Histopathologic Reaction Patterns in Decorative Tattoos

In recent years, the practice of decorative tattooing has seen rising popularity and increased social acceptance. As newer tattoo inks are developed and utilized, it is expected that the rate of reactions will rise. Thus, dermatologists are more likely to encounter tattoo-related complications. An understanding of the most common histopathologic reaction patterns ideally will result in increased clinical detection of situations requiring additional evaluation, whether it is for an underlying infection, systemic involvement of disease, or to rule out a cutaneous malignancy. This review will describe both the clinical and histopathologic features of pathologic reactions to decorative tattoos. The main histopathologic reactions are divided into six distinct categories: allergic hypersensitivity, granulomatous, interface, pseudolymphomatous, oncologic and infectious.