Estimation of 99mTc-ciprofloxacin accumulation indexes in bone and joint bacterial infections.
OBJECTIVE
99mTc-ciprofloxacin is a radiopharmaceutical preparation sintetized to improve diagnostic accuracy of bacterial infections in human tissues. It is mostly applied in diagnosis of bone and joint infections. Many papers have confirmed its sensitivity to infection, but newer papers argued its specificity. The aim of this study was to compare the results of visual analysis of scintigrams to semiquantitative calculations of accumulation indexes with the assumption that calculation of indexes would improve the specificity for bone and joint infections.


METHODS
We examined 40 patients, 25 with confirmed bone and joint bacterial infections and 15 patients with bone and joint diseases without bacterial infection. Scintigraphy was performed 5 minutes, 1, 4 and 24 hours after intravenous (i.v.) injection of 99mTc-ciprofloxacin. Scintigrams were analysed visually and by calculation and comparation of accumulation indexes values.


RESULTS
Visual sensitivity was 94%, but specificity only 47%. Index calculation achieved much higher specificity (100% after 1, 4 and 24 hours for cut off value of 1.50). All basic index values (5 min) in the patients with infections increased in 24 hours. In 8 patients without infection occured a slight increase and in 7 patients decrease of basic index values.


CONCLUSIONS
Calculation of accumulation index values is needed in the use of 99mTc-ciprofloxacin scintigraphy as it is the only way to improve specificity for bacterial bone infections. Visual interpretation of results is sensitive, but not specific due to accumulation of the drug in a high percent of non infected bone and joint lesions.
Pucar
Dragan
D
Military Medical Academy, Institute for Nuclear Medicine, Belgrade, Serbia. pucardr@ptt.rs
Janković
Zoran
Z
Dugonjić
Sanja
S
Popović
Zoran
Z
D001170:Arthritis, Infectious / Q000000981:diagnostic imaging*; D001424:Bacterial Infections / Q000000981:diagnostic imaging*; D001850:Bone Diseases, Infectious / Q000000981:diagnostic imaging*; D001842:Bone and Bones / Q000000981:diagnostic imaging; D002939:Ciprofloxacin / Q000031:analogs & derivatives*; D006801:Humans; D007596:Joints / Q000000981:diagnostic imaging; D015609:Organotechnetium Compounds; D016459:Prosthesis-Related Infections / Q000000981:diagnostic imaging; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity
D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C431804:Technetium Tc 99m ciprofloxacin; D002939:Ciprofloxacin