Candida periprosthetic joint infections - risk factors and outcome between albicans and non-albicans strains.

Background: Despite its scarcity, fungal periprosthetic joint infection (PJI) is of great clinical relevance as diagnosis and treatment are highly challenging. Previous analyses focused on the treatment rather than the role of the causative fungal agent on clinical outcome. This is the largest study of its kind to evaluate Candida strain-dependent differences in patients with fungal PJI.

Methods: We retrospectively analyzed 29 patients who underwent surgical intervention due to Candida hip or knee PJI in our department from 2010 to 2018. PJI was defined according to IDSA, recurrent PJI according to modified Delphi consensus criteria. Statistical analysis was performed using t-test, chi-square test with Yates correction, and log rank test.

Results: Besides age and affected joint, no significant differences were found between Candida albicans and non-albicans PJI patients (75.83 versus 64.11 years, p = 0.012; 12 hip versus two knee cases, p = 0.013). Most patients received two- (27.59%) or three-stage exchange surgery (41.38%). There was a statistical trend towards an increase in surgery needed in non-albicans Candida PJI (2.92 versus 2.12; p = 0.103). After initial Candida PJI treatment, functional prosthesis implantation was achieved in 72.41% of all patients. At last follow-up, infection-free survival was at 26.79% in Candida albicans versus 72.00% in non-albicans PJI (p = 0.046).

Conclusions: In this study, we found infection-free survival rates to be significantly decreased in patients with albicans compared to non-albicans Candida PJI. While age and affected joint might play a confounding role, we speculate the causative pathogen to play a decisive role in disease progression.