Diagnostic performance of [68Ga]Ga-DOTA-FAPI-04 for periprosthetic hip joint infection

Abstract Purpose To assess the efficiency of [68Ga]GaDOTAFAPI04 in diagnosing periprosthetic hip joint infection and establish a diagnostic standard of clinical significance based on uptake pattern. Methods [68Ga]GaDOTAFAPI04 PET/CT was performed in patients with symptomatic hip arthroplasty from December 2019 to July 2022. The reference standard was based on the 2018 Evidence-Based and Validation Criteria. Two diagnostic criteria, SUVmax and uptake pattern, were used to diagnose PJI. Meanwhile, original data were imported into IKT-snap to draw the view of interest, A.K. was used to extract features of clinical cases, and unsupervised clustering analysis was applied according to the groups. Results A total of 103 patients were included, 28 of whom had PJI. The area under the curve of SUVmax was 0.8969, which was better than that of all of the serological tests. The cutoff value of SUVmax was 7.530, and the sensitivity and specificity were 72% and 100%, respectively. The sensitivity, specificity and accuracy of the uptake pattern were 100%, 93.10% and 95%, respectively. In radiomics analysis, the features of PJI were significantly different from aseptic failure. Conclusion The efficiency of [68Ga]GaDOTAFAPI04 PET/CT in diagnosing PJI showed promising results, and the diagnostic criteria of the uptake pattern were more clinically instructive. Radiomics also showed a certain application prospect in the field of PJI. Trial registration number Trial registration: ChiCTR2000041204. Registered 24 September 2019.