Study: Revision shoulder arthroplasty patients have lower sensitivity to Propionibacterium acnes

Patients who undergo revision total shoulder arthroplasty show lower sensitivity to Propionibacterium acnes infection as compared to other infections, according to results of a recently published study. 

“Using current histopathology grading systems, frozen sections were specific but showed low sensitivity with respect to the Propionibacterium acnesinfection,” said Michael J. Grosso, BS.

The researchers retrospectively studied 45 patients who underwent revision total shoulder arthroplasty. Overall, 15 patients were in the non-infection group, 18 patients in the P. acnes infection group and 12 patients the other infection group. They performed preoperative testing and collected intraoperative tissue culture and frozen section histology.

Sensitivity was lower for the P. acnes infection group (50%) compared with the other infection group (67%). Frozen section specificity was 100%. An optimized threshold was found at a total of 10 polymorphonuclear leukocytes in five high-power (400×) fields. At this threshold, sensitivity of the frozen section for P. acnes increased to 72%, however, specificity was not altered.

“Because this was a retrospective study, we recommend caution in using this new threshold to decide one-stage or two-stage revision with no other supporting criteria. A prospective study with a larger number of both infected and non-infected cases is needed,” the authors concluded.

Disclosures: No authors received payments or services from a third party for this work. One or more of the authors, or his or her institution, has had a financial relationship, in the 36 months prior to submission of this work, with a biomedical entity that could be perceived to have the potential to influence this work. No author has had any other relationships or has engaged in activities that could be perceived to have influenced this work.