Is 99mTc-HMPAO-leukocyte imaging an accurate method in evaluating therapy result in prosthetic joint infection and diagnosing suspected chronic prosthetic joint infection?

• Published in: The quarterly journal of nuclear medicine and molecular imaging Vol. 64; no. 1; p. 85
• Main Authors: Teiler, Johan, Ahl, Marcus, Åkerlund, Börje, Wird, Sara, Brismar, Harald, Bjäreback, Annie, Hedlund, Håkan, Holstensson, Maria, Axelsson, Rimma
• Format: Journal Article
• Language: English
• Published: Italy 01.03.2020
• Subjects: Aged; Anti-Bacterial Agents - therapeutic use; Chronic Disease; Cohort Studies; Female; Humans; Image Processing, Computer-Assisted; Joint Diseases - diagnostic imaging; Joint Diseases - drug therapy; Leukocytes - cytology; Male; Prosthesis-Related Infections - diagnostic imaging; Prosthesis-Related Infections - drug therapy; Retrospective Studies; Technetium Tc 99m Exametazime; Treatment Outcome
• ISSN: 1827-1936
• DOI: 10.23736/S1824-4785.19.03040-1

To investigate the sensitivity and specificity of 99mTc-HMPAO-leukocyte imaging in evaluating therapy result in patients with prosthetic joint infection (PJI) and in diagnosing suspected chronic PJI. Sixty-two patients (63 joints) with microbiologically verified PJI were examined by leukocyte imaging to evaluate therapy result during or at the end of antibiotic treatment or if the patient had a chronic PJI after treatment. Group 1 consisted of 49 patients with on-going or within less than 14 days of ending antibiotic treatment examined to evaluate response. Group 2 consisted of 13 patients examined after completed treatment on suspicion of chronic PJI with no or recently initiated renewed antibiotic treatment. This study applied a combination of different imaging approaches of 99mTc-HMPAO-leukocyte scintigraphy: delayed and late planar images, bone marrow imaging and SPECT/CT imaging. All joints were examined with at least two of the approaches and 53 joints with all three approaches. The report was based on the combined results of the approaches used. A chronic PJI was confirmed with a positive microbiological culture. A cured infection was confirmed with either a negative culture or at least 24 months antibiotic-free follow-up with no relapse. In the therapy evaluation group sensitivity was 0.57 and specificity was 0.81. In the suspected chronic infection group sensitivity was 1.00 and specificity 0.91. 99mTc-HMPAO-leukocyte imaging appears to be an accurate method to diagnose or exclude chronic PJI, but cannot be recommended for therapy evaluation of PJI in patients with on-going antibiotic treatment.