Serum C-reactive protein, fibrinogen, and interleukin-6 show the best performance among serum markers for diagnosing periprosthetic joint infection (PJI), but they lack sufficient accuracy to confirm or exclude infection reliably. These markers should be re-evaluated in future PJI definitions, as they are not suitable as stand-alone tests. Given their limitations and the superior diagnostic performance of synovial markers, the role of serum markers in PJI diagnosis should be reconsidered.

This work investigates periprosthetic joint infection (PJI) caused by rapidly growing mycobacteria (RGM) following total joint arthroplasty. Eight patients were identified as part of a retrospective review. The isolated RGM species included Mycobacterium abscessus  (three cases), M. fortuitum (three cases), and one case each of M. immunogenum and M. mageritense. We provide novel insights into the successful treatment of PJIs caused by newly identified RGM (M. immunogenum and M. mageritense).

Physicians have difficulties interpreting the isolation of Cutibacterium acnes in the spine tissue. Here we provide the experience of our center about this topic, adding data that can help physicians in their choices. Our results show that some clinical, radiological, and microbiological features can help distinguish patients to treat or not to treat. Moreover, treatment with parenteral beta-lactams appears to be effective, but targeted oral therapy could be a valid alternative.

This retrospective case-matched study evaluated males and females with staphylococcal PJI (periprosthetic joint infection) treated with two-stage exchange arthroplasty. We matched 156 males and females for age, type of staphylococcal infection, and joint involved. We compared clinical parameters related to presentation, treatment, and outcome. We did not find a statistically significant difference in outcome between males and females treated with the same surgical approach at our institution.

We present the first published case of bilateral extensor tenosynovitis caused by Coxiella burnetii. C. burnetii should be considered in patients with inflammatory osteoarticular disease, including tenosynovitis, when conventional cultures are negative especially in elderly, male, or immunocompromised patients with exposure to animals.