The US Food and Drug Administration (FDA) announced on Thursday that it has approved marketing of the Synovasure Lateral Flow Test Kit to aid in the detection of periprosthetic joint infection in the synovial (lubricant) fluid of patients being evaluated for revision surgery, which is surgery performed to replace or compensate for a failed implant.

The marketing authorisation for the Synovasure Lateral Flow Test Kit was awarded to CD Diagnostics Inc.

According to the agency, Synovasure Lateral Flow Test Kit detects proteins called human alpha defensins in the synovial fluid of patients with a total joint replacement in approximately ten minutes. Alpha defensins are antimicrobial proteins released by activated neutrophils (white blood cells) in response to infection.

The product is used to determine only the presence of infection in synovial fluid. The test results are intended to be used in conjunction with other clinical and diagnostic findings to aid in a patient's diagnosis of prosthetic joint infection.

Through the FDA's de novo premarket review pathway, the agency reviewed data from the company's clinical study that analysed 305 prospective synovial fluid samples collected from individuals with a total knee or hip joint replacement who were being evaluated for revision surgery. The study showed that 89.5% of subjects with an infection diagnosis based on standard of care criteria were identified as positive for alpha defensin by the Synovasure Lateral Flow Test Kit.