Primary infectious spondylodiscitis in 51 patients over 75 years old: A comparative study

The incidence of infectious spondylodiscitis has been shown to rise with age; however, they had not been extensively investigated in the very elderly.

This retrospective, monocentric study included patients hospitalized in our department of rheumatology for primary infectious spondylodiscitis between 2000 and 2015, and compared over 75-year-olds with younger patients.

Of the 152 patients, 51 (33.6%) were≥75 years old, 59 were 61-74, and 42 were≤60. Patients≥75 years old were more often institutionalized (7.8 vs. 0; P=.02), were less often subject to infection risk factors (27.5 vs. 54.5%; P=.02), but did not differ from the others as regards the frequency of diabetes and cancer. Time to diagnosis was shorter for the under 60-year-olds (23 vs. 30 vs. 30 day for each age group, respectively; P<.05). There were no differences among the age groups in terms of spondylodiscitis localization, frequency of neurological symptoms and fever, frequency or intensity of inflammatory syndrome, imaging use, frequency of microorganism identification, blood culture positivity, or use and efficacy of disco-vertebral biopsy. Microorganism distribution was comparable among the groups, except for Gram-negative bacilli, with Escherichia coli more common in over 75-year-olds (7/8 vs. 4/14; P=.02). Duration of antibiotherapy and hospitalization was comparable across the age groups. Five patients died, all over 75 years old (5/51 vs. 0/101; P=.001).

Age is a risk factor for primary spondylodiscitis, associated with significant mortality in over 75-year-olds (10%). For these elderly patients, spondylodiscitis does not bear any other distinguishing features.