Background: Investigation of suspected infection in prosthetic joint replacements is a difficult orthopaedic problem with important therapeutic implications.
Methods: We retrospectively analysed the results of 38 patients referred with a clinical suspicion of bone or joint infections. Referrals were made for suspected infection of prosthetic hip joints (17), total knee replacements (13), total elbow replacements (4) and total shoulder replacements (4). Sulesomab imaging was done with 650 MBq of 99mTc Sulesomab. The scintigraphic diagnosis was compared with the final clinical diagnosis and information collected from routine blood tests (erythrocyte sedimentation rate, C-reactive protein and full blood count), plain radiographs, appropriate microbiology, culture and/or histology where available. The final diagnosis was determined by conclusive microbiology, culture and/or histology, intra-operative findings, aspiration, complementary investigations like computed tomography/magnetic resonance imaging and long-term clinical follow-up.
Results: The overall sensitivity was 90.90% and specificity 81.48%. The individual sensitivity and specificity of each category were compared. Knee prostheses showed better sensitivity and specificity compared to that for hip prostheses.
Conclusions: 99mTc Sulesomab seems to be useful in excluding infection rather than confirming it, with a high negative predictive value (95.65%).