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Paper of the week: Labeled white blood cell/bone marrow single-photon emission computed tomography with computed tomography fails in diagnosing chronic periprosthetic shoulder joint infection.

Paper of the week: Labeled white blood cell/bone marrow single-photon emission computed tomography with computed tomography fails in diagnosing chronic periprosthetic shoulder joint infection. Falstie-Jensen T, Daugaard H, Søballe K, Ovesen J, Arveschoug AK, Lange J; ROSA study group. J Shoulder Elbow Surg. 2019 Jan 31. pii: S1058-2746(18)30782-1. doi: 10.1016/j.jse.2018.10.024.

Summary by Dr. Sreeram Penna

This prospective cohort study assessed the diagnostic accuracy of combined labeled leukocyte (WBC) and technetium 99m sulfur colloid bone marrow imaging (WBC/BM) single-photon emission computed tomography-computed tomography in chronic shoulder prosthetic joint infection (PJI). Researchers reviewed patients with a failed shoulder arthroplasty, which was defined as any unsatisfactory result of any cause. Researchers considered shoulder infected if 3 positive tissue cultures with the same bacteria or if a sinus tract communicating to the prosthesis was present. The final cohort of 29 patients was included in the study. Of these 11 were considered positive based on infection definition criteria used. Only 2 patients in the infected group had positive WBC/BM single-photon emission computed tomography (2/11, 18.2%). There were no false positive cases in the study. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of detecting chronic shoulder PJI using this test was 0.18, 1.00, 1.00, 0.67, and 0.69 respectively. Although the study had a low sample size it has shown a lack of utility of bone scan in improving the diagnostic accuracy of chronic shoulder PJI.