Localized infection and leg ulcer after platelet‐rich plasma injection

Adverse events related to platelet-rich plasma therapy and future issues to be resolved

Platelet-rich plasma (PRP) is the portion of plasma with a platelet concentration above baseline that is recovered through centrifugation of autologous blood. PRP therapy is currently used for wound healing and pain relief in diverse medical fields. Although there have been recent reports of adverse events (AEs) possibly related to PRP treatment, the safety profile of PRP treatment remains unclear. Therefore, this review discusses the risks inherent in PRP therapy and the current issues by surveying reports on AEs associated with PRP treatment within different fields. PubMed was searched for research articles referring to AEs associated with PRP therapy from inception to January 2024. Literature survey revealed that PRP therapy may involve several AEs, including postoperative infections, blindness, inflammation, allergic reactions, and nodule development. The most commonly reported AE was postoperative infections. Since PRP therapy generally proceeds in the process of blood collection, manufacturing, and administration to patients, it is conjectured that PRP may have been contaminated with microorganisms at some point in this series of processes, leading to bacterial infection. Additionally, because PRP cannot be sterilized like pharmaceuticals, it is important to prevent microbial contamination during each PRP treatment process. However, the specific process that involves the risk of microbial contamination remains unclear. To take measures to prevent microbial contamination of PRP, it may be necessary to elucidate the risk factors for microbial contamination during PRP treatment. It may be important to elucidate the effectiveness and risks of PRP therapy as well as to establish a follow-up system after PRP treatment. Currently, most reports of AEs related to PRP therapy are case reports; therefore, the accumulation of high-quality evidence and detailed verification are necessary to determine the causal relationship between PRP therapy and each AE.

Current status of platelet-rich plasma therapy under the act on the safety of regenerative medicine in Japan

In Japan, a legal framework has been established for the safe and effective application of regenerative medicine. After eight years of the Act on the Safety of Regenerative Medicine (RM Act), discussions have been underway in the Ministry of Health, Labor and Welfare of Japan to revise the law owing to numerous novel technologies and inappropriate case reports not anticipated when the law was enacted. Therefore, in this review article, we have reviewed the regenerative medicine provision plans and the contribution of platelet-rich plasma (PRP) therapy, a regenerative medicine technique widely used in Japan post RM Act implementation, to these plans. As of January 2022, 97.2% of the regenerative medicine provided under the RM Act had been for private practice, and most of them were Class Ⅲ regenerative medicine. Notably, PRP was the most used processed cell under the RM Act. PRP therapy accounted for approximately 66% of the regenerative medicine provision plans in clinical research or private practice and was the most provided regenerative medicine technology in Japan. PRP therapy was primarily used in dentistry to regenerate periodontal tissue (approximately 50%), followed by orthopedics, where it is used to treat osteoarthritis. We suggest that further discussion is essential to determine the factors that should be addressed by the RM act to evaluate the efficacy and safety of PRP therapy.