AB0908 Biological and radiographic findings impact on germ identification during septic arthritis
Authors: H Sahli, M Sahli, R Tekaya, R Khalfallah, O Saidane, I Mahmoud, L Abdelmoula
Journal: Annals of the Rheumatic Diseases (2017)

<h3>Background</h3> Septic arthritis may cause damage and inflammation in short period of time. The germ determination must be the first objective to allow targeted treatment. Bacteriological tests remain negative in 7–35% of cases of septic arthritis. <h3>Objectives</h3> The aim of this study was to determine the impact of biological and radiographic findings on germ identification during septic arthritis. <h3>Methods</h3> This a retrospective study which included medical records of patients treated for septic arthritis during the seventeen past years. Epidemiologic, clinical, biologic, bacteriologic and therapeutic data were recorded and analysed. We made a comparison between patients who had a germ identified (Group 1) with whom who hadn9t (Group 2). <h3>Results</h3> Fifty nine patients with septic arthritis were included in this study. The mean age of the patients was 54.6±19 years and a sex ratio (F/M) of 0.9. Causative agents were isolated in 27 patients (45.7%). Biological data showed leukocytosis in 25 (42.4%) patients. Mean leukocyte count was 10673±5003. Leukopenia was noted in 1 case. One patient had neutropenia. Lymphopenia was observed in 4 patients (6.7%). Two patients had hyperlymphocytosis. Anemia, mainly of the inflammatory type, was noted in 47 cases (79.66%). The mean Creactive protein (CRP) was 150.6±106, and the mean erythrocyte sedimentation rate (ESR) was 104.9. Twenty three patients (38.9%) had other perturbations of the biological balance: cholestasis (n=1), cytolysis (n=4) and renal perturbation (n=15). Radiological signs suggestive of septic arthritis were observed in 40 cases (67.8%): articular pinching (28.8%), geodes and erosions (14%), total destruction of the joint (0.67%) or thickening f the soft parts at the beginning (11.86%). Ultrasound exam, performed in 22 cases, showed articular effusion (n=15), synovial thickening (n=8), a soft tissue collection (n=3), and periarticular erosion (n=2). CT, performed in 6 patients, was normal in one case. The abnormalities noted were: collection of soft parts (n=2), joint effusion (n=2), bone demineralization (n=1), bone erosion (n=1) and osteochondritis (n=1). MRI, performed in 2 patients, was pathological in both cases and showed synovitis and cortical erosion with medullary edema. The comparison of the 2 groups according to germ identification showed that biological inflammatory syndrome was more frequent in group 2 (100% versus 96.8%) but without a statistically significant difference (p=0.346). Mean value of CRP and ESR were comparable in the two groups (p=0.65 and 0.19). The mean value of hemoglobin was comparable in the two groups (10.87 versus 10.54 g/dl) (p=0.566). It was similar about the blood count. Abnormalities of standard x-rays were similar in both groups (70.4% in group 1 versus 65.5% in group 2) (p=0.784). The most frequent radiological abnormality in the two groups was articular pinching (40.7% in group 1 and 46.8% in group 2). <h3>Conclusions</h3> In our study, the biological and radiological data had not shown any impact on the identification of the germ. <h3>Disclosure of Interest</h3> None declared