It is important to know the spectrum of the microbial aetiology of prosthetic joint infections (PJIs) to guide empiric treatment and establish antimicrobial prophylaxis in joint replacements. There are no available data based on large contemporary patient cohorts. We sought to characterize the causative pathogens of PJIs and to evaluate trends in the microbial aetiology. We hypothesized that the frequency of antimicrobial-resistant organisms in PJIs has increased in the recent years. We performed a cohort study in 19 hospitals in Spain, from 2003 to 2012. For each 2-year period (2003-2004 to 2011-2012), the incidence of microorganisms causing PJIs and multidrug-resistant bacteria was assessed. Temporal trends over the study period were evaluated. We included 2524 consecutive adult patients with a diagnosis of PJI. A microbiological diagnosis was obtained for 2288 cases (90.6%). Staphylococci were the most common cause of infection (1492, 65.2%). However, a statistically significant rising linear trend was observed for the proportion of infections caused by Gram-negative bacilli, mainly due to the increase in the last 2-year period (25% in 2003-2004, 33.3% in 2011-2012; p 0.024 for trend). No particular species contributed disproportionally to this overall increase. The percentage of multidrug-resistant bacteria PJIs increased from 9.3% in 2003-2004 to 15.8% in 2011-2012 (p 0.008), mainly because of the significant rise in multidrug-resistant Gram-negative bacilli (from 5.3% in 2003-2004 to 8.2% in 2011-2012; p 0.032). The observed trends have important implications for the management of PJIs and prophylaxis in joint replacements.

No abstract

No abstract

As osteomyelitis (OM) induces the synthesis of inflammatory cytokines and IL-1 mediates bone resorption by osteoclasts we determined if there is an association between certain common polymorphisms of the genes encoding proinflammatory cytokines (IL-1 alpha and beta, IL-6, TNF-alpha) and OM in adults. The IL-1 alpha (-889) TT genotype was significantly more frequent among 52 OM patients than in 109 healthy controls (13/52, [25.0%] vs. 9/109, [8.3%], P = 0.0081, chi(2) = 7.01, OR = 3.7, 95% CI, 1.35-10.34). Patients who were homozygous for the T allele were younger than the rest of the OM patients (mean age 35.7 +/- 11.5 vs. 58.1 +/- 18.6 years, P = 0.001). IL-1 beta TT (+3953) polymorphism was also more frequent in OM patients (P = 0.014, chi(2) = 5.12, OR = 5.1, 95% CI, 1.21-52.14), but IL-1 beta is in linkage disequilibrium with the IL-1 alpha *T (P < 0.001). Route of infection, chronicity of the infection, type of microorganism isolated, and frequency of relapses were similar in patients with and without the IL-1 alpha TT genotype. There were no associations between OM and polymorphisms of other cytokines genes. IL-1 alpha serum levels were significantly increased in all the OM patients independently of their IL-1 genotype compared to the controls (P = 0.021). Although IL-1 alpha serum levels were not significantly higher in patients with the IL-1 alpha (-889) polymorphism, this does not exclude a difference in production of IL-1 alpha by osteoclasts or other inflammatory cells at the site of infection.

Most cases of endocarditis in patients with AAPG occur late after initial surgery. Mortality rate of patients with AAPG endocarditis who undergo surgery is acceptable. NYHA Class IV before surgery is associated with an increased postoperative mortality.