Radiological features of experimental staphylococcal septic arthritis by micro computed tomography scan.
BACKGROUND
Permanent joint dysfunction due to bone destruction occurs in up to 50% of patients with septic arthritis. Recently, imaging technologies such as micro computed tomography (μCT) scan have been widely used for preclinical models of autoimmune joint disorders. However, the radiological features of septic arthritis in mice are still largely unknown.


METHODS
NMRI mice were intravenously or intra-articularly inoculated with S. aureus Newman or LS-1 strain. The radiological and clinical signs of septic arthritis were followed for 10 days using μCT. We assessed the correlations between joint radiological changes and clinical signs, histological changes, and serum levels of cytokines.


RESULTS
On days 5-7 after intravenous infection, bone destruction verified by μCT became evident in most of the infected joints. Radiological signs of bone destruction were dependent on the bacterial dose. The site most commonly affected by septic arthritis was the distal femur in knees. The bone destruction detected by μCT was positively correlated with histological changes in both local and hematogenous septic arthritis. The serum levels of IL-6 were significantly correlated with the severity of joint destruction.


CONCLUSIONS
μCT is a sensitive method for monitoring disease progression and determining the severity of bone destruction in a mouse model of septic arthritis. IL-6 may be used as a biomarker for bone destruction in septic arthritis.
Department of Rheumatology and Inflammation Research, Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden.|Department of Pathology and Forensic Medicine, Ribeirao Preto School of Medicine, University of Sao Paulo, Sao Paulo, Brazil.
Farah
F
Fatima
Department of Microbiology and Immunology, Affiliated Hospital of GuiZhou Medical University, Guiyang, P.R. China.
Ying
Y
Fei
Department of Rheumatology and Inflammation Research, Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden.
Abukar
A
Ali
Department of Rheumatology and Inflammation Research, Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden.
Majd
M
Mohammad
Department of Rheumatology and Inflammation Research, Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden.
Malin C
MC
Erlandsson
Department of Rheumatology and Inflammation Research, Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden.
Maria I
MI
Bokarewa
Department of Rheumatology and Inflammation Research, Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden.|Department of Pathology and Forensic Medicine, Ribeirao Preto School of Medicine, University of Sao Paulo, Sao Paulo, Brazil.
Muhammad
M
Nawaz
Department of Rheumatology and Inflammation Research, Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden.
Hadi
H
Valadi
Department of Rheumatology and Inflammation Research, Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden.
Manli
M
Na
Department of Rheumatology and Inflammation Research, Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden.|Department of Rheumatology, Sahlgrenska University Hospital, Göteborg, Sweden.
Tao
http://orcid.org/0000-0001-9039-0628
T
Jin
D000818:Animals; D001170:Arthritis, Infectious / Q000000981:diagnostic imaging* / Q000473:pathology; D004195:Disease Models, Animal; D018450:Disease Progression; D005260:Female; D007596:Joints / Q000000981:diagnostic imaging / Q000382:microbiology / Q000473:pathology; D051379:Mice; D013203:Staphylococcal Infections / Q000000981:diagnostic imaging* / Q000473:pathology; D055114:X-Ray Microtomography