EVALUATION OF THE EFFICACY OF TC-99M-INFECTON, A NOVEL AGENT FOR DETECTING SITES OF INFECTION

Aims-To determine the sensitivity and specificity of Tc-99m-Infecton ( Infecton), a novel ciprofloxacin based imaging agent, in detecting sit es of infection.Methods-Ninety patients thought to be suffering from a variety of infections were administered 300-400 MBq of Infecton intra venously. Whole body images were taken one and four hours later, Appro priate specimens were taken for microbiological investigations. Statis tical analysis was performed using a computer statistical package. Res ults-Ninety eight Infecton images were produced. Forty one of these we re positive, including three false positives, where the patients had n on-infective conditions. Fifty seven negative images were obtained, of which 41 were true negatives and 16 were false negatives, having defi nite evidence of infection. Thus, Infecton imaging has a sensitivity o f 70.3% and a specificity of 93.1% for detecting infective foci. The p ositive and negative predictive values were 92.6% and 71.9%, respectiv ely. Conclusion-Infecton imaging is a new diagnostic tool that is spec ific for detecting sites of bacterial infection in the body. The high positive predictive value displayed by the technique is clinically imp ortant because a positive image strongly supports a diagnosis of bacte rial infection. A negative result does not rule out an infection, and may be a result of previous or current antibiotic treatment and/or inf ection with organisms that do not take up Infecton. Infecton imaging h as major advantages over well established imaging techniques, includin g radiolabelled leucocytes, and may prove to be a superior method for localising bacterial infections.