Gallium-68 Citrate PET/CT for Diagnosis and Treatment Response Assessment of Infections-Prospective Study

This article aims to assess the presence of skeletal and soft tissue infections before or after treatment and to assess treatment response in Ga-68 citrate positron emission tomography/computed tomography (PET/CT) scan positive patients.

A prospective study was conducted for 43 patients. The eligibility criteria included those patients clinically suspected of infections who underwent a Ga-68 citrate PET/CT. Exclusion criteria were pregnancy and lactation. Patients with suspicion of infection or treatment failure underwent a Ga-68 citrate PET/CT between January 2020 and November 2021. Among these, eight patients underwent a follow-up scan posttreatment to assess their treatment response. The Institutional Review Board (IRB No.12511) approved the study.

Forty-three patients underwent a diagnostic Ga-68 citrate PET/CT scan. The scan interpretation was based on visual comparison of uptake of Ga-68 citrate in the region of interest, which was compared with the normal side/adjacent soft tissue/blood pool. The semiquantitative parameter maximum standardized uptake value was retrospectively analyzed as well. PET/CT findings were correlated with tissue diagnosis, clinical symptoms, biochemical parameters like C-reactive protein (CRP), erythrocyte sedimentation rate, and total leukocyte count, and other imaging modalities with a statistically significant association with CRP ( p  = 0.001). Tissue diagnosis was considered the gold standard and out of the 43 patients included in the study, 27 had a tissue diagnosis. Sensitivity, specificity, negative predictive value, positive predictive value, and accuracy were calculated at 100, 87.5, 100, 95, and 96.3%, respectively.

Ga-68 citrate is a promising tool to assess the presence of bone and soft tissue infections before or after treatment.