Persistent, Intermitent Delayed Swelling PIDS intermitent swelling: late adverse reaction to Hyaluronic Acid fillers

The use of hyaluronic acid fillers (HA) for esthetic corrections has exponentially grown in recent years. Skin ultrasound (US) is an effective method to identify the filler and its complications. A particular type of adverse effect, characterized by late, persistent edema of an intermittent nature, has been lately observed. Objective: To describe a delayed complication due to easy HA fillers, named by the authors as Persistent, Intermitent Delayed Swelling (PIDS). Methods: From October 2016 to July 2017, US examinations performed at Cavallieri Clinic were selected and referred for evaluation of post-filler complications. Questionnaires were sent to requesting physicians for clinical data collection. Results: Of 108 exams, 33 cases of local subcutaneous edema associated with the presence of HA fillers were identified. Episodes of edema were referred to as recurrent, in the previously affected area, or at another injection site. Conclusion: The authors propose a specific nomenclature: PIDS to refer to this late adverse reaction to HA fillers, which includes delayed and intermittent local swelling, triggered by specific conditions, that persists for as long the HA remains in the subcutaneous tissue