Rheumatoid neutrophilic dermatitis (RND) is a recently recognized, rare cutaneous manifestation of rheumatoid arthritis. It occurs in patients with severe rheumatoid arthritis and is typically asymptomatic. Rheumatoid neutrophilic dermatitis was originally described by Ackerman in 1978. Since that time, 8 patients with this disease have been described in the literature.
We report 2 cases of RND. Findings of skin biopsy specimens from both patients revealed characteristic signs of dermal leukocytosis and leukocytoclasia without vasculitis. The pathogenesis of the neutrophilic infiltrate is unclear. Processes that may play a role in the pathogenesis of RND include immune complex activations, cell adhesion and migration, and cytokine release.
Rheumatoid neutrophilic dermatitis falls into the spectrum of neutrophilic vascular reactions described by Jorizzo and Daniels. Although early reports suggest that prominent leukocytoclasia is not a feature of RND, our findings confirm the observations of Lowe et al that leukocytoclasia can be seen in RND and may be striking. It is important for dermatologists to be aware of this rare manifestation of rheumatoid arthritis.