Abstract
Aim
The risk for developing a periprosthetic joint infection (PJI) as a consequence of bacteremia is not clear, except for Staphylococcus aureus bacteremia, and patient-related risk factors for it are not known. The aim of this study was to investigate the risk for developing a PJI during any bacteremia and to find out possible risk factors leading to it.
Method
All patients with a primary knee or hip joint replacement performed between September 2002 and December 2013 in a tertiary care hospital (n=14 378) were retrospectively followed up until December 2014. The mean follow-up time was 6.0 years (range 0–12 years). Positive blood culture results of the patients during the study period were obtained. PJIs during the study period were identified from several data sources. PJIs as a consequence of bacteremia were recorded and confirmed from patient records. Primary PJIs resulting in bacteremia were excluded. Binary logistic regression with univariate analysis was used to study potential risk factors for PJI among those with bacteremia.
Results
Of the study patients, 542 (3.8%) had at least one episode of bacteremia. In total, there were 643 episodes of bacteremia. The incidence rate of bacteremia was 7.4 per 1 000 person-years. Seven percent (47/643) of the bacteremias resulted in a PJI. The risk for PJI was highest for bacteremias caused by Staphylococcus aureus (21% of bacteremias led to a PJI) and beta-hemolytic streptococci (21%), but it was low for gram-negative bacteria (1.3%). Patients with two or more bacteremias during the study period had an increased risk for developing a PJI (OR 2.29, 95%CI 1.17–4.50). Bacteremias occurring within a year from previous surgery were associated with the highest risk for developing a PJI. Chronic comorbidities, obesity, gender, joint location, indication for surgery or use of antibiotic-loaded cement did not affect the risk for PJI during bacteremia.
Conclusions
The pathogen causing the bacteremia, number of bacteremias and the timing of bacteremia with respect to previous surgery affect the risk for developing a PJI as a consequence of bacteremia. Thus the type of pathogen, previous history of infections and the timing of bacteremia should be taken into account when evaluating the risk for PJI on a patient with bacteremia. On the other hand, significant patient-related risk factors for PJI during bacteremia could not be identified.
