Neutrophilic dermatoses.

Neutrophils may infiltrate all layers of the skin and consequently may cause different disorders, each with its own characteristic clinical and laboratory findings. We discuss how these disorders present and how they are diagnosed and treated. In addition, important associations with internal diseases are discussed to assist clinicians in evaluating for a concurrent illness. Because treatment of these disorders may often require systemic therapy, the potential short-term and long-term effects of commonly used medications are discussed. Finally, treatment of recalcitrant diseases, mostly by use of therapies published in the form of small case series or reports, is also included to guide clinicians in dealing with the more challenging cases.