Foreign Body Reaction to Hyaluronic Acid (Restylane®): An Adverse Outcome of Lip Augmentation

Abstract

Non-animal source hyaluronic acid (Restylane®) is a relatively new redefining dermal filler that is being employed with increasing frequency in the fields of dermatology and cosmetic/facial plastic surgery. We report a case of a 74-year-old woman who presented with a firm submucosal nodule of the lower lip, which clinically was thought to represent a benign neoplasm. An excisional biopsy revealed the presence of multiple cyst-like vacuolated areas surrounded by granulomatous tissue composed predominantly of histiocytes and foamy macrophages, consistent with a foreign body reaction. Subsequent to the pathology findings, the patient acknowledged that she had received injections of Restylane® to the lips approximately 6 months before discovering the nodule. She had not mentioned this to her dentist or oral and maxillofacial surgeon to whom she had been referred because she believed that these two events were not related. Although hyaluronic acid-based dermal fillers reportedly have a low incidence of long term side effects, clinicians should be aware of the possible development of foreign body reactions to these injectable agents.