POS1159 THE ROLE OF URINARY TRACT INFECTIONS AS A SOURCE OF OSTEOARTICULAR INFECTIONS IN A RHEUMATOLOGY DEPARTMENT DURING THE 2010-2020 PERIOD: A RETROSPECTIVE STUDY
Authors: C. Bendahmane, M. Chammakhi, F. Kemiche, I. Cerf-Payrastre, E. Pertuiset
Journal: Annals of the Rheumatic Diseases (2021)

Background: There are several sources of infection in the pathogenesis of osteoarticular infections (OAI). Urinary tract infections (UTI) have rarely been involved whereas skin infection and Staphy lococcus aureus represent the classic pair. Objectives: To describe the role of UTI as the source of infection in OAI including septic arthritis (SA) on native joints and infectious spondylodiscitis (SPDI). To compare characteristics of these cases with those of others source and those without any known source. Methods: Medical records of patients aged 18 years old or above who were diagnosed with a non-tuberculous OAI in the department of rheumatology of our hospital during the 2010-2020 period were selected and retrospectively reviewed. The following cases were excluded: SA on prosthetic joint, OIA on surgical material, osteomyelitis, post-operative OAI, SA after joint injection, brucellosis, Lyme disease. Only proven cases where included on the basis of an isolated pathologic organism at the site of OAI infection and/or in the blood (with typical clinical, biological and imaging features). Usually the OAI was considered of urinary source if the same microorganism grew in urine and the OA/blood sample. Cases with probable urinary source were also included on the basis of the type of microorganism and a history of UTI and/or urologic surgery and/or recent antibiotic therapy. Results: 95 consecutive cases of proven OAI were included. There were 17 cases (18%) of urinary origin. In 12 cases the same micro-organism grew in urine and OA/blood culture: 5 methicillin sensitive Staphylococcus aureus , 2 Streptococcus Gallolyticus (associated with E. Coli in one case), 1 Escherichia Coli , 1 Klebsiella pneumoniae , 1 Enterococcus faecalis , 1 aerococcus urinae , 1 candida glabrata. Five patients had a probable urine source. In one patient with SPDI and an history of recurrent UTI, blood culture grew E. Coli whereas urine culture grew Enterococcus faecalis . In 4 cases, urine was sterile but a sample (OA in 3, blood in 1) was positive for E. Coli (n=2) or Pseudomonas aeruginosa (n=2). The type of OAI was: SPDI in 10 cases, peripheral SA in 4 cases, both of them in one case and pubic symphysitis in 2 cases. Blood culture was positive in 10 cases and OA sample in 9 cases. Demographics characteristics were: male 59%; age 68.7±11 years. Risk factors were: diabetes 29%; cancer treated with cytotoxic chemotherapy 2 cases; inflammatory disease 2 cases; urological disease and/or recurrent UTI in 59%; immunodeficiency 1 case. Duration of symptoms was 47.1 +/- 50.7 days. Urinary symptoms where present in 29% of patients and fever in 47%. There was no case of infectious endocarditis. Surgical intervention was realized in only one patient. No patient has been admitted in intensive care unit and no patient died. Length of hospitalization was 28±8.5 days. Duration of antibiotic therapy was 13.6±9 weeks. One patient with pubic symphysitis was not cured. The comparison between the group of OAI with urinary source (n=17) and the groups with another primary source of infection (n=52) or no known source of infection (n=26) shows in the first one: a higher prevalence of SPDI (59% vs 34% and 19% respectively), an older age (68.7 years vs 61.9 and 59.7 respectively), a higher prevalence of diabetes or cancer, a longer duration of symptoms (47.1+/-50.7 days vs 21.9+/-29.6 and 22.5+/-25.4 respectively) and a lower mean value of CRP (156+/-135 mg/l vs 182+/-124 and 180+/-140 respectively). A UTI was detected in 76% of OAI of urinary source but also in 13% of other cases (including E. Coli 5 cases). Conclusion: In the years 2010-2020, UTI was responsible for 18% of non-tuberculous OAI as we defined them in this study. A UTI does not demonstrate the responsibility of the microorganism isolated. Thoracolumbar SPDI is the main type. This relatively high frequency has not been reported before and is probably the consequence of the increasing population of aged patients with risk factors and urologic diseases. Clinicians have to be aware of it and prevention is required. Disclosure of Interests: None declared.