Epidemiologic and microbiologic aspects of 33 osteitis and anaerobes.

We analyzed 33 cases of osteitis or infectious osteoarthritis in which biopsies had isolated one or several anaerobic bacteria. The diagnosis of anaerobic infection was definitive if the anaerobes had been isolated from reliable perioperative biopsies or at least two unreliable biopsies (fistula, needle biopsy), and on the condition that the different results were correlated. One hundred and eighteen bacteria were isolated from the 33 patients, of which 81 were purely anaerobic bacteria, i.e., 2.39 bacteri per patient (including 20 Peptostreptococus, 16 Prevotella, 12 Bacteroides, of which six were in the fragilis group, ten Propionibacterium acnes and eight Fusobacterium nucleatum). Twenty-four cases of osteitis were caused by mixed infections (73%), and nine (27%) were exclusively due to anaerobes, of which seven were monomicrobic. We analyzed the infections and the distribution of bacterial etiologies according to the localization, method of contamination and the risk factors. (C) 2000 Editions scientifiques et medicales Elsevier SAS.