Eric T. Ricchetti
CHICAGO — At the American Shoulder and Elbow Surgeons Open Symposium, Eric T. Ricchetti, MD, presented recommended standardized protocols for obtaining intraoperative tissue specimens, tissue culture technique and new diagnostic criteria for infection of the shoulder.
Although standard diagnostic tests have been found to be effective in the identification of infection in the hip and knee, Ricchetti noted data on the shoulder are limited.
“The work group is currently recommending use of the current thresholds in the hip and knee literature, but when we use these thresholds in the shoulder, there is a lower sensitivity,” Ricchetti said. “However, these tests will have high specificity.”
He added culture sampling and analysis has no standardized protocol for the shoulder, but that specimen type, culture technique and culture length are important when it comes to Propionibacterium acnes recovery. One consensus made around culture analysis was to perform culture tissue samples with aerobic and anaerobic conditions with a 14-day culture hold, according to Ricchetti.
“For intraoperative culture sampling protocol, the following were recommended: obtain specimen in any case where there is high concern for infection; not holding preoperative antibiotics; taking five deep tissue specimens from different areas of the shoulder after revision surgery; and using fresh instruments for each specimen,” Ricchetti said.
The work group then created consensus diagnosis criteria for periprosthetic joint infection of the shoulder using a scoring system for likelihood of infection in cases without a definite infection. Under the scoring system, Ricchetti noted patients would be identified as having a probable infection, possible infection or unlikely to be infected based on total scores and whether a patient has a virulent or non-virulent organism.
“[Post-scoring weight] includes positive culture results, and there are different scores for either non-virulent or virulent cultures; humeral loosening is significant and, again, with the standard diagnostic test, we used the hip and knee thresholds that currently exist,” Ricchetti said. – by Casey Tingle
Ricchetti ET. Best way to evaluate infection, serology and culture? Presented at: American Shoulder and Elbow Surgeons Open Symposium; Oct. 11, 2018; Chicago.
Disclosure: Ricchetti reports he is a board or committee member of the American Shoulder and Elbow Surgeons and is a paid consultant and paid presenter or speaker for DJO.