RAPID DETECTION OF HUMAN INFECTIONS WITH F-18 FLUORODEOXYGLUCOSE AND POSITRON-EMISSION-TOMOGRAPHY - PRELIMINARY-RESULTS

The purpose of this study was to evaluate the feasibility of 2-[fluori ne-18]fluoro-2-deoxy-D-glucose (FDG) and positron emission tomography (PET) for rapid detection of human infections. Eleven patients who wer e known or suspected to be harboring various infections were studied w ith FDG-PET. Dynamic scans over the putative infection sites were perf ormed immediately after FDG (370 MBq) injection through 60 min, and st atic images including multiple projection images were then obtained. F DG uptake was assessed visually into four grades (0, normal; 1, probab ly normal; 2, probably abnormal; 3, definitely abnormal). For the semi quantitative index of FDG uptake in infections, the standardized uptak e value of FDG normalized to the predicted lean body mass (SUV-lean, S UL) was determined from the images obtained at 50-60 min after FDG inj ection. PET results were compared with final clinical diagnoses. Eleve n lesions in eight patients, which were interpreted as grade 2 or 3 by FDG-PET, were all concordant with active infectious foci. The SUL val ues of infections ranged from 0.97 to 6.69. In two patients, FDG-PET c orrectly showed no active infection. In one patient, it was difficult to detect infectious foci by FDG-PET due to substantial normal backgro und uptake of FDG. In total, FDG-PET correctly diagnosed the presence or absence of active infection in 10 of 11 patients. Fusion images of PET with computed tomography showed the most intense FDG uptake to be within an abscess wall. In conclusion, FDG-PET appears to be a promisi ng modality for rapid imaging of active human infections. More extensi ve clinical evaluation is warranted to determine the accuracy of this method.