:Technetium Compounds
D002630:Chemotactic Factors; D017556:Technetium Compounds