Adverse reactions to injectable soft tissue fillers: memorable cases and their clinico-pathological overview

Filler injection is a minimally invasive procedure widely used for soft tissue augmentation. Although the safety profile is favorable, adverse events can occur, especially after illegal filler injection.

The authors present memorable cases of filler complications and review their clinico-pathological features and treatment strategies.

This is a retrospective, single-center case series. The authors identified eight patients with significant complications following filler injection. A medical record review was performed for clinical history, histopathological studies, and treatment.

Six female and two male subjects presented with significant filler complications. The time interval between filler injection and the development of a complication varied greatly among cases (immediately afterwards to 14 years following filler injection). Four of the patients received illegal filler injection where the injected material was either unknown (25%) or was told as paraffin (12.5%) or Vaseline(®) (12.5%). Hyaluronic acid fillers were used in two patients (25%) and the rest were injected with porcine atelocollagen (12.5%) and polyacrylamide hydrogel (12.5%). The complications were classified as an allergic reaction (25%), filler material migration (12.5%), injection necrosis + embolism (25%), and foreign body granuloma (37.5%), based on their clinico-pathological features and were treated accordingly.

Adverse effects are not uncommon following filler injection. Physicians should be aware of the potential side effects, recognize their presentations, and understand how to manage them.